Lochinvar Knight 151, Knight 286, Knight 211, Knight OKN151, Knight OKN211 Operation Manual

OKB-I-O Rev C

Outdoor Knight Boiler

Installation & Operation

Manual

Models: 151 - 286

 WARNING

Save this manual for future reference.

This manual must only be used by
a qualified heating installer / service
technician. Read all instructions,
including this manual and the
Outdoor Knight Boiler Service
Manual, before installing. Perform
steps in the order given. Failure
to comply could result in severe
personal injury, death, or substantial
property damage.

Contents

HAZARD DEFINITIONS .................................................... 2

PLEASE READ BEFORE PROCEEDING ........................ 3

THE OUTDOOR KNIGHT BOILER -- HOW IT WORKS 4-6

RATINGS ........................................................................... 7

1. DETERMINE BOILER LOCATION

Provide Clearances ............................................................ 9

Corrosive Contaminants and Sources ............................... 9

2. PREPARE BOILER

Remove Boiler from Wood Pallet ..................................... 10

Gas Conversions ......................................................... 10-11

Leveling the Boiler ...................................................... 11

3. HYDRONIC PIPING

System Water Piping Methods ......................................... 12

Low Water Cutoff Device ................................................. 12

Chilled Water System ....................................................... 12

Freeze Protection ............................................................. 12

General Piping Information .............................................. 12

Relief Valve / T & P Installation ....................................... 13

Near Boiler Piping Components .................................. 13-14

Near Boiler Piping Connections ....................................... 14

Circulator Sizing ............................................................... 14

Variable Speed Pump Option .......................................... 16

4. GAS CONNECTIONS

Connecting Gas Supply Piping ................................... 24-25

Natural Gas ...................................................................... 25

Pipe Sizing for Natural Gas ........................................ 25

Natural Gas Supply Pressure Requirements ............. 25

Propane Gas .................................................................... 25

Pipe Sizing for Propane Gas ...................................... 25

Propane Supply Pressure Requirements ................... 25

Check Inlet Gas Supply ................................................... 26

Gas Pressure ................................................................... 27

Gas Valve Replacement .................................................. 27

5. FIELD WIRING

Line Voltage Connections ................................................ 28

Low Voltage Connections ................................................ 28

Wiring of the Cascade ...................................................... 30

6. CONDENSATE DISPOSAL

Condensate Drain ............................................................ 32

7. STARTUP ............................................................... 33-38

8. OPERATING INFORMATION

General ............................................................................. 39

Cascade ........................................................................... 42

Sequence of Operation ............................................... 43-44

Outdoor Knight Boiler Control Module ............................. 45

Status Display Screens ............................................... 46-48

9. MAINTENANCE

Maintenance and Annual Startup ................................ 49-53

10. DIAGRAMS

Ladder Diagram ............................................................... 54

Wiring Diagram................................................................. 55

Revision Notes .................................................. Back Cover

Hazard definitions

The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels or
to important information concerning the life of the product.

 DANGER

 WARNING

 CAUTION

CAUTION

NOTICE

2

DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious
injury.

WARNING indicates a potentially hazardous situation which, if not avoided, could result in death or serious
injury.

CAUTION indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate
injury.

CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not
avoided, may result in property damage.

NOTICE indicates special instructions on installation, operation, or maintenance that are important but not
related to personal injury or property damage.

Outdoor Knight Boiler Installation & Operation Manual

Please read before proceeding

 WARNING

NOTICE

 WARNING

 WARNING

Installer – Read all instructions, including
this manual and the Outdoor Knight
Boiler Service Manual, before installing.
Perform steps in the order given.

User – This manual is for use only
by a qualified heating installer/
service technician. Refer to the User’s
Information Manual for your reference.

Have this boiler serviced/inspected by
a qualified service technician, at least
annually.

Failure to comply with the above could
result in severe personal injury, death or
substantial property damage.

When calling or writing about the boiler
– Please have the boiler model and serial
number from the boiler rating plate.

Consider piping and installation when
determining boiler location.

Any claims for damage or shortage in
shipment must be filed immediately
against the transportation company by
the consignee.

Factory warranty (shipped with unit) does
not apply to units improperly installed or
improperly operated.

Failure to adhere to the guidelines on this
page can result in severe personal injury,
death, or substantial property damage.

If the information in this manual is not
followed exactly, a fire or explosion may
result causing property damage, personal
injury or loss of life.

This appliance MUST NOT be installed in
any location where gasoline or flammable
vapors are likely to be present.

WHAT TO DO IF YOU SMELL GAS

• Do not try to light any appliance.

• Do not touch any electric switch; do
not use any phone in your building.

• Immediately call your gas supplier
from a near by phone. Follow the
gas supplier’s instructions.

• If you cannot reach your gas supplier,
call the fire department.

• Installation and service must be
performed by a qualified installer,
service agency, or the gas supplier.

When servicing boiler –

• To avoid electric shock, disconnect electrical supply
before performing maintenance.

• To avoid severe burns, allow boiler to cool before
performing maintenance.

Boiler operation –

• Do not block flow of combustion or ventilation air to
the boiler.

• Should overheating occur or gas supply fail to shut off,
do not turn off or disconnect electrical supply to
circulator. Instead, shut off the gas supply at a location
external to the appliance.

• Do not use this boiler if any part has been under water.
The possible damage to a flooded appliance can be
extensive and present numerous safety hazards. Any
appliance that has been under water must be replaced.

Boiler water –

• Thoroughly flush the system (without boiler
connected) to remove sediment. The high-efficiency
heat exchanger can be damaged by build-up or
corrosion due to sediment.

• Continual fresh make-up water will reduce boiler life.
Mineral buildup in the heat exchanger reduces heat
transfer, overheats the stainless steel heat exchanger,
and causes failure. Addition of oxygen carried in by
makeup water can cause internal corrosion in system
components. Leaks in boiler or piping must be repaired
at once to prevent makeup water.

 CAUTION

 CAUTION

Do not use petroleum-based cleaning or
sealing compounds in the boiler system.
Gaskets and seals in the system may be
damaged. This can result in substantial
property damage.

Do not use “homemade cures” or “boiler
patent medicines”. Serious damage to
the boiler, personnel, and/or property
may result.

Freeze protection fluids –

• NEVER use automotive antifreeze. Use only inhibited
propylene glycol solutions, which are specifically
formulated for hydronic systems. Ethylene glycol is
toxic and can attack gaskets and seals used in hydronic
systems.

3

The Outdoor Knight Boiler - How it works...

1. Stainless steel heat exchanger

Allows system water to flow through specially designed
coils for maximum heat transfer, while providing
protection against flue gas corrosion. The coils are
encased in a jacket that contains the combustion process.

2. Combustion chamber access cover

Allows access to the combustion side of the heat
exchanger coils.

3. Blower

The blower pulls in air and gas through the venturi (item

5). Air and gas mix inside the blower and are pushed into the
burner, where they burn inside the combustion chamber.

4. Gas valve

The gas valve senses the negative pressure created by the
blower, allowing gas to flow only if the gas valve is
powered and combustion air is flowing.

5. Venturi

The venturi controls air and gas flow into the burner.

6. Flue gas sensor (limit rated)

This sensor monitors the flue gas exit temperature. The control
module will modulate and shut down the boiler if flue gas
temperature gets too hot. This protects the flue pipe from
overheating.

7. Boiler outlet temperature sensor (housed with the
high limit sensor)

This sensor monitors boiler outlet water temperature (system
supply). If selected as the controlling sensor, the control
module adjusts boiler firing rate so the outlet temperature is
correct.

8. Boiler inlet temperature sensor

This sensor monitors return water temperature (system
return). If selected as the controlling sensor, the control
module adjusts the boiler firing rate so the inlet temperature is
correct.

9. Temperature and pressure gauge (field installed, not
shown)

Monitors the outlet temperature of the boiler as well as the
system water pressure.

10. Electronic LCD display

The electronic display consists of 4 buttons, a navigation dial
and a multiple line liquid crystal display.

11. Flue pipe adapter

Allows for the connection of the vent system to the
boiler.

12. Burner (not shown)

Made with metal fiber and stainless steel construction,
the burner uses pre-mixed air and gas and provides a
wide range of firing rates.

13. Water outlet (system supply)

NPT water connection that supplies hot water to the
system, either 1" or 1-1/4", depending on the
model.

14. Water inlet (system return)

NPT water connection that returns water from the
system to the heat exchanger, either 1" or 1-1/4",
depending on the model.

15. Gas connection pipe

Threaded pipe connection, either 1/2" or 3/4",
depending on the model. This pipe should be connected
to the incoming gas supply for the purpose of delivering
gas to the boiler.

16. SMART SYSTEM Control Module

The SMART SYSTEM Control responds to internal and
external signals and controls the blower, gas valve, and pumps
to meet the heating demand.

4

Outdoor Knight Boiler Installation & Operation Manual

17. Manual air vent

Designed to remove trapped air from the heat exchanger
coils.

18. High voltage junction box

The junction box contains the connection points for the line
voltage power and all pumps.

19. Boiler drain port

Location from which the heat exchanger can be drained.

20. Low voltage connection board

The connection board is used to connect external low voltage
devices.

21. Low voltage wiring connections

Conduit connection points for the low voltage
connection board.

22. Condensate drain connection

Connects the condensate drain line to a 1/2" PVC union.

23. Access cover - top front

Provides protection of the control panel / display from outside
elements.

24. Access cover - bottom front

Provides access to the burner.

25. Ignition electrode

Provides direct spark for igniting the burner.

26. Flame inspection window

The quartz glass window provides a view of the burner
surface and flame.

27. Relief valve

Protects the heat exchanger from an over pressure condition.
The relief valve provided with the unit is set at 30 psi.

28. Flame sensor

Used by the control module to detect the presence of burner
flame.

29. Line voltage wiring connections

Conduit connection points for the high voltage junction box.

30. Top access cover

Provides access to the internal components.

31. Power switch

Turns 120 VAC ON/OFF to the boiler.

32. Leveling legs

Used to allow the heat exchanger to be leveled. This is needed
for the proper draining of the condensate from the combustion
chamber.

33. Air pressure switch

The air pressure switch detects blocked inlet conditions.

34. Transformer

The transformer provides 24V power to the integrated control.

35. High limit sensor (housed with the outlet
temperature sensor)

Device that monitors the outlet water temperature. If the
temperature exceeds its setting, the integrated control will
break the control circuit, shutting the boiler down.

36. Gas shutoff switch

An electrical switch designed to cut power to the gas valve to
prevent releasing any gas.

37. Over-temp switch (Model 286 Only) (located underneath
access cover)

An electrical switch designed to shut down boiler operation in
the event the outer back of the heat exchanger, directly above the
flue connection exceeds 604°F (318°C). This is a one time
switch and could warrant a heat exchanger replacement. Check
the integrity of the rear refractory at the back of the upper coil if
the switch opens.

38. Air cover

Covers the over-temp switch and the flue collar with flue sensor.

39. Flue pipe assembly

Factory supplied components for a complete venting system.

Outdoor Knight Boiler Installation & Operation Manual

The Outdoor Knight Boiler - How it works... (continued)

Models 151 - 211

30

31

10

23

24

Front View - Models 151 - 211

IMG00365

IMG00365

21

11

6

Rear View - Models 151 - 211

29

IMG00366

38

39

33

15

8

14

27

13

19

1

32

22

Left Side (inside unit) - Models 151 - 211

IMG00367

10

25

28

18

7

35

4
5

36

2

26

IMG00368

Right Side (inside unit) - Models 151 - 211

20

16

34

3

1

17

5

Outdoor Knight Boiler Installation & Operation Manual

The Outdoor Knight Boiler - How it works...

Model 286

31

10

23

24

30

IMG00379

29

38

21

39

15

37

IMG00380

6

11

Front View - Model 286

18

33

15

8

14

27

13

19

20

10

36

Rear View - Model 286

34

16

4
5

25

28

2

3

1

17

32

22

IMG00381

Left Side (inside unit) - Model 286

6

IMG00382

Right Side (inside unit) - Model 286

Ratings

A

S

M

E

H

Outdoor Knight Boiler Installation & Operation Manual

Outdoor Knight Boiler

AHRI Rating

Input

Model Number

Note: Change “N” to

“L” for L.P. gas models.

OKN151 30 150 141 122 94
OKN211 42 210 197 171 94
OKN286 57 285 266 232 94

NOTICE

MBH

(Note 4)

Max Min

Maximum allowed working pressure is located on the rating plate.

Notes:

1. As an Energy Star Partner, Lochinvar has determined that
outdoor boilers meet the Energy Star guidelines for energy
efficiency.

2. The ratings are based on standard test procedures prescribed
by the United States Department of Energy.

3. Net AHRI ratings are based on net installed radiation of
sufficient quantity for the requirements of the building
and nothing need be added for normal piping and pickup.
Ratings are based on a piping and pickup allowance of 1.15.

4. Standard outdoor boilers are equipped to operate from sea
level to 4,500 feet only with no adjustments. The boiler will
de-rate by 4% for each 1,000 feet above sea level up to 4,500
feet.

5. Ratings have been confirmed by the Hydronics Section of
AHRI.

6. Outdoor boilers temperature controls comply with the
requirements of CSD-1 Section CW-400 requirements.
The manual reset high limit provided with the outdoor
boiler is listed to UL353.

Heating

Capacity

MBH

(Note 2,5)

Net

AHRI

Ratings

Water,

MBH

(Note 3,5)

AFUE

%

(Note 1, 5)

Other Specifications

Boiler

Water
Content
Gallons

1.3 1" 1/2" 3"

1.7 1" 1/2" 3"

2.4 1-1/4" 3/4" 4"

Water

Connections

Gas

Connections

Air

Size

7

Outdoor Knight Boiler Installation & Operation Manual

1 Determine boiler location

Installation must comply with:

• Local, state, provincial, and national codes, laws,
regulations, and ordinances.

• National Fuel Gas Code, ANSI Z223.1 – latest edition.

• Standard for Controls and Safety Devices for Automatically
Fired Boilers, ANSI/ASME CSD-1, when required.

• National Electrical Code.

NOTICE

 WARNING

CAUTION

The Outdoor Knight gas manifold and
controls met safe lighting and other
performance criteria when the boiler
underwent tests specified in ANSI Z21.13
– latest edition.

Outdoor models must be installed outdoors
only and must use the outdoor vent kit
assembly supplied by the manufacturer.
Personal injury or product damage may
result if any other cap is used or if an
outdoor model is used indoors. All covers,
doors and jacket panels must be properly
installed to ensure proper operation and
prevent a hazardous situation.

This product contains a condensate
management and disposal system that
may be subject to freezing if exposed
to sustained temperatures below 32°F.
Precautions should be taken to protect
the condensate trap and drain lines during
extended periods of outdoor temperatures
below 32°F.

Before locating the boiler, check:

1. Check for nearby connection to:

• Water piping

• Gas supply piping

• Electrical power

2. - Keep venting areas free of obstructions.

- Keep area clean and free of combustible and flammable
materials.

- To avoid a blocked air inlet or blocked flue condition,
keep the outdoor air inlet and flue outlet clear of leaves,
debris, etc.

CAUTION

Do not install outdoor models directly
on the ground. You must install the
outdoor unit on a concrete, brick, block or
pressure-treated wood platform.

 CAUTION

 WARNING

CAUTION

3. Check area around the boiler. Remove any combustible
materials, gasoline and other flammable liquids.

 WARNING

Do not locate unit so that high winds can
deflect off of adjacent walls, buildings
or shrubbery causing recirculation.
Recirculation of flue products may cause
operational problems, bad combustion or
damage to controls. Locate unit at least
3 feet (0.91m) from any wall or vertical
surface to prevent wind conditions from
affecting performance.

The outdoor unit must not be installed in
an area that is enclosed by walls or a fence
that will block free wind movement around
the unit. Free movement of wind around
the outdoor unit is required to carry away
the flue products and provide combustion
air. The flue outlet/combustion air inlet
of an outdoor unit must not be installed
closer than 10 feet from an inside corner of
an L-shaped structure. Walls or enclosed
fencing may cause eddy currents which
can recirculate the flue products into the
combustion air inlet. Recirculation of flue
products may cause operational problems,
bad combustion or non-warrantable damage
to controls.

- Do not install the outdoor unit under a
deck.

- Do not install an outdoor unit in a well,
stairwell, alcove, courtyard or other
recessed area.

- Do not install outdoor units on stack
frames.
Failure to comply with the above could
result in severe personal injury, death or
substantial property damage.

- Do not install outdoor units in locations
where rain from building runoff drains
will spill onto the unit.

- Do not locate the outdoor unit so that
water from sprinklers may spray directly
onto it. Water may damage controls or
other electrical components.

Failure to keep the boiler area clear and free
of combustible materials, gasoline and other
flammable liquids and vapors can result in
severe personal injury, death or substantial
property damage.

8

4. If a new boiler will replace an existing boiler, check for and
correct system problems, such as:

• System leaks causing oxygen corrosion or heat exchanger
cracks from hard water deposits.

• Incorrectly-sized expansion tank.

• Lack of freeze protection in boiler water causing system
and boiler to freeze and leak.

Outdoor Knight Boiler Installation & Operation Manual

1 Determine boiler location (continued)

Provide clearances:

Clearances from combustible materials

1. Hot water pipes—at least 1/4" (6 mm) from combustible
materials.

2. Vent pipes—minimum of 14" (356mm) from the rear and

0" on the right side from combustible materials.

Clearances for service access

1. If you do not provide the minimum clearances, it may

not be possible to service the boiler without
removing it from the space.

Recommended service clearances:

Front - 24" (610mm)
Top - 24" (610mm)
Left side - 24" (610mm)
Rear - 24" (610mm)

Outdoor vent / air intake location

 WARNING

To prevent recirculation of the flue products into the
combustion air inlet, follow all instructions in this section.

Flue gas condensate can condense on exterior walls or on the
vent. Some discoloration to exterior building or unit surfaces
can be expected. Adjacent brick or masonry surfaces should
be protected with a rust resistant sheet metal plate.

Maintain a minimum of 24" (610mm) clearance to the side
of the air inlet.

Locate the outdoor vent termination at least 48" (1.22m)
below and 48" (1.22m) horizontally from any window, door,
walkway or gravity air intake.

Locate outdoor unit at least 10 feet (3.05m) away from any
forced air inlet.

Multiple outdoor unit installations require 24" (.61m)
clearance between each vent termination.

Clearances around outdoor installations can change with
time. Do not allow the growth of trees, shrubs or other plants
to obstruct the proper operation of the outdoor vent system.

The flue products discharged from the
flue outlet on the outdoor vent may be
very hot. Avoid touching or other direct
contact with the flue gases or the vent
termination assembly. These components
are hot and direct contact can result in
burns.

Flooring and foundation

Flooring

The Outdoor Knight is approved for installation on combustible
flooring.

 WARNING

Under no circumstances is the manufacturer to be held
responsible for water damage in connection with this appliance,
or any of its components. If flooding is possible, elevate the
boiler sufficiently to prevent water from reaching the boiler.

Do not install the boiler on carpeting even if
foundation is used. Fire can result, causing
severe personal injury, death, or substantial
property damage.

Prevent combustion air contamination

Do not install unit in locations that can allow contamination
of combustion air. Refer to Table 1A for products and areas
which may cause contaminated combustion air.

Table 1A Corrosive Contaminants and Sources

Products to avoid:

Spray cans containing chloro/fluorocarbons

Permanent wave solutions

Chlorinated waxes/cleaners

Chlorine-based swimming pool chemicals

Calcium chloride used for thawing

Sodium chloride used for water softening

Refrigerant leaks
Paint or varnish removers

Hydrochloric acid/muriatic acid

Cements and glues

Antistatic fabric softeners used in clothes dryers

Chlorine-type bleaches, detergents, and cleaning solvents
found in household laundry rooms

Adhesives used to fasten building products and other similar
products

Areas likely to have contaminants

Dry cleaning/laundry areas and establishments

Swimming pools

Metal fabrication plants

Beauty shops

Refrigeration repair shops

Photo processing plants

Auto body shops

Plastic manufacturing plants

Furniture refinishing areas and establishments

New building construction

Remodeling areas

Garages with workshops

9

Outdoor Knight Boiler Installation & Operation Manual

2 Prepare boiler

Remove boiler from wood pallet

1. After removing the outer shipping carton from the boiler,

remove the installation kit.

2. Remove the front access covers to access the lag bolts in

front of the unit (FIG. 2-1).

3. To remove the boiler from the pallet (after removing the

front access covers):

a. Remove the two lag bolts from the wood pallet
inside the boiler (FIG. 2-1).
b. Detach the boiler from the lag bolts in the rear of the
unit, see FIG. 2-1.

Figure 2-2 Install Flue Pipe Assembly

WALL STRAP SCREWS

BIRD SCREEN

FLUE PIPE

WALL STRAP

NOTICE

Do not drop the boiler or bump the jacket
on the floor or pallet. Damage to the
boiler can result.

Figure 2-1 Boiler Mounted on Shipping Pallet

. 2

Install flue pipe assembly (reference FIG. 2-2 for flue

pipe assembly)

The outdoor boiler is shipped with all the necessary vent

components. All components must be installed prior to
operation. Basic installation steps are as follows:

1. Locate all venting components from the installation kit
and carton.

2. Before connecting the flue pipe sections or components,
verify the gasket is seated evenly inside the groove in the
female end of the elbow and flue adapter.

3. Remove the kit provided screws from the air cover and
use them to install the wall strap.

4. Insert the elbow into the flue adapter.

 CAUTION

Do not use grease or other lubricant
on the vent seals. Only water may be
used for this purpose. Grease or other
lubricant can make the seal brittle or it
can result in tears in the surface of the
seal, this will result in flue gas leakage.

ELBOW

NOTE: VERIFY GASKETS ARE
SEATED EVENLY INSIDE
THE GROOVE.

FLUE ADAPTER

AIR COVER

IMG00443

5. Slide the vent pipe through the wall strap and insert it
into the elbow.

6. Install the bird screen into the top of the flue pipe.

Gas conversions

 WARNING

1. Remove the top and front access covers from the unit
(tools required for removal).

2. Remove the three screws securing the gas valve to the
venturi (FIG. 2-3).

3. Locate the propane orifice disk from the conversion kit
bag. Verify that the stamping on the orifice disk matches
the boiler size (see Table 2A).

Place the orifice into the black rubber grommet in the

side of the gas valve and secure in the valve (FIG. 2-3).

4. Reposition the gas valve against the venturi and replace
the screws (FIG. 2-3) securing the valve to the venturi.

For a boiler already installed, you must
turn off gas supply, turn off power and
allow boiler to cool before proceeding.
You must also completely test the boiler
after conversion to verify performance
as described under Start-up, Section 7
of this manual. Failure to comply could
result in severe personal injury, death, or
substantial property damage.

You must install a propane orifice to
operate the outdoor boiler on propane

gas. Verify when installing that the orifice
size marking matches boiler size (Table
2A).

10

2 Prepare boiler (continued)

Outdoor Knight Boiler Installation & Operation Manual

5. After installation is complete, attach the propane
conversion label (in the conversion kit bag) next to the
boiler rating plate. Attach the LP caution label (in the
conversion kit bag) to the left side of the unit in the
lower left corner.

6. Replace the top and front access covers.

Table 2A LP Conversion Table

LP Conversion Table

Model LP Orifice Stamping

151 150
211 210 / W150
286 285

 WARNING

Figure 2-3 Installing Propane Orifice

After converting to LP, check combustion
per the Start-up procedure in Section
7 of this manual. Failure to check and
verify combustion could result in severe
personal injury, death, or substantial
property damage.

Leveling the boiler

1. Set the boiler in place and check level.
a) Adjust legs if necessary to level boiler, see FIG. 2-4
below.

Figure 2-4 Leveling Legs on the Boiler

11

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping

System water piping methods

The outdoor boiler is designed to function in a closed loop
pressurized system not less than 12 psi. A temperature and
pressure gauge is included to monitor system pressure and
outlet temperature and should be located on the boiler outlet.

It is important to note that the boiler has a minimal
amount of pressure drop and must be figured in when
sizing the circulators. Each boiler installation must have
an air elimination device, which will remove air from
the system. Install the boiler so the gas ignition system
components are protected from water (dripping, spraying,
etc.) during appliance operation for basic service of circulator
replacement, valves, and others.

Observe a minimum of 1/4 inch (6 mm) clearance around all
un-insulated hot water pipes when openings around the
pipes are not protected by non-combustible materials.

Low water cutoff device

On a boiler installed above radiation level, some states and
local codes require a low water cutoff device at the time of
installation.

Chilled water system

If the boiler supplies hot water to heating coils in air handler
units, flow control valves or other devices must be installed to
prevent gravity circulation of heater water in the coils during
the cooling cycle. A chilled water medium must be piped in
parallel with the heater.

Freeze protection, heat exchanger

Freeze protection for new or existing systems must use glycol
that is specially formulated for this purpose. This includes
inhibitors, which prevent the glycol from attacking the
metallic system components. Make certain to check that
the system fluid is correct for the glycol concentration and
inhibitor level. The system should be tested at least once
a year and as recommended by the producer of the glycol
solution. Allowance should be made for the expansion of the
glycol solution in the system piping.

 WARNING

Use only inhibited propylene glycol
solutions, which are specifically formulated
for hydronic systems. Ethylene glycol is
toxic and can attack gaskets and seals used
in hydronic systems.

General piping information

Basic steps are listed in this section along with illustrations on
the following pages (FIG.’s 3-4 thru 3-10), which will guide you
through the installation of the outdoor boiler (reference FIG.’s
3-2A and 3-2B).

1. Connect the system return marked “Inlet”.

2. Connect the system supply marked “Outlet”.

3. Install purge and balance valve or shutoff valve and drain
on system return to purge air out of each zone.

4. Install a backflow preventer on the cold feed make-up water
line.

5. Install a pressure reducing valve on the cold feed make­up water line, (15 psi nominal). Check temperature and
pressure gauge (shipped separately), which should read a
minimum pressure of 12 psi.

6. Install a circulator as shown on the piping diagrams in this
section. Make sure the circulator is properly sized for the
system and friction loss.

7. Consult the factory for a pump and/or pump cover. If a
field-supplied pump is used, install per the manufacturer’s
specifications in regard to indoor or outdoor location. An
outdoor rated pump is recommended.

8. Install an expansion tank on the system supply. Consult the
tank manufacturer’s instruction for specific information
relating to tank installation. Size the expansion tank for the
required system volume and capacity.

9. Install an air elimination device on the system supply.

10. Install a drain valve at the lowest point of the system.
Note: The boiler cannot be drained completely of water
without purging the unit with an air pressure of 15 psi.

11. This appliance is supplied with a relief valve sized in
accordance with ASME Boiler and Pressure Vessel Code,
Section IV (“Heating Boilers”). Pipe the discharge of the
safety relief valve to prevent injury in the event of pressure
relief. Provide piping that is the same size as the safety relief
valve outlet. Never block the outlet of the safety relief valve.

12

3 Hydronic piping (continued)

Outdoor Knight Boiler Installation & Operation Manual

 WARNING

The relief valve, tee and any necessary fittings

are shipped in the install kit with the boiler
and are to be field installed (FIG. 3-1).

*See the piping illustrations included in this section, FIG.’s 3-4
thru 3-10 for suggested guidelines in piping the outdoor boiler
with either zone valves or circulator pumps.

NOTICE

*Please note that these illustrations are
meant to show system piping concept only,
the installer is responsible for all equipment
and detailing required by local codes.

CAUTION

The outdoor boiler is capable of servicing
multiple temperature loop systems. It is the
responsibility of the installer to protect the
loops with lower temperature requirements
from higher temperatures that may be
required by other loops.

Relief valve and temperature and pressure
gauge installation

Basic steps are listed below to guide you through the installation
of the relief valve and the temperature and pressure (T & P)
gauge provided with the unit.

1. Install the tee with the 3/4 inch fitting positioned
vertically and on the top as shown in FIG. 3-1.

2. Install the relief valve into the 3/4 inch fitting of the tee
installed in Step 1 (FIG. 3-1).

3. Install a field provided 5 inch long nipple and tee with the
fitting positioned vertically on the top on the
downstream side of the relief valve (see FIG. 3-1).

4. Install the temperature and pressure gauge provided with
the unit into the top fitting of the tee (a bushing may be
necessary) installed in Step 3 (FIG. 3-1).

Figure 3-1 Relief Valve / T & P Installation

RELIEF VALVE

TEMPERATURE &
PRESSURE GAUGE

TEE W/FITTING ON TOP
(FIELD PROVIDED)

CLOSE NIPPLE
(FIELD PROVIDED)

TEE WITH 3/4" FITTING
ON TOP

CLOSE NIPPLE

IMG00369

Near boiler piping components

1. Boiler system piping:

Boiler system piping MUST be sized per the pipe
requirements listed in Table 3A. Reducing the pipe size
can restrict the flow rate through the boiler, causing
inadvertent high limit shutdowns and poor system
performance. Flow rates are based on 20 feet of piping,
4 - 90° elbows, and 2 - fully ported ball valves.

2. Boiler system pump w/pump cover:

A Grundfos UPS26-99F pump and pump cover will be
provided by the factory (for standard altitude models) as
the boiler circulation pump based on 20 feet of piping,

4 - 90° elbows, and 2 - fully ported ball valves.

Outdoor boilers are capable of controlling a
variable speed boiler circulator. Variable speed circulators
MUST be sized to meet the specified minimum flow
requirements listed in FIG. 3-3 on page 15 at full

speed.

3. Domestic hot water circulating pump:

Field supplied. The pump MUST be sized to meet
the specified minimum flow requirements listed in
FIG. 3-3. Consult the indirect water heater operating
guide to determine flow characteristics for the selected
product used.

4. Boiler isolation valves:

Field supplied. Full port ball valves are required.
Failure to use full port ball valves could result in a
restricted flow rate through the boiler.

5. Check valves:

Field supplied. Check valves are recommended for
installation as shown in FIG.’s 3-4 thru 3-10. Failure to
install check valves could result in a reverse flow
condition during pump(s) off cycle.

6. Domestic indirect hot water isolation valves:

Field supplied. Full port ball valves are required. Failure
to use full port ball valves could result in a restricted flow
rate through the boiler.

7. Anti-scald mixing valve:

Field supplied. An anti-scald mixing valve is
recommended when storing domestic hot water above
115°F.

8. Unions:

Field supplied. Recommended for unit serviceability.

9. Temperature and pressure gauge:

Factory supplied. The temperature and pressure gauge is
shipped loose. It is the responsibility of the contractor to
install the temperature and pressure gauge on the boiler
water outlet.

10. Pressure relief valve:

Factory supplied. The pressure relief valve is sized to
ASME specifications.

11. Boiler purge valve:

Field supplied. The boiler purge valve is used to
remove entrapped air from the heat exchanger during
start-up.

13

3 Hydronic piping

Outdoor Knight Boiler Installation & Operation Manual

12. System temperature sensor:

Lochinvar supplies a system temperature sensor.
The sensor is to be installed in the heating loop
downstream from the boiler hot water piping and
heating loop junction. Typically the sensor will be
located far enough downstream to sense system diluted
water temperature.

13. Indirect water heaters:

The outdoor boiler may be piped to an indirect
water heater to heat domestic hot water with the space heat
transfer medium. As depicted on pages 17 through 23
there are two options when utilizing an indirect water
heater.

A. The space heating piping will branch off to flow the
space heat transfer medium through a single wall
heat exchanger coil inside the indirect water heater.

B. The indirect water heater is connected to the system
supply piping. A pump controlled by the
outdoor boiler’s control will regulate the flow of
water through the indirect water heater. The indirect
water heater’s temperature will be regulated by the
outdoor boiler’s control.

The outdoor boiler is pre-configured to control the
operation of the DHW pump with Domestic Hot Water
Prioritization programming. The DHW programming is
designed to control and balance the space heating
demand by switching between DHW and space heating.

Lochinvar offers the Squire which is a series of indirect
water heaters. The Squire features a stainless steel vessel
with a single wall stainless steel heat exchanger.

CAUTION

It is up to the installer to ensure the
minimum system flow is not less than the
minimum boiler flow at any time.

 WARNING

The National Standard Plumbing Code
and the Uniform Plumbing Code limit the
pressure of the heat transfer fluid to less
than the minimum working pressure of the
potable water system up to 30 psi maximum.
Also, the heat transfer fluid must be water
or other non-toxic fluid having a toxicity of
Class 1, as listed in Clinical Toxicology of
Commercial Products, 5th Edition.

14. Y-Strainer:

Field supplied. A Y-strainer or equivalent multipurpose
strainer is recommended at the inlet of the heat exchanger
to remove system particles from older hydronic systems and
protect newer systems.

Circulator sizing

The outdoor boiler heat exchanger does have a pressure drop,
which must be considered in your system design. Refer to the
graph in FIG. 3-3 for pressure drop through the outdoor boiler
heat exchanger.

Near boiler piping connections

Figure 3-2A Near Boiler Piping w/Y-Strainer

FROM SYSTEM

Y-STRAINER

(RECOMMENDED)

SYSTEM
PUMP

TO SYSTEM

14

BOILER
PUMP

DRAIN
(TYPICAL)

TO FLOOR

DRAIN

DOMESTIC HOT
WATER PUMP

O

T

FROM

INDIRECT

DOMESTIC

HOT WATER

TANK

IMG00377

Figure 3-2B Near Boiler Piping w/Low Loss Header

AIR VENT VALVE

LOW LOSS HEADER

(TYPICAL)

Y-STRAINER

(RECOMMENDED)

BOLIER PUMP

SYSTEM SENSOR

AIR SEPARATOR

DRAIN VALVE

TO FLOOR
DRAIN

DRAIN
(TYPICAL)

FILL VALVE

M

O

R

F

INDIRECT

DOMESTIC

HOT WATER

O

T

M

E

T

S

Y

S

O

T

S

M

O

R

F

EXPANSION TANK

IMG00378

M

E

T

S

Y

0

5

10

15

20

25

3 4 5 6 7 8 9 10111213141516171819202122232425

151

211

286

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping (continued)

Figure 3-3 Pressure Drop vs. Flow

Pressure Drop vs. Flow (Includes Secondary Piping)

Pressure Drop (Feet of Head)

Flow Rate (GPM)

Table 3A Circulator Recommendations for Temperature Rise Applications_20°, 25°, and 35°

20°F Temperature Rise Applications

Model GPM FT/HD

Minimum Pipe

Size

Grundfos TACO B & G Armstrong

151 14 20 1" UPS26-99F 0011 NRF-36 E7
211 20 29 1" UPS32-160 1400-50 PL-55 E9*
286 27 15 1-1/4" UPS32-80 1400-20 PL-36 E11

*NOTICE

These pumps are only slightly above 20° rise flows, but are the closest available. To reach a 20° rise or less, an
upsized pump will be required.

Pump

25°F Temperature Rise Applications

Model GPM FT/HD

Minimum Pipe

Size

Grundfos TACO B & G Armstrong

151 11 13 1" UPS26-99F 0014 NRF-36 E7
211 16 19 1" UPS26-99F 0013 NRF-36 E7
286 21 12 1-1/4" UPS26-99F 0011 NRF-36 E7

Pump

35°F Temperature Rise Applications

Model GPM FT/HD

Minimum Pipe

Size

Grundfos TACO B & G Armstrong

151 810 1" UPS15-58FC 008/0010 NRF-36 Astro-30
211 11 9 1" UPS15-58FC 0010 NRF-36 Astro-50
286 15 7 1-1/4" UP26-64F 008/0010 NRF-36 E7

Pump

NOTICE

NOTICE

NOTICE

Pumps listed in bold type are provided by the factory as the boiler circulation pump on standard altitude
models.

Pumps listed in italicized type are provided by the factory as the boiler circulation pump on high altitude
models.

The temperature rise provided by a pump/model combination will decrease by 3% per 1000 feet of elevation.

15

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping

Variable speed pump option

Table 3B Recommended Variable Speed Pumps

Minimum Temperature Rise*

Pump

Model

151 21 20 19
211 27 25 24
286 27 24 22

*The minimum temperature rise is derived from the chart in FIG. 3-3 with the firing rate and pump speed at 100% as shown in
the table above.

The shaded regions of pump coverage are only available for applications with 230V (60 Hz) supply voltage, all others are

to be 115V. (A field supplied relay is required to connect the 230V pump listed in the shaded area in Table 3B to the boiler
high voltage terminal strip.)

Grundfos

UP26-96 FC/VS

TACO

0013 IFC VS

Wilo

Stratos 1.25 3 x 30

Variable speed pump setup

Before operation, ensure the following:

- Pump is set for an input signal of 0 - 10Vdc by the dip switches on the pump control

- Pump is set for external signal control (if applicable)

- Pump is set for linear output (if applicable)

- If pump does not come equipped with a 0 - 10 Vdc input option, an optional module
will be required from the vendor

NOTICE

NOTICE

Pump sizing and flow requirements are
based on 20 feet of piping, 4 - 90°
elbows, and 2 - fully ported ball valves.

It is required that near boiler piping
systems utilize the Primary/Secondary
configuration shown in FIG. 3-10 only.
The use of other near boiler piping
configurations could result in improper
building and system flow rates leading to
inadvertent boiler high limit shutdowns
and poor system performance.

SMART SYSTEM / Multi-temperature loop
control option

The outdoor boiler is capable of producing up to three (3) set
point temperatures to meet different space heating demands.
When using more than one temperature demand it is necessary
to protect the lower temperature loop from overheating. To
help aid with this protection, Lochinvar offers the Multi­Temperature Loop Control Board Kit (RLY30086).

16

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping (continued)

Figure 3-4 Single Boiler - Single Temperature Zoned with Circulators

ZONE #1

PRESSURE

REDUCING VALVE

BACKFLOW

PREVENTER

MAKE UP WATER

AIR SEPARATOR

BALL VALVE

(TYPICAL)

DRAIN POINT

(TYPICAL)

PRESSURE

GAUGE

SYSTEM SUPPLY

SENSOR

(WHEN USED)

ZONE #2 ZONE #3 ZONE #4

EXPANSION

TANK

MAY SUBSTITUTE LOW LOSS HEADER

Y-STRAINER
(RECOMMENDED)

BOILER
CIRCULATOR

DOMESTIC

HOT WATER

CIRCULATOR

FLOW CHECK

ZONE CIRCULATORS

ANTI-SCALD

MIXING VALVE

VALVE

(TYPICAL)

(TYPICAL)

HOT

WATER

OUT

COLD

WATER

IN

TEMPERATURE /

NOTICE

Please note that these illustrations are meant to show system piping concept only, the installer is responsible
for all equipment and detailing required by local codes.

Indoor tank shown for illustration purposes.

UNION

(TYPICAL)

PRESSURE

GAUGE

DRAIN

BOILER

INDIRECT

DHW TANK

IMG00370

17

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping

Figure 3-5 Multiple Boilers - Single Temperature Zoned with Circulators

REDUCING VALVE

BACKFLOW

PREVENTER

MAKE UP WATER

AIR SEPARATOR

MAY SUBSTITUTE

LOW LOSS HEADER

PRESSURE

PRESSURE

GAUGE

SYSTEM SUPPLY

SENSOR

Model

151 2" 2" 2-1/2" 2-1/2" 3" 3" 3-1/2"
211 2" 2-1/2" 3" 3" 3-1/2" 4" 4"
286 2-1/2" 2-1/2" 3" 3-1/2" 3-1/2" 4" 5"

ZONE #1

ZONE #2

EXPANSION

TANK

2345678

ZONE #3

Number of Units

Required Pipe Sizes

ZONE #4

FLOW CHECK

VALVE

(TYPICAL)

ZONE CIRCULATORS

(TYPICAL)

BALL VALVE

(TYPICAL)

DRAIN POINT

(TYPICAL)

TEMPERATURE /

PRESSURE

GAUGE

Y-STRAINER
(RECOMMENDED)
(TYPICAL)

BOILER 2

(MEMBER 1)

NOT TO EXCEED 4 PIPE DIA OR MAX. OF 12" APART

ANTI-SCALD

MIXING VALVE

DOMESTIC

HOT WATER

CIRCULATOR

UNION

(TYPICAL)

BOILER
CIRCULATOR

DRAIN

BOILER 1

(LEADER)

HOT

WATER

OUT

COLD

WATER

IN

INDIRECT

DHW TANK

NOTICE

Please note that these illustrations are meant to show system piping concept only, the installer is responsible
for all equipment and detailing required by local codes.

Indoor tank shown for illustration purposes.

18

IMG00371

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping (continued)

Figure 3-6 Single Boiler - Multiple Temperatures

PRESSURE
REDUCING VALVE

BACKFLOW

PREVENTER

MAKE

UP

WATER

AIR SEPARATOR

BALL VALVE

(TYPICAL)

DRAIN POINT

(TYPICAL)

PRESSURE

GAUGE

SYSTEM

SUPPLY
SENSOR

EXPANSION

TANK

MAY SUBSTITUTE
LOW LOSS HEADER

TEMPERATURE

LOOP #1

NOT TO EXCEED 4 PIPE DIA
OR MAX. OF 12" APART

Y-STRAINER
(RECOMMENDED)

BOILER
CIRCULATOR

FLOW CHECK
VALVE

SHIELDED CABLE TO

BOILER CONTROL

TEMPERATURE

LOOP #2

120VAC TO PUMPS

MIXING VALVES

DOMESTIC

HOT WATER

CIRCULATOR

TEMPERATURE

24V SIGNALTO

LOOP #3

HOT WATER

OUT

WIRES TO
LOOP SENSORS

MIXING VALVES

(TYPICAL)

MULTI-TEMP
LOOP CONTROL

ANTI-SCALD
MIXING VALVE

COLD
WATER
IN

CAUTION

NOTICE

Mixing valves are required for the protection of low temperature loops.

Please note that these illustrations are meant to show system piping concept only, the installer is responsible
for all equipment and detailing required by local codes.

Indoor tank shown for illustration purposes.

UNION

(TYPICAL)

TEMPERATURE /

PRESSURE

GAUGE

DRAIN

INDIRECT

DHW TANK

BOILER

IMG00372

19

3 Hydronic piping

Outdoor Knight Boiler Installation & Operation Manual

Figure 3-7 Multiple Boilers - Multiple Temperatures

BACKFLOW

PREVENTER

MAKE

UP

WATER

AIR SEPARATOR

PRESSURE
REDUCING VALVE

PRESSURE

GAUGE

EXPANSION

MAY SUBSTITUTE
LOW LOSS HEADER

SYSTEM
SUPPLY
SENSOR

TANK

TEMPERATURE

LOOP #1

Number of Units

Model

2345678

Required Pipe Sizes

151 2" 2" 2-1/2" 2-1/2" 3" 3" 3-1/2"
211 2" 2-1/2" 3" 3" 3-1/2" 4" 4"
286 2-1/2" 2-1/2" 3" 3-1/2" 3-1/2" 4" 5"

WIRES TO

LOOP

TEMPERATURE

LOOP #2

TEMPERATURE

LOOP #3

MIXING VALVES

SENSORS

(TYPICAL)

24V
SIGNAL
TO MIXING
VALVES

BALL VALVE

(TYPICAL)

DRAIN POINT

(TYPICAL)

Y-STRAINER
(RECOMMENDED)

UNION
(TYPICAL)

BOILER

NOT TO EXCEED 4 PIPE DIA OR MAX. OF 12" APART

BOILER
CIRCULATOR

FLOW CHECK

VALVE

TEMPERATURE /

PRESSURE

GAUGE

DRAIN

120VAC TO PUMPS

MULTI-TEMP

LOOP CONTROL

(OPTIONAL)

DOMESTIC

HOT WATER

CIRCULATOR

BOILER

SHIELDED CABLE TO
BOILER CONTROL

ANTI-SCALD

MIXING

VALVE

INDIRECT

DHW TANK

HOT

WATER

OUT

COLD
WATER
IN

IMG00373

CAUTION

NOTICE

Mixing valves are required for the protection of low temperature loops.

Please note that these illustrations are meant to show system piping concept only, the installer is responsible
for all equipment and detailing required by local codes.

Indoor tank shown for illustration purposes.

20

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping (continued)

Figure 3-8 Single Boiler - Multiple Temperatures with DHW Piped as a Zone

BACKFLOW

PREVENTER

MAKE

UP

WATER

(RECOMMENDED)

AIR SEPARATOR

BALL VALVE

(TYPICAL)

DRAIN POINT

(TYPICAL)

Y-STRAINER

BOILER
CIRCULATOR

PRESSURE
REDUCING VALVE

PRESSURE

GAUGE

EXPANSION

TEMPERATURE

LOOP #1

MIXING VALVES

(TYPICAL)

SYSTEM

SUPPLY
SENSOR

TANK

MAY SUBSTITUTE
LOW LOSS HEADER

NOT TO EXCEED 4 PIPE DIA OR MAX. OF 12" AP ART

DOMESTIC
HOT WATER
CIRCULATOR

FLOW

CHECK

VALVE

TEMPERATURE

LOOP #2

24V SIGNAL TO

MIXING VALVES

120VAC TO PUMPS

MULTI-TEMP TO

LOOP CONTROL

TEMPERATURE

LOOP #3

SHIELDED CABLE TO
BOILER CONTROL

HOT WATER

OUT

WIRES TO
LOOP
SENSORS

ANTI-SCALD
MIXING VALVE

COLD
WATER
IN

UNION

(TYPICAL)

DRAIN

BOILER

CAUTION

NOTICE

Mixing valves are required for the protection of low temperature loops.

Please note that these illustrations are meant to show system piping concept only, the installer is responsible
for all equipment and detailing required by local codes.

Indoor tank shown for illustration purposes.

NOTICE

Please note that the installer is responsible for ensuring DHW prioritization when piped as a zone.

Indoor tank shown for illustration purposes.

PRESSURE

TEMPERATURE /

PRESSURE GAUGE

RELIEF

VALVE

BOILER

INDIRECT

DHW TANK

IMG00374

21

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping

Figure 3-9 Multiple Boilers - Single Temperature Zoned with Valves

Model

151 2" 2" 2-1/2" 2-1/2" 3" 3" 3-1/2"
211 2" 2-1/2" 3" 3" 3-1/2" 4" 4"
286 2-1/2" 2-1/2" 3" 3-1/2" 3-1/2" 4" 5"

ZONE #2

ZONE #3 ZONE #4

BACKFLOW

PREVENTER

BALL VALVE

(TYPICAL)

PRESSURE

REDUCING VALVE

PRESSURE

GAUGE

ZONE #1

Number of Units

2345678

Required Pipe Sizes

ZONE VALVES

(TYPICAL)

MAKE UP WATER

AIR SEPARATOR

SYSTEM SUPPLY

(WHEN USED)

DRAIN POINT

(TYPICAL)

SENSOR

SYSTEM

CIRCULATOR

Y-STRAINER
(RECOMMENDED)
(TYPICAL)

EXPANSION

TANK

DIFFERENTIAL
PRESSURE BYPASS
VALVE (IF USED)

MAY SUBSTITUTE LOW LOSS HEADER

NOT TO EXCEED 4 PIPE DIA OR MAX. OF 12" APART

ANTI-SCALD

BOILER
CIRCULATOR

MIXING VALVE

DOMESTIC

HOT WATER

CIRCULATOR

HOT

WATER

OUT

COLD

WATER

IN

TEMPERATURE /

PRESSURE

GAUGE

BOILER 2

(MEMBER 1)

NOTICE

Please note that these illustrations are meant to show system piping concept only, the installer is responsible
for all equipment and detailing required by local codes.

Indoor tank shown for illustration purposes.

22

UNION

(TYPICAL)

DRAIN

BOILER 1
(LEADER)

INDIRECT

DHW TANK

IMG00375

Outdoor Knight Boiler Installation & Operation Manual

3 Hydronic piping (continued)

Figure 3-10 Multiple Boilers - Non-Zoned Primary/Secondary Piping

Model

151 2" 2" 2-1/2" 2-1/2" 3" 3" 3-1/2"
211 2" 2-1/2" 3" 3" 3-1/2" 4" 4"
286 2-1/2" 2-1/2" 3" 3-1/2" 3-1/2" 4" 5"

PRESSURE

REDUCING VALVE

BACKFLOW

PREVENTER

MAKE UP WATER

CIRCULATOR

TO

SYSTEM

BALL VALVE

(TYPICAL)

SYSTEM

EXPANSION

TANK

PRESSURE

GAUGE

SYSTEM SUPPLY
SENSOR

AIR SEPARATOR

Number of Units

2345678

Required Pipe Sizes

MAY SUBSTITUTE LOW LOSS HEADER

FROM

NOT TO EXCEED 4 PIPE DIA OR MAX. OF 12" APART

DRAIN POINT

(TYPICAL)

Y-STRAINER

(RECOMMENDED)

(TYPICAL)

SYSTEM

TEMPERATURE /

PRESSURE

GAUGE

BOILER 4

(MEMBER 3)

BOILER 3

(MEMBER 2)

UNION

(TYPICAL)

BOILER
CIRCULATOR

BOILER 2

(MEMBER 1)

DRAIN

ANTI-SCALD

MIXING VALVE

DOMESTIC

HOT WATER

CIRCULATOR

BOILER 1

(LEADER)

HOT

WATER

OUT

COLD WATER

INDIRECT

DHW TANK

IMG00376

IN

NOTICE

Please note that these illustrations are meant to show system piping concept only, the installer is responsible
for all equipment and detailing required by local codes.

Indoor tank shown for illustration purposes.

23

4 Gas connections

Outdoor Knight Boiler Installation & Operation Manual

Connecting gas supply piping

1. Remove the top access cover and refer to FIG. 4-1 to pipe
gas to the boiler.

a. Install ground joint union for servicing, when

required.

b. Install a manual shutoff valve in the gas supply

piping outside boiler jacket when required by local
codes or utility requirements.

2. Install sediment trap / drip leg.

Figure 4-1 Gas Supply Piping

UNION

GAS SUPPLY

4. Purge all air from the gas supply piping.

5. Before placing the boiler in operation, check the boiler
and its gas connection for leaks.

a. The appliance must be disconnected from the gas

supply piping system during any pressure testing of
that system at a test pressure in excess of 1/2 PSIG
(3.5 kPa).

b. The appliance must be isolated from the gas supply
piping system by closing a manual shutoff valve
during any pressure testing of the gas supply piping
system at test pressures equal to or less than 1/2 PSIG
(3.5 kPa).

c. The appliance and its gas connection must be leak
tested before placing it in operation.

 WARNING

Do not check for gas leaks with an open
flame – use the bubble test. Failure to
use the bubble test or check for gas leaks
can cause severe personal injury, death, or
substantial property damage.

6. Use pipe sealing compound compatible with propane

gases. Apply sparingly only to male threads of the pipe
joints so that pipe dope does not block gas flow.

DRIP
LEG

MANUAL
SHUTOFF VALVE
(FIELD SUPPLIED)

IMG00383

3. Support piping with hangers, not by the boiler or its
accessories.

 WARNING

The gas valve and blower will not support
the weight of the piping. Do not attempt
to support the weight of the piping with
the boiler or its accessories. Failure to
comply could result in severe personal
injury, death, or substantial property
damage.

 WARNING

 WARNING

Failure to apply pipe sealing compound as
detailed in this manual can result in severe
personal injury, death, or substantial
property damage.

Outdoor boilers are typically shipped
ready to fire on natural gas. Check boiler
rating plate to determine which fuel the
boiler is set for. If set to natural gas, it may
be converted to LP by installing an orifice
(see page 11). In order to operate on LP
gas, an orifice MUST BE installed. Failure
to comply could result in severe personal
injury, death, or substantial property
damage.

24

Outdoor Knight Boiler Installation & Operation Manual

4 Gas connections (continued)

 WARNING

Figure 4-2 Inlet Pipe with Backup Wrench

Use two wrenches when tightening gas
piping at boiler (FIG. 4-2), using one
wrench to prevent the boiler gas line
connection from turning. Failure to
support the boiler gas connection pipe to
prevent it from turning could damage gas
line components.

Natural gas:

Pipe sizing for natural gas

1. Refer to Table 4A for pipe length and diameter. Based on
rated boiler input (divide by 1,000 to obtain cubic feet per
hour).

a. Table 4A is only for natural gas with specific gravity

0.60 inches, with a pressure drop through the gas
piping of 0.5 inches w.c.

b. For additional gas pipe sizing information, refer to

ANSI Z223.1 (or B149.1 for Canadian installations).

Natural gas supply pressure requirements

1. Pressure required at the gas valve inlet pressure port:

• Maximum 14 inches w.c. with no flow (lockup) or
with boiler on.

• Minimum 4 inches w.c. with gas flowing (verify during
boiler startup).

2. Install 100% lockup gas pressure regulator in supply line if
inlet pressure can exceed 14 inches w.c. at any time. Adjust
lockup regulator for 14 inches w.c. maximum.

USE BACKUP WRENCH
TO PREVENT PIPE FROM
ROTATING

NOTICE

Maximum inlet gas pressure must not
exceed the value specified. Minimum
value listed is for the purposes of input
adjustment.

IMG00384

Propane Gas:

 WARNING

Pipe sizing for propane gas

1. Contact gas supplier to size pipes, tanks, and 100% lockup
gas pressure regulator.

Propane Supply Pressure Requirements

1. Adjust propane supply regulator provided by the gas
supplier for 14 inches w.c. maximum pressure.

2. Pressure required at gas valve inlet pressure port:

• Maximum 14 inches w.c. with no flow (lockup) or with
boiler on.

• Minimum 8 inches w.c. with gas flowing (verify during
boiler startup).

Outdoor boilers are typically shipped ready
to fire on natural gas. Check boiler rating
plate to determine which fuel the boiler is set
for. If set to natural gas, it may be converted
to LP by installing an orifice (see page 11).
In order to operate on LP gas, an orifice
MUST BE installed. Failure to comply
could result in severe personal injury, death,
or substantial property damage.

 WARNING

Ensure that the high gas pressure regulator
is at least 6 - 10 feet upstream of the
appliance.

25

4 Gas connections

Table 4A Natural Gas Pipe Size Chart

Outdoor Knight Boiler Installation & Operation Manual

Nominal

Iron Pipe

Size (Inches)

1/2
3/4

1
1-1/4
1-1/2

2
2-1/2

3

4

 WARNING

10

175 120 97 82 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
369

697
1400
2150
4100
6460

11200
23500

20

256
477

974
1500
2820
4460
7900

16100

30

205
384

789
1210
2260
3610
6400

13100

11100

Outdoor boilers are typically shipped ready to fire on natural gas. Check boiler rating plate to determine
which fuel the boiler is set for. If set to natural gas, it may be converted to LP by installing an orifice (see page

11). In order to operate on LP gas, an orifice MUST BE installed. Failure to comply could result in severe
personal injury, death, or substantial property damage.

Check inlet gas supply

NOTICE

 WARNING

The gas piping must be sized for the proper flow and length
of pipe, to avoid excessive pressure drop. Both the gas meter
and the gas regulator must be properly sized for the total gas
load.

If you experience a pressure drop greater than 1 inch w.c.,
the meter, regulator, or gas line is undersized or in need of
service. Perform the steps below when checking inlet gas
supply:

1. Turn the main power switch to the “OFF” position.

2. Shut off gas supply at the manual gas valve in the gas
piping to the appliance.

26

CSA or UL listed flexible gas connections
are acceptable, but you must exercise
caution to ensure that the line has adequate
capacity to allow your boiler to fire at full
rate. Consult with local codes for proper
installation or service procedures.

DO NOT adjust gas valve outlet pressure.
The gas valve is factory-set for the correct
outlet pressure. This setting is suitable
for natural gas and propane, requiring
no field adjustment. Attempting to
alter the gas valve outlet pressure could
result in damage to the valve, causing
potential severe personal injury, death, or
substantial property damage.

Single Unit

Natural Gas Pipe Capacity Chart

Length of Pipe in Straight Feet for 1/2 PSI

40

174
328

677
1020
1950
3100
5400

50

155
292
595

923
1720
2720
4870

10000

60

141
267
543

830
1560
2460
4410
9000

70

128
246
502

769
1440
2310
4000
8300

80

121
236
472

707
1330
2100
3800
7690

90

113
210
441

666
1250
2000
3540
7380

100

106
200
410

636
1180
1900
3330
6870

3. Loosen the set screw one (1) full turn from inside the
pressure tap on top of the gas valve. Place the tubing of
the manometer over the tap once the set screw is
loosened as shown in FIG. 4-3.

4. Slowly turn on the gas supply at the field installed
manual gas valve.

5. Turn the power switch to the “ON” position.

6. Adjust the temperature set point on the control panel of
the SMART SYSTEM control module to call for heat.

7. Observe the gas supply pressure as the burner fires at
100% of rated input. Percent of burner input will be
displayed on the control panel.

8. Ensure inlet pressure is within specified range.
Minimum and maximum gas supply pressures are
specified in this section of the manual.

9. If gas supply pressure is within normal range and no
adjustments are needed, proceed on to Step 11.

10. If the gas pressure is out of range, contact the gas utility,
gas supplier, qualified installer or service agency to
determine the necessary steps to provide proper gas
pressure to the control.

11. Turn the power switch to the “OFF” position.

12. Shut off the gas supply at the manual gas valve in the gas
piping to the appliance.

13. Remove the manometer from the pressure tap on top of
the gas valve. Re-tighten the set screw inside the pressure
tap.

125

95
179
369
564

1100
1700
3000
6150

150

86
164
333
513
974

1540
2720
5640

175

79
149
308
472
871

1400
2500
5130

200

74
138
287
441
820

1300
2340
4720

Outdoor Knight Boiler Installation & Operation Manual

4 Gas connections (continued)

 WARNING

14. Turn on the gas supply at the manual gas valve.

15. Turn the power switch to the “ON” position.

16. Adjust the temperature set point on the control panel of
the SMART SYSTEM control module to the desired
water temperature so the appliance will call for heat.

17. Check burner performance by cycling the system while
you observe burner response. The burner should ignite
promptly. Flame pattern should be stable. Turn system
off and allow burner to cool, then cycle burner again to
ensure proper ignition and flame characteristics.

Figure 4-3 Inlet Gas Supply Check

LOOSEN THE SET SCREW ONE (1) FULL TURN
AND PLACE THE MANOMETER TUBING OVER
THE PRESSURE TAP.

When re-tightening the set screw, be sure
to tighten securely to prevent gas leaks.

Do not check for gas leaks with an open
flame -- use the bubble test. Failure to
use the bubble test or check for gas leaks
can cause severe personal injury, death, or
substantial property damage.

Gas Pressure

The gas pressure must remain between 4 inches w.c. (natural),
8 inches w.c. (LP) minimum and 14 inches w.c. (natural and
LP) maximum during stand-by (static) mode and while in
operating (dynamic) mode. If an in-line regulator is used, it
must be a minimum of 10 feet from the outdoor boiler. It is
very important that the gas line is properly purged by the gas
supplier or utility company. Failure to properly purge the
lines or improper line sizing, will result in ignition failure.

The problem is especially noticeable in NEW LP installations
and also in empty tank situations. This can also occur when
a utility company shuts off service to an area to provide
maintenance to their lines.

Gas valve replacement

The gas valve MUST NOT be replaced with a conventional
gas valve under any circumstances. As an additional safety
feature, this gas valve has a flanged connection to the venturi
and blower.

 WARNING

Failure to follow all precautions could
result in fire, explosion, or death!

DETAIL

IMG00385

 WARNING

DO NOT adjust gas valve outlet pressure.
The gas valve is factory-set for the correct
outlet pressure. This setting is suitable
for natural gas and propane, requiring
no field adjustment. Attempting to
alter the gas valve outlet pressure could
result in damage to the valve, causing
potential severe personal injury, death, or
substantial property damage.

27

5 Field wiring

Outdoor Knight Boiler Installation & Operation Manual

 WARNING

NOTICE

NOTICE

ELECTRICAL SHOCK HAZARD – For
your safety, turn off electrical power supply
before making any electrical connections
to avoid possible electric shock hazard.
Failure to do so can cause severe personal
injury or death.

Wiring must be N.E.C. Class 1.
If original wiring as supplied with boiler

must be replaced, use only type 105°C wire
or equivalent.

Boiler must be electrically grounded as
required by National Electrical Code ANSI/
NFPA 70 – latest edition.

All wiring exterior to the appliance must be
enclosed in approved conduit.

In accordance with Section 303 of the 2007
Energy Act, this boiler is equipped with a
feature that saves energy by reducing the
boiler water temperature as the heating
load decreases. This feature is equipped
with an override, which is provided
primarily to permit the use of an external
energy management system that serves the
same function. This override MUST NOT
be used unless at least one of the following
conditions is true:

1. An external energy management
system is installed that reduces the
boiler water temperature as the heating
load decreases.

2. This boiler is not used for any space
heating.

3. This boiler is part of a modular or
multiple boiler system having a total
input of 300,000 Btu/hr or greater.

4. This boiler is equipped with a tankless
coil.

 CAUTION

Label all wires prior to disconnection
when servicing controls. Wiring errors
can cause improper and dangerous
operation.

Installation must comply with:

1. National Electrical Code and any other national, state,
provincial, or local codes, or regulations.

Line voltage connections

1. Connect 120 vac power wiring to the line voltage terminal
strip in the junction box, as shown in FIG. 5-1.

2. Provide and install a fused disconnect or service switch
(15 amp recommended) as required by the code (see
FIG. 5-1).

3. The boiler pump is shipped loose. Wire the boiler pump
as shown in FIG. 5-1.

4. When connecting a domestic hot water (DHW) pump,
connect the wiring to the line voltage terminal strip as
shown in FIG. 5-1.

5. To activate a system pump, wire as shown in FIG. 5-1.
If the motor is larger than 1/8 hp or 1.8 amps, you must
isolate with a relay.

Low voltage connections

1. Route all low voltage wires through the knockouts in the

rear of the boiler, as shown in FIG. 5-2.

2. Connect low voltage wiring to low voltage connection

board as shown in FIG. 5-3 on page 31 of this manual and
the boiler wiring diagram.

Figure 5-2 Routing Field Wiring

Figure 5-1 Line Voltage Field Wiring Connections

28

LOW VOLTAGE
CONNECTION
BOARD

LOW VOLTAGE
WIRING
KNOCKOUTS

LINE VOLTAGE
WIRING KNOCKOUTS

IMG00386

5 Field wiring (continued)

Outdoor Knight Boiler Installation & Operation Manual

Thermostat

1. Connect the room thermostats or end switches (isolated
contact only) to Heat/Loop Demand 1, 2, or 3, as shown
in FIG. 5-3.

2. Install the thermostat on the inside wall away from
influences of drafts, hot or cold water pipes, lighting
fixtures, television, sunlight, or fireplaces.

3. Thermostat anticipator (if applicable):

a. If connected directly to boiler, set for 0.1 amps.
b. If connected to relays or other devices, set to match

total electrical power requirements of connected
devices. See device manufacturers’ specifications
and thermostat instructions for details.

Outdoor temperature sensor

In the absence of an external energy management system, an
outdoor temperature sensor must be used.

1. Mount the sensor on an exterior wall, shielded from
direct sunlight or flow of heat or cooling from other
sources.

2. Route sensor wires through a knockout at the rear of the
boiler (see FIG. 5-2).

3. Connect the outdoor temperature sensor (FIG. 5-3) to
the outdoor sensor terminals on the connection board to
enable outdoor reset operation of the outdoor boiler.

DHW thermostat

Connect storage indirect water heater (DHW) thermostat
(FIG. 5-3) to the DHW thermostat terminals on the
connection board. If a tank sensor is connected (see DHW
Tank Sensor below) the tank thermostat is ignored.

DHW tank sensor

1. By installing a tank sensor, the SMART SYSTEM control

can perform the tank thermostat function. The SMART
SYSTEM control automatically detects the presence of
this sensor and generates a DHW call for heat when
the tank temperature drops 6°F (3°C) below the tank
set point and finishes the call for heat when the tank
temperature reaches the tank set point.

2. The tank sensor included with the Lochinvar Squire

Indirect DHW tank (TST20015) is the only sensor
suitable for use with the SMART SYSTEM control.
Connect the sensor leads to the Tank Sensor terminals on
the Low Voltage Connection Board (FIG. 5-3).

 WARNING

Failure to use the correct sensor may result
in the tank temperature being either above
or below the set point.

High gas pressure switch

If a switch is provided to detect excessive gas pressure, remove
the jumper wire from the terminals on the connection board,
and then connect them to its normally closed contacts (FIG.
5-3).

Low gas pressure switch

1. If a switch is provided to detect low gas pressure, remove the
jumper wire from the terminals on the connection board
and connect them to its normally open contacts (FIG. 5-3).

2. If both a high and low gas pressure switch is used, connect
their respective contacts in series, and connect them to the
terminals on the connection board (FIG. 5-3).

Variable speed system pump

If a variable speed pump is used in the primary loop, and a
0-10V signal is available from the pump speed control, this
signal can be used by the SMART SYSTEM control to anticipate
changes in the building heat load. By connecting this 0 - 10V
signal to the 0 - 10V SYS PUMP IN terminals, the boiler (or
cascade) can modulate up and down as the primary flow
increases and decreases.

Boiler pump speed output

This 0 - 10V output is available to control the speed of a variable
speed boiler pump. The SMART SYSTEM control will vary the
speed of this pump in order to maintain a minimum T across
the heat exchanger, as well as prevent high limit lockouts when
the flow in the primary loop is extremely low. Connect this
output to the 0 - 10V input on the boiler pump speed control.

Rate output

This output provides a 0 - 10V signal that is proportional to the
firing rate of the boiler. This may be used by a BMS system to
monitor the actual rate of the boiler.

ModBus

When the optional ModBus interface module is installed, the
RS-485 ModBus cable is connected to these terminals. Use
shielded, 2-wire twisted pair cable. If desired, the shield can
be connected to ground by installing a jumper wire between
terminals 1 and 3 on connector X5 on the optional ModBus
interface module.

3. If the TST20015 is not compatible with the indirect
tank, a tank thermostat can be used to control the
boiler. The tank thermostat should be installed per
the manufacturers instructions and wired to the DHW
Thermostat terminals on the Low Voltage Connection
Board.

29

Outdoor Knight Boiler Installation & Operation Manual

5 Field wiring

Flow switch

1. A flow switch is used to guarantee flow through the
boiler before allowing it to fire. The flow switch must be
installed at the boiler outlet.

2. Remove the jumper wire from these terminals, and
connect these terminals to the normally open contacts on
the flow switch (FIG. 5-3).

System supply sensor

1. By installing the system supply sensor into the supply
of the primary loop, the temperature of the primary
supply can be controlled. The SMART SYSTEM control
automatically detects the presence of this sensor, and
controls the boiler firing rate to maintain the system
supply temperature to the set point (if the outlet sensor
control is currently selected). If it is desired to control
the system return temperature, then program the
SMART SYSTEM control to use the inlet sensor as
the controlling sensor. See the Outdoor Knight Boiler
Service Manual for instructions on how to use the inlet
sensor as the controlling sensor. When the inlet sensor
is programmed as the controlling sensor, it is vital that
the SYSTEM SUPPLY sensor be installed. DO NOT
INSTALL THE SYSTEM SUPPLY SENSOR INTO THE
SYSTEM RETURN.

2. The TST2032 sensor provided with the boiler must be
used for the system sensor.

3. Connect these terminals to the system supply sensor
(FIG. 5-3).

Boiler management system

The United States Energy Policy and Conservation Act
requires residential heating boilers with inputs less than
300,000 Btu/hr be equipped with a control that automatically
adjusts boiler water temperature in relation to heat demand.
An external control may be connected to control the firing
rate or the set point of the boiler provided that either an
external energy management system is installed that reduces
the boiler water temperature as the heating load decreases,
the boiler is not used for any space heating, or the boiler is
part of a modular or multiple boiler system having a total
input of 300,000 Btu/hr or greater.

1. An external control may be connected to control either
the firing rate or the set point of the boiler. If the external
control uses a set of contacts to enable the boiler, connect
the contacts to the Heat/Loop Demand 1 terminals.
Otherwise, the SMART SYSTEM control will be enabled
by the 0-10V signal.

2. Make sure the (-) terminal is connected to the (-) or
common output terminal of the external control, and
the 0 - 10 Vdc terminal is connected to the 0 - 10 Vdc
terminal of the external control. Make sure the (-)
voltage is not below ground.

Runtime contacts

The SMART SYSTEM control closes a set of dry contacts
whenever the burner is running. This is typically used by
Building Management Systems to verify that the boiler is

responding to a call for heat.

Alarm contacts

The SMART SYSTEM control closes another set of contacts
whenever the boiler is locked out or the power is turned off.
This can be used to turn on an alarm, or signal a Building
Management System that the boiler is down.

Wiring of the cascade

When wiring the boilers for Cascade operation, select one
boiler as the Leader boiler. The remaining boilers will be
designated as Members. See page 38 “Configuration of the
Cascade” for a detailed explanation of this procedure.

Connect the system supply sensor and outdoor air sensor (if
used) to the Leader boiler. For the Cascade system to work
properly the system supply sensor must be installed. The
location of the system supply sensor should be downstream
of the boiler connections in the main system loop (FIG.’s 3-5,
3-7, and 3-9). The system supply sensor should be wired to the
Low Voltage Connection Board at the terminals marked for
the system sensor (see FIG. 5-3). The Leader control will use
the water temperature at the system supply sensor to control
the operation of the Cascade.

The outdoor air sensor should be wired to the Low Voltage
Connection Board at the terminals marked for the outdoor air
sensor (FIG. 5-3). The Leader control will calculate the water
temperature set point based on the programmed reset curve
parameters.

If a Thermostat, Zone Control enable output, or Building
Management System enable output is available, it should
be wired to the Low Voltage Connection Board on the
Leader boiler at the terminals marked for one of the heat/
loop demands 1-3 (FIG. 5-3). If the boilers are to run
continuously, connect a jumper wire between the R and W
terminals for the heat/loop demand input. This will initiate a
call for heat on the Cascade.

Communication between the Leader boiler and the Member
boilers is accomplished by using shielded, 2-wire twisted pair
communication cable. Connect one of the twisted pair wires
to Cascade terminal A on each of the Low Voltage Connection
boards, and the other wire of the twisted pair to Cascade
terminal B on each of the Low Voltage Connection Boards.
Connect the shield wires to one of the shield terminals on
the Low Voltage Connection Boards (FIG. 5-3). If more than
two boilers are on the Cascade, daisy chain the wiring from
the Cascade terminals on the second boiler to the Cascade
terminals on the third boiler, then from the third to the forth,
and so on. The connections between boilers can be made in
any order, regardless of the addresses of the boilers. Try to
keep each cable as short as possible.

30

5 Field wiring (continued)

Figure 5-3 Low Voltage Field Wiring Connections

SYSTEM SUPPLY SENSOR

OUTDOOR SENSOR

TO

A

NEXT

BOILER

B

TANK SENSOR

Outdoor Knight Boiler Installation & Operation Manual

IMG00127

NOTE:

CONNECTION BOARD SPLIT FOR

ILLUSTRATION PURPOSES

A

B

FROM

BOILER

PREVIOUS

SHIELD

SHIELD

LOW WATER

CUTOFF

SPEED

CONTROL

SYSTEM PUMP

PUMP

BOILER

B
A

SYSTEM

BUILDING

MANAGEMENT

NEEDED

WIRE AS

COM

FLOW SWITCH

NO

TANK THERMOSTAT

ROOM THERMOSTAT 3

ROOM THERMOSTAT 2

ROOM THERMOSTAT 1

31

6 Condensate disposal

Outdoor Knight Boiler Installation & Operation Manual

Condensate drain

1. This boiler is a high efficiency appliance that produces
condensate.

2. The side of the boiler has a 1/2 inch PVC union for
connection of a 1/2 inch PVC pipe (FIG. 6-1).

3. Slope condensate tubing down and away from the
boiler into a drain or condensate neutralizing filter.
Condensate from the outdoor boiler will be slightly acidic
(typically with a pH from 3 to 5). Install a neutralizing
filter if required by local codes.

A Neutralizer Kit (FIG. 6-1) is available from the factory

(Kit 3087).

4. Install the 1/2 inch PVC tee assembly (shipped with the
unit) as shown in FIG. 6-1.

5. Leave the top of the 1/2 inch tee OPEN. This is needed as
a vacuum break.

6. Do not expose condensate line to freezing temperatures.
Precautions should be taken to protect the condensate
management and disposal system during extended
periods of outdoor temperatures below 32°F.

NOTICE

Use materials approved by the authority
having jurisdiction. In the absence of
other authority, PVC and CPVC pipe
must comply with ASTM D1785 or D2845.
Cement and primer must comply with
ASME D2564 or F493.

NOTICE

To allow for proper drainage on large
horizontal runs, a second line vent may
be required and tubing size may need to
increase to 1 inch.

The condensate line must remain
unobstructed, allowing free flow of
condensate. If condensate is allowed to
freeze in the line or if the line is obstructed
in any other manner, condensate can exit
from the boiler tee, resulting in potential
water damage to property.

8. A condensate removal pump is required if the boiler is
below the drain. When installing a condensate pump,
select one approved for use with condensing boilers and
furnaces. The pump should have an overflow switch to
prevent property damage from condensate spillage. The
switch should be wired in series with the blocked drain
switch inside the boiler (see FIG. 7-1 on page 34).

7. Use only plastic tubing or piping as a condensate drain
line (FIG. 6-1).

Figure 6-1 Condensate Disposal

1/2" PVC TEE ASSEMBLY

(FACTORY SUPPLIED)

1/2" PVC UNION
(FACTORY SUPPLIED)

32

NEUTRALIZER KIT

FLOOR DRAIN OR
DRAIN PAN

IMG00387

7 Start-up

Outdoor Knight Boiler Installation & Operation Manual

Check/control water chemistry

 CAUTION

Hardness less than 7 grains

1. Consult local water treatment companies for hard water
areas (above 7 grains hardness).

Chlorine concentration less than 200 ppm

1. Do not fill boiler or operate with water containing
chlorine in excess of 200 ppm.

2. Filling with chlorinated fresh water should be acceptable
since drinking water chlorine levels are much lower.

3. Do not use the boiler to directly heat swimming pool or
spa water.

Test/replace freeze protection fluid

1. For systems using freeze protection fluids, follow fluid
manufacturer’s instructions.

2. Freeze protection fluid must be replaced periodically due
to degradation of inhibitors over time. Follow all fluid
manufacturer’s instructions.

Do not use petroleum-based cleaning or
sealing compounds in the boiler system.
Damage to elastomer seals and gaskets
in the system could occur, resulting in
substantial property damage.

Freeze protection (when used)

1. Determine freeze protection fluid quantity using

system water content, following fluid manufacturer’s
instructions. Boiler water content is listed on page 7.
Remember to include expansion tank water content.

2. Local codes may require a backflow preventer or actual

disconnect from city water supply.

3. When using freeze protection fluid with automatic fill,

install a water meter to monitor water makeup. Freeze
protection fluid may leak before the water begins to
leak, causing concentration to drop, reducing the freeze
protection level.

4. The freeze protection set points may be lowered when

freeze protection fluid is used (see the Outdoor Knight
Service Manual).

Fill and test water system

1. Fill system only after ensuring the water meets the
requirements of this manual.

2. Close manual and automatic air vents and boiler drain
valve.

3. Fill to correct system pressure. Correct pressure will vary
with each application.

a. The minimum cold water fill pressure for a
residential system is 12 psi.

b. Pressure will rise when boiler is turned on and

system water temperature increases.

4. At initial fill and during boiler startup and testing, check
system thoroughly for any leaks. Repair all leaks before
proceeding further.

 WARNING

Eliminate all system leaks. Continual
fresh makeup water will reduce boiler life.
Minerals can build up in the heat exchanger,
reducing heat transfer, overheating the heat
exchanger, and causing heat exchanger
failure.

Purge air from water system

1. Purge air from system:

a. Connect a hose to the purge valve (see purge/drain

valves, in piping diagrams on pages 17 through 23).
Route the hose to an area where water can drain and
be seen.

b. Close the boiler or system isolation valve between

the purge valve and fill connection to the system.

c. Close zone isolation valves.
d. Open quick-fill valve on cold water makeup line.
e. Open purge valve.
f. One zone at a time, open the isolation valves. Allow

water to run through the zone, pushing out the air.
Run until no noticeable air flow is present. Close the
zone isolation valves and proceed with the next zone.
Follow this procedure until all zones are purged.

g. Close the quick-fill water valve and purge valve and

remove the hose. Open all isolation valves. Watch
that system pressure rises to correct cold-fill
pressure.

h. After the system has operated for a while, eliminate

any residual air by using the manual air vents located
throughout the system.

i. If purge valves are not installed in the system, open

the manual air vents in the system one at a time,
beginning with the lowest floor. Close the vent when
water squirts out. Repeat with remaining vents.

2. Open automatic air vent (diaphragm-type or bladder-type
expansion tank systems only) one turn.

3. Open other vents:

a. Starting on the lowest floor, open air vents one at a

time until water squirts out.

b. Repeat with remaining vents.

4. Refill to correct pressure.

33

7 Start-up

Outdoor Knight Boiler Installation & Operation Manual

Check for gas leaks

 WARNING

 WARNING

Figure 7-1 Condensate Trap

Before starting the boiler, and during
initial operation, smell near the floor and
around the boiler for gas odorant or any
unusual odor. Remove the top access
cover and smell the interior of the boiler
enclosure. Do not proceed with startup
if there is any indication of a gas leak.
Use an approved leak detection solution.
Repair any leaks at once.

DO NOT adjust gas valve outlet pressure.
The gas valve is factory set for the correct
outlet pressure. This setting is suitable
for natural gas and propane, requiring
no field adjustment. Attempting to
alter the gas valve outlet pressure could
result in damage to the valve, causing
potential severe personal injury, death, or
substantial property damage.

RETAINING

SCREW

 WARNING

Propane boilers only – Your propane
supplier mixes an odorant with the propane
to make its presence detectable. In some
instances, the odorant can fade, and the
gas may no longer have an odor. Before
startup (and periodically thereafter), have
the propane supplier verify the correct
odorant level in the gas.

Check thermostat circuit(s)

1. Disconnect the two external wires connected to each
of the heat/loop demand terminals on the connection
board.

2. Connect a voltmeter across these two incoming wires.
Close each thermostat, zone valve, and relay in the
external circuit one at a time and check the voltmeter
reading across the incoming wires.

3. There should NEVER be a voltage reading.

4. If a voltage does occur under any condition, check and
correct the external wiring. (This is a common problem
when using 3-wire zone valves.)

CONDENSATE FROM

HEAT EXCHANGER

2” PVC CAP WITH

BLOCKED DRAIN SWITCH

PVC TEE ASSEMBLY

(FACTORY SUPPLIED)

TO FLOOR

DRAIN

5. Once the external thermostat circuit wiring is checked and
corrected if necessary, reconnect the external thermostat
circuit wires to the connection board.

Inspect/fill condensate system

Inspect/check condensate lines and fittings

1. Inspect the condensate drain line, condensate PVC
fittings and condensate trap.

Fill condensate trap with water

1. Remove the PVC cap retaining screw from the PVC cap
(FIG. 7-1).

2. Remove the 2 inch PVC cap with the switch located at the
top of the trap (FIG. 7-1).

3. Fill with fresh water until the water begins to pour out of
the drain.

4. Replace the cap. Press the cap onto the trap until the cap
makes contact with the drain.

5. Replace the retaining screw.

34

 WARNING

The condensate trap (FIG. 7-1) must be
filled with water during all times of boiler
operation to avoid flue gas emission from
the condensate drain line. Failure to fill
the trap could result in severe personal
injury or death.

Outdoor Knight Boiler Installation & Operation Manual

7 Start-up (continued)

Final checks before starting the boiler

 Check gas piping

 Read the Outdoor Knight Boiler Service Manual to

familiarize yourself with SMART SYSTEM control
module operation. Read this manual, page 36 for proper
steps to start boiler.

 Verify the boiler and system are full of water and all

system components are correctly set for operation.

 Verify the preparation procedures of Section 7, pages 33

and 34 have been completed.

 Fill the vent condensate trap with water (removing the

retaining screw in order to remove the 2 inch PVC cap
with the switch located at the top of the trap). Replace
the cap. Press the cap onto the trap until the cap makes
contact with the drain. Replace the retaining screw.

 Verify electrical connections are correct and securely

attached.

 Verify air opening and vent opening are free of

obstruction.

Start the boiler

1. Read and follow the Operating instructions in FIG. 7-2,
page 36.

If boiler does not start correctly

1. Check for loose connections, blown fuse or service switch
off?

2. Is boiler water temperature above 200°F?

3. Is thermostat set below the controlling sensor
temperature?

1. Check around the boiler for gas odor following the
procedure on page 24 of this manual (connecting gas supply
piping).

 WARNING

 Propane boilers – verify conversion

1. Verify propane conversion has been completed per the
Propane Conversion instructions.

 WARNING

 WARNING

If you discover evidence of any gas leak,
shut down the boiler at once. Find the
leak source with a bubble test and repair
immediately. Do not start the boiler again
until corrected. Failure to comply could
result in severe personal injury, death, or
substantial property damage.

DO NOT adjust gas valve outlet pressure.
The gas valve is factory-set for the correct
outlet pressure. This setting is suitable
for natural gas and propane, requiring
no field adjustment. Attempting to alter
the gas valve outlet pressure could result
in damage to the valve, causing potential
severe personal injury, death, or substantial
property damage.

Outdoor boilers are typically shipped ready
to fire on natural gas. Check boiler rating
plate to determine which fuel the boiler is set
for. If set to natural gas, it may be converted
to LP by installing an orifice (see page 11).
In order to operate on LP gas, an orifice
MUST BE installed. Failure to comply could
result in severe personal injury, death, or
substantial property damage.

Check flame and combustion

4. Is gas turned on at meter or boiler?

5. Is incoming gas pressure less than 4 inches w.c.?

If none of the above corrects the problem, refer to the
Troubleshooting Section of the Outdoor Knight Boiler
Service Manual.

Check system and boiler

 Check water piping

1. Check system piping for leaks. If found, shut down
the boiler and repair immediately. (See WARNINGS
on pages 33 and 34 (startup) regarding failure to repair
leaks.)

2. Vent any remaining air from the system using manual
vents. Air in the system will interfere with circulation
and cause heat distribution problems and noise.

1. Turn the main power off to the boiler by placing the “On/
Off” switch in the OFF position.

2. Remove the flue temperature sensor from the flue pipe
connection. NOTE: Combustion measurements will be
made at this point.

3. Turn the main power on to the boiler by placing the “On/
Off” switch in the ON position.

35

7 Start-up

Figure 7-2 Operating Instructions

Outdoor Knight Boiler Installation & Operation Manual

36

Outdoor Knight Boiler Installation & Operation Manual

7 Start-up (continued)

Check flame and combustion (continued) Set space heating operation

NOTICE

4. Place the boiler into the active position by pressing the
RIGHT SELECT [ON] key (FIG. 8-1, page 45).

5. Locate the pinhole button below the RESET button on
the display board (FIG. 8-1). Insert a thin wire (such as
a paper clip) into the hole and press the button once and
hold for 5 seconds to place the boiler into Service Mode.
In Service Mode the boiler will fire at ignition speed and
will then modulate up to full fire.

6. Insert the probe from a combustion analyzer into the flue
outlet opening.

7. Once the boiler has modulated up to full fire, measure the
combustion. The values should be in the range listed in
Table 7A below. The CO levels should be less than 150
ppm for a properly installed unit.

If the combustion is not within the specified range,

reference the Troubleshooting Section of the Outdoor
Knight Boiler Service Manual for possible causes and
corrective actions.

Table 7A Flue Products Chart

Natural Gas Propane

CO

2

8.0% - 10% 3.0% - 6.5% 9.0% - 11% 4.1% - 6.9%

8. Once the combustion analysis is complete, test the safety

shutoff device by turning the manual shutoff switch to
the OFF position and ensuring that the boiler shuts
down and registers an alarm. Turn the manual shutoff
switch to the ON position and reset the control.

9. Turn the main power off to the boiler.

10. Place the boiler back into normal operation.

Please note that the brackets ([]) denote
screen status.

O

2

CO

2

O

2

Determine controlling sensor

For space heating systems, the temperature control can be
based on one of three sensors; the inlet, outlet, or system
supply sensor. The SMART SYSTEM control is programmed
at the factory to control the temperature of the outlet
sensor. The control will automatically switch to the system
supply sensor once it is connected. If it is desired to base
the temperature control on the inlet sensor, the appropriate
parameter must be changed in the control. See the Outdoor
Knight Boiler Service Manual for a detailed explanation of
this procedure.

Verify space heat circulator mode

The Space Heating Mode controls both the system pump
(if connected), and the boiler pump. When the SMART
SYSTEM control receives a space heating call for heat, it turns
on the system pump. If the boiler is not heating an indirect
DHW (Domestic Hot Water) tank, and the set point is not
met, it also turns on the boiler pump. After the space heating
call for heat ends, the system pump continues to run for a
short period of time. The system pump can be programmed
to run continuously, except during outdoor shutdown. If
the boiler pump was running, it continues to run for a short
period of time as well. These pump delays are factory set to
30 seconds. If different delays are desired, the appropriate
parameters in the control must be changed. See the Outdoor
Knight Boiler Service Manual for a detailed explanation of
this procedure.

Adjust set point temperature(s)

NOTICE

The NAVIGATION dial may be used during normal
operation to adjust the space heating and tank set point
temperatures.

1. From the Status Screen press the NAVIGATION dial.

2. Turn the NAVIGATION dial counterclockwise to select
the appropriate set point.

3. Press the NAVIGATION dial to adjust the temperature.

4. Once the desired temperature is displayed, press the
RIGHT SELECT [SAVE] key.

5. If necessary repeat Steps 3 and 4 to make adjustments to
additional set points.

6. Press the RIGHT SELECT [HOME[ key to upload the
changes.

7. If the RIGHT SELECT [SAVE] key is not pressed, the
new settings will be discarded.

Please note that the brackets ([]) denote
screen status.

37

Outdoor Knight Boiler Installation & Operation Manual

7 Start-up

Set domestic hot water (DHW) operation

Verify DHW mode

There are two (2) modes of operation for DHW. In Normal
Mode, when a DHW demand begins, the control will start
the DHW pump, turn off the boiler pump (if running), and
modulate to bring the outlet temperature to the DHW boiler
set point. The maximum firing rate may be limited in this
mode if desired.

In Zone Mode it is assumed that the indirect DHW tank is
piped as a zone on the primary loop. When a DHW demand
begins, the control will turn on the DHW pump output, and
raise the system temperature set point to the DHW boiler set
point (if higher). The boiler pump will be turned on. The
system pump may be forced on, forced off, or not changed,
depending on the System Pump Mode selected (reference the
Outdoor Knight Service Manual for details). In this mode,
any low temperature zones (such as radiant heating) may
need additional controls to limit the water temperature sent
to those zones.

Set DHW boiler target temperature

When in the DHW Mode, the control will modulate to
maintain the boiler outlet temperature or system supply
temperature to a set point. This set point is set at the factory
to 180°F. If a different set point is desired, the appropriate
parameter in the control must be changed. See the Outdoor
Knight Boiler Service Manual for a detailed explanation of
this procedure.

Set maximum DHW fan speed

If the rated input of the indirect tank is less than the
maximum output of the boiler, change the maximum DHW
fan speed setting to limit the boiler output accordingly, see
the Outdoor Knight Boiler Service Manual for a detailed
explanation of this procedure.

Set clock

NOTICE

The SMART SYSTEM control has a built-in clock that it
uses for its night setback feature and for logging events. This
clock must be set when the boiler is installed, and anytime
the boiler has been powered off for more than 4 hours. Use
the following procedure to set the clock:

1. Press and hold the LEFT SELECT [MENU] key for at
least 5 seconds.

2. The display changes to read [PASSWORD],
with four (4) zeros below it.

3. Press the RIGHT SELECT [SAVE] key.

4. The display will then show a menu with the time and
date and temperature unit.

5. Press the NAVIGATION dial twice.

6. Turn the NAVIGATION dial to adjust the hours. Press
the NAVIGATION dial.

7. Turn the NAVIGATION dial to adjust the minutes. Press
the NAVIGATION dial.

38

Please note that the brackets ([]) denote
screen status.

8. Turn the NAVIGATION dial to adjust the month. Press the
NAVIGATION dial.

9. Turn the NAVIGATION dial to adjust the date. Press the
NAVIGATION dial.

10. Turn the NAVIGATION dial to adjust the year. Press the
RIGHT SELECT [SAVE] key.

11. Press the RIGHT SELECT [HOME] key.

NOTICE

The clock is automatically updated whenever a PC is connected
and the Win Pro-Installer program is started.

Configuration of the cascade

NOTICE

When installed in a Cascade system, the individual controls
must be programmed for cascade operation. This is
accomplished by accessing the control parameters.

Press the [MENU] key for at least five (5) seconds. Input
the Installer code as described in the Outdoor Knight Boiler
Service Manual. Once the control parameters have been
accessed, use the NAVIGATION dial to select the Control
Mode parameters. Press the NAVIGATION dial to access
these parameters.

Rotate the NAVIGATION dial to select the parameter
“Cascade Address”. Press the NAVIGATION dial to access
this parameter. Each appliance in the Cascade system must
be programmed with its own address. The boiler designated
as the Leader will have an address of 0. The remaining boilers
in the Cascade will be Members and have addresses from 1

- 7. Rotate the NAVIGATION dial to select the appropriate
address. Press the RIGHT SELECT [SAVE] key.

Press the RIGHT SELECT [HOME] key to upload the address
into the control. Repeat this procedure for all boilers in the
Cascade, designating the Leader control and the Member
controls.

The internal clock does not adjust for
Daylight Savings Time and therefore, will
require a manual adjustment.

Please note that the brackets ([]) denote
screen status.

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information

General

How the boiler operates

The outdoor boiler uses an advanced stainless steel heat
exchanger and electronic control module that allows fully
condensing operation. The blower pulls in air and pushes flue
products out of the boiler through the heat exchanger and flue
piping. The control module regulates blower speed to control
the boiler firing rate. The gas valve senses the amount of air
flowing into the boiler and allows only the right amount of gas
to flow.

How the control module operates

The SMART SYSTEM control module receives inputs from
boiler sensors and external devices. The control module
activates and controls the blower and gas valve to regulate heat
input and switches the boiler, Domestic Hot Water (DHW),
and system pumps on and off as needed. The user programs
the module to meet system needs by adjusting control
parameters. These parameters set operating temperatures
and boiler operating modes. Boiler operation can be based on
boiler outlet water temperature, boiler inlet water temperature,
system temperature, a 0-10V signal or ModBus, depending on
the parameter settings.

Control inputs and outputs

Room thermostat

There are three (3) heat/loop demand connections available on
this control. These inputs tell the boiler to provide water for
space heating. Each demand connection has its own set point
and outdoor air reset curve. When multiple demands have a
call for heat the control will give priority to the demand with
the highest set point.

Example: Assume that both heat/loop demand
1 and heat/loop demand 2 have a call for heat.
Demand 1 has a set point of 110°F. Demand 2 has a set point
of 140°F. The boiler will regulate the system temperature to
140°F until Demand 2 has been satisfied. Once Demand 2 has
been satisfied the boiler will provide 110°F water to the system.

 CAUTION

SMART SYSTEM Multi-temp loop control

The outdoor boiler is capable of producing up to three (3) set
point temperatures to meet different space heating demands.
This device controls the temperatures of up to three (3)
separate loops, based on the settings for the three (3) heat/loop
demands (reference Lochinvar kit RLY30086).

0 - 10V input (set point or power)

The outdoor boiler can be controlled by a Building
Management System (BMS) provided that either an external
energy management system is installed that reduces the boiler
water temperature as the heating load decreases, the boiler
is not used for any space heating, or the boiler is part of a
modular or multiple boiler system having a total input of
300,000 Btu/hr or greater.

When multiple temperature loops are
used, mixing valves are required for the
protection of any low temperature loops.

The control can be configured by the installer to use a 0 - 10
Vdc signal to either control set point or firing rate.

The outdoor boiler can also be programmed to accept a call for
heat from a 0 - 10V signal, reference the Outdoor Knight Boiler
Service Manual for a detailed explanation of this procedure.

DHW priority

The SMART SYSTEM control allows the connection of a DHW
thermostat or tank sensor to the low voltage connection board.
When a tank sensor is connected, the DHW thermostat input
is ignored. When a boiler is programmed for DHW Normal
Mode, the maximum firing rate can be limited to match the
input rating of the indirect tank coil.

DHW / space heating (SH) cycling

If a DHW call for heat is received while a space heating call is
in progress, and the DHW is in Normal Mode, the control will
start the DHW pump and shut the boiler pump off. The system
pump will remain on. For stand-alone boilers, if the space
heating call is still active while the DHW call is in operation,
the control will wait for 30 minutes (time adjustable by
installer) then it will switch back to the space heating demand.
There is a timer to switch from space heating to DHW and a
timer to switch from DHW to space heating. The control will
switch back and forth until one of the heat demands end.

Programmable controlling sensor

The control module is programmed to use the outlet sensor
as the control sensor by default. If a system supply sensor
is connected, the control automatically uses it as the control
sensor. For stand-alone boilers, the control sensor can be
changed by the installer to the inlet sensor. If the inlet sensor
is chosen as the controlling sensor, it is recommended that the
system supply sensor be installed in the system supply in order
to provide the best control of the inlet temperature.

Anti-cycling

After the burner turns off, the control will delay the next
burner cycle for a set time period (time is adjustable by the
installer). The time delay will be bypassed if the inlet water
temperature drops too far during the delay.

Boiler and system pump control

The boiler pump will run whenever the burner is firing, unless
the DHW is programmed for Normal Mode and the boiler
is heating the DHW tank. The boiler pump will run during
Freeze Protection Mode as well. It will continue to run for a
short time after the burner turns off or the Freeze Protection
Mode ends.

The system pump will run whenever there is a space heating
call for heat, or the boiler goes into Freeze Protection Mode. It
may be programmed to run during a DHW call for heat when
the DHW is programmed for Zone Mode. It will continue
to run for a short time after the end of the heat demand
or the Freeze Protection Mode. The system pump can be
programmed to run continuously if desired, except during
outdoor shutdown and/or a DHW call for heat.

39

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information

Temperature control

Modulation

The outdoor boiler is capable of modulating its firing rate
from a minimum of 20% to a maximum of 100%. The
firing rate is dictated by the call for heat (i.e., space heating
or domestic hot water), the heating load, ramp delay (if
enabled), and various other temperature limitations.

Ramp delay

For systems with lower flow, the SMART SYSTEM can limit
the firing rate (when enabled) when a space heating call for
heat starts, or when switching from a DHW call for heat to a
space heating call for heat. There are six (6) limits that can be
programmed, as well as six (6) time intervals corresponding
to each limit. The sixth limit will also limit the firing rate for
the rest of the call for heat.

Gradient limiting

If during operation of the boiler the outlet water temperature
is rising too quickly, the control will reduce the firing rate to
its lowest setting.

Outdoor air reset

With the outdoor air sensor connected, the control module
will calculate the set points of the three (3) space heating
demands based on the programmed reset curves. The
installer can change the slope of the reset curves by several
adjustable parameters. The user can limit the maximum set
point for the system using the space heating set points.

Boost function

If outdoor air reset is active, and any space heating demand
has been active continuously for a set period of time (time
adjustable by installer) and there has been no DHW demands,
the control will increase the set point of that demand
by a fixed number of degrees (adjustable by installer).
This process will continue until the space heating demand
ends, the set point reaches the programmed set point or a
maximum of 20 increases has occurred. Once the system
heat demand is satisfied, the set point will revert to the value
determined by the reset curve.

Night setback

The controller may be programmed to reduce the space
heating and DHW set points during certain times each week.
Seven different start and stop times may be programmed
for the space heating setback and seven start and stop times
for the DHW setback. Any night setback event scheduled
within the next seven (7) days can be temporarily bypassed
if desired.

Flame current support

To prevent nuisance shutdowns when the boiler is firing at
minimum rates, the control will increase the firing rate when
the flame signal drops too low.

Protection features

Outlet temperature, flue temperature, and
temperature rise limiting

The outlet temperature is monitored by the boiler outlet
temperature sensor. When the outlet temperature exceeds
185°F, the unit will reduce the fan speed. If the outlet water
temperature exceeds 195°F the control will shut the unit
down until it cools off.

The control module monitors the flue temperature by a
sensor located in the flue exhaust. If the flue temperature
exceeds 215°F the control will reduce the maximum fan
speed. If the flue temperature exceeds 240°F the control will
shut the unit down. The unit will restart automatically once
the flue temperature drops 25°F and the minimum off time
has expired.

The control monitors the temperature difference between
the inlet and the outlet sensor. If this difference exceeds
55°F the control will reduce the maximum fan speed. If
the temperature difference exceeds 60°F the control will
shut the unit down. The unit will restart automatically once
the temperature difference has dropped below 55°F and the
minimum off time has expired.

Freeze protection

DO NOT install the boiler where it is likely to freeze.

The following integral feature of the SMART SYSTEM
control module provides some protection for the boiler only

-- not for the system.

• The SMART SYSTEM control module provides
freeze-up protection as follows when the boiler
water temperature drops below 45°F:

• Below 45°F, the boiler and system pumps operate
constantly.

• Below 37°F, the boiler turns on.

• Boiler and pumps turn off if boiler water
temperature rises above 45°F.

• Lower temperatures may be programmed for
systems with anti-freeze solutions.

NOTICE

 CAUTION

When system return temperatures
are maintained below the dew point,
condensation will form on the inside of
the boiler jacket causing some internal
sheet metal components to rust.

This feature of the SMART SYSTEM
control module does not eliminate the
possibility of freezing. The installation
must still use recognized design,
installation and maintenance practice to
prevent freeze potential for the boiler and
system.

40

8 Operating information (continued)

Monitor external limits

Connections are provided on the connection board for
external limits such as a flow switch, low water cutoff and
gas pressure switches. The SMART SYSTEM will shut off the
burner and inhibit relighting whenever any of these external
limits open.

Run-time and alarm outputs

The boiler provides dry contacts for indicating when the
boiler is running, and when it is unable to operate.

Run-time and cycle counting

The control uses two timers to monitor the total hours of
burner operation. One timer monitors the time the boiler is
firing in the Space Heating Mode. The other timer monitors
the time the boiler is firing in the DHW Mode.

The control uses two (2) ignition counters to monitor the
amount of boiler cycles. The first counter counts all ignitions
of the control. The second counter counts only ignition
attempts that have failed.

Service reminder

The control can be programmed for service reminder
notification. This notification will become active when
either a set time frame has expired, or a set amount of
running hours or cycles has expired (all adjustable by the
installer). The display will show a Maintenance Required
screen. The installer's name and phone number can be
programmed into the control. This information will appear
on the Maintenance Required screen. The service reminder
notification can be reset or disabled by the installer.

The time dependent feature has been disabled by the
manufacturer. To enable this feature change the parameter
to the desired time interval, reference the Outdoor Knight
Service Manual for details regarding parameters.

Error logging

The control will hold in memory the last 10 lockouts as
well as the last 10 blockings. The date and time of the
occurrence will be recorded as well. Only the 10 most current
occurrences of each will be held in memory.

Boiler temperature regulation

Operating temperature (target)

The SMART SYSTEM control module senses water
temperature and regulates boiler firing and firing rate to
achieve a target temperature. The target temperature can be
set between 32°F and 190°F.

• Target temperature is calculated as described in the
“Outdoor Reset Operation” section, when the
outdoor sensor is connected.

• If the outdoor sensor is not connected, the target
temperature is fixed at SH (1 - 3) set points. An
outdoor sensor fault will remain on the display
screen until the outdoor sensor is reconnected.

High limit operations

The outdoor boiler is equipped with adjustable automatic
reset and manual reset high limits. The automatic reset high
limit has a maximum set point of 200°F and the manual reset
high limit has a maximum set point of 210°F.

Outdoor Knight Boiler Installation & Operation Manual

When the outlet temperature exceeds 200°F, the automatic
high limit action occurs. The boiler shuts down until the outlet
water temperature cools below 190°F, and a 60 second timer
has expired. If the outlet temperature continues to increase, the
manual reset high limit action will occur at 210°F.

High limit test procedure

NOTICE

1. Turn ON the main power to the boiler by placing the
ON/OFF switch in the ON position.

2. From the Status Screen, press the NAVIGATION dial to
access the Set Points Screen.

3. Press the LEFT SELECT (LIMITS) key.

4. Select the manual reset high limit (MRHL) by rotating
the NAVIGATION dial counterclockwise, then press
the NAVIGATION dial.

5. Decrease the set point of the MRHL to below the current
outlet temperature (or to its minimum setting, whichever
is higher) by turning the NAVIGATION dial
counterclockwise.

6. Press the RIGHT SELECT [SAVE] key.

7. Press the RIGHT SELECT [HOME] key. The new
parameter will upload to the control.

8. If the current outlet temperature is above the new MRHL
set point, the MRHL will function causing boiler lockout.
If this occurs, skip to Step 11.

9. If the current outlet temperature is below the new MRHL
set point, locate the pinhole (SERVICE button) below the
RESET button on the display board. Insert a thin probe
(such as a paper clip) into the hole and press the button
continuously for five (5) seconds to place the boiler into
Service Mode. In Service Mode, the boiler will fire at
ignition speed and will then modulate up to full fire.

10. Once the outlet temperature rises up to the MRHL set
point, the MRHL will function, causing the boiler to shut
down and lock out.

11. Repeat Steps 2, 3 and 4.

12. Set the MRHL to the appropriate set point by turning the
NAVIGATION dial clockwise.

13. Repeat Steps 6 and 7.

14. Press the RESET button to clear the lockout.

15. If needed, press the RIGHT SELECT [STOP] key to exit
Service Mode.

Low water cutoff protection

1. The SMART SYSTEM control module uses temperature
sensing of both supply and return areas of the heat
exchanger. If the flow rate is too low or the outlet
temperature too high, the control module modulates and
shuts the boiler down. This ensures boiler shutdown in the
event of low water or low flow conditions.

2. Some codes and jurisdiction may accept these integral
features of the control in lieu of requiring an additional
limit control or low water cutoff. Consult local jurisdiction
to determine. A low water cutoff is available from the
factory (WTR30024).

Please note that the brackets ([]) denote
screen status.

41

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information

Outdoor reset operation

Target temperature with outdoor reset

This feature improves the system's efficiency by decreasing set
point as the outdoor temperature warms up. Energy Efficiency
Standards require the use of a control that automatically adjusts
set point in relation to heat demand. In the absence of an
external energy management system, this feature MUST BE
used.

See the Outdoor Knight Boiler Service Manual to change the
settings.

Reset curve

The reset curve looks at outdoor air temperature and adjusts
the set point in relation to heat demand.

Cascade

When multiple boilers are installed, they can be wired together
in a cascade sequence. A maximum of eight boilers can be
controlled from a single control. In this application one boiler
would be designated as the Leader control and all others would
be designated as Member controls. The Leader control can
be programmed to use Lead/Lag or Efficiency Optimization
control methods.

Once the Leader boiler receives a call for heat from a room
thermostat, BMS, or ModBus, the control will determine what
the set point will be. If outdoor air reset is desired, connect
the outdoor air sensor to the terminals on the Low Voltage
Connection Board on the Leader boiler. The set point will be
calculated based on the programmed reset curve parameters.
See the Outdoor Knight Boiler Service Manual to program the
reset curve. If outdoor air reset is not desired, do not connect
the outdoor air sensor. A fixed temperature set point can be
programmed into the control. See page 37 of this manual to
program the set point.

If the water temperature at the system supply sensor is less than
the set point + the turn-off offset - the off-on differential, then
the control will initiate a call for heat on the Cascade (see the
Outdoor Knight Boiler Service Manual for an explanation of
the offset and differential). The Leader will energize the lead
boiler on the Cascade. For a new startup this will be the Leader
boiler.

Sequence of the cascade

To equalize the run time of all boilers on the Cascade, the
firing sequence will automatically be changed at set intervals.

During the first 24 hours of operation, the sequence will
change every hour. After that, the sequence will change every
24 hours. The switching on/off sequence will be as follows:

TIME SWITCHING ON SEQUENCE

Start L-M1-M2-M3-M4-M5-M6-M7

1 hour M1-M2-M3-M4-M5-M6-M7-L

2 hours M2-M3-M4-M5-M6-M7-L-M1

If a boiler locks out or is used to heat an indirect DHW tank,
it will automatically be given the lowest priority for the rest
of that 24 hour period.

DHW, Night Setback, and Ramp Delay operation
with cascade

For Normal Mode DHW operation any boiler(s) in the
Cascade can be selected to provide heat for a DHW call.
Select a boiler to be designated as the DHW boiler. Connect
the DHW thermostat or sensor to the terminals on the Low
Voltage Connection Board marked for the corresponding
device. When the boiler receives a DHW call, the Leader
control will take that boiler out of the Cascade sequence. If
another boiler is available, the Leader will start it up to take
its place.

The DHW boiler will adjust its set point to the programmed
DHW boiler set point and will adjust its firing rate to maintain
this. Once the DHW call has been satisfied, the Leader control
will place that boiler back into the Cascade sequence.

Switching of the boiler between DHW operation and SH
operation when there is a call for both does not occur in
Cascade Mode.

When DHW is programmed for Zone Mode, connect the
DHW thermostat or tank sensor to the Leader boiler. When
a DHW call is received, the Leader will modulate the entire
Cascade to bring the system supply temperature up to the
DHW boiler set point.

42

Night Setback operation of the boilers within the Cascade is
available. Programming of the Night Setback will be done
through the Leader boiler. Refer to the Outdoor Knight Boiler
Service Manual for information regarding Night Setback.

Ramp Delay operation of the boilers as described in the
Outdoor Knight Boiler Service Manual is available when the
boilers are part of a Cascade system.

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information (continued)

Sequence of operation

OPERATION DISPLAY

1. Upon a call for heat, the gas pressure switch(es) must be closed.

2. Once the gas pressure switch(es) are closed, the control turns
on the appropriate pumps (system and boiler pumps for space
heating, DHW pump for DHW). The flow switch and/or LWCO
must close.

3. The air pressure switch and blocked drain switch must close.

4. The control starts the prepurge cycle by initiating the blower.

5. The control starts the trial for ignition by firing the spark electrode

and opening the gas valve.

6. If flame is not detected after the sparking ends, the control will

perform a post-purge, then start another prepurge cycle and try to
light the burner again. The control will perform a total of 4
attempts before locking out.

7. If flame is detected, it holds the firing rate steady for a few
seconds to let the flame stabilize, then it begins to modulate the
firing rate based on a set point or some other command (such
as a 0-10V BMS signal).

43

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information

Sequence of operation (continued)

OPERATION DISPLAY

8. If the space heating call for heat is active, and the tank thermostat
or sensor starts a DHW call for heat, the boiler will switch to the
DHW mode. If programmed for normal DHW operation (not as a
zone), the DHW pump will turn on first, then the boiler pump will
turn off 2 seconds later. This will divert the boiler’s outlet water
from the heating system and send it to the tank coil instead. The
control will then modulate to maintain the outlet temperature to
the DHW boiler set point.

9. If the boiler is not part of a Cascade, and both the space heating
and DHW calls for heat remain active long enough, the boiler will
switch back and forth between the two heating modes until one of
them is satisfied.

10. Once both calls for heat are satisfied, the control will turn off the
burner. The blower will continue to run during the
postpurge period.

11. Any pumps that are running will continue to run for their respective
pump delay times before turning off, unless programmed to
remain on continuously. A 60 second anti-cycle period will start,
which will delay any new call for heat until it times out.

12. In Standby, ready to start a new cycle.

44

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information (continued)

Outdoor Knight boiler control module

Use the control panel (FIG. 8-1) to set temperatures, operating conditions, and monitor boiler operation.

Figure 8-1 Control Panel

NAVIGATION DIAL

(PRESS OR TURN)

The information on the bottom of the display shows the functions of the two SELECT keys (on either corner), and the
NAVIGATION dial (in the center):

MENU = Left SELECT Key
SETPOINTS = NAVIGATION Dial - Pressing Down
SHDN = Right SELECT Key

Access modes

User

The user can adjust space heating and tank target temperatures
by pressing the NAVIGATION dial when “SETPOINTS” is
flashing at the bottom of the display. The date and time, and
the temperature units can also be changed (see page 38).

Installer

Most parameters are available only to the installer, accessible
by entering the installer password, see the Outdoor Knight
Boiler Service Manual.

Saving parameters (reference the Parameter Table in

the Outdoor Knight Boiler Service Manual)

NOTICE

To save parameters and exit programming:

Press the RIGHT SELECT [SAVE] key and then press the
RIGHT SELECT [HOME] key.

To enter a parameter and continue programming:

Press the RIGHT SELECT [SAVE] key 1 time to return to the
parameter listings; press again to return to the menu listings.
Remember to press the RIGHT SELECT [HOME] key when
finished programming in order to save the changes made.

See the Outdoor Knight Boiler Service Manual for a detailed
description of parameters and access modes.

Please note that the brackets ([]) denote
screen status.

45

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information

Figure 8-2 Status Display Screen

A

(BOILER

STATUS)

C

(OPERATIONAL
INFORMATION)

D

(LEFT SELECT

KEY)

E

(NAVIGATION DIAL)

Status Display Screens

Section Display Description

STANDBY

START The unit has begun a burn cycle and is checking all safety circuits.

PREPURGE The unit has initiated a prepurge period on a call for heat.

The unit has not received a call for heat from a remote thermostat nor
has it received a call for heat from a DHW thermostat.

B

(CALL FOR

HEAT)

F

(RIGHT SELECT KEY)

A

(Boiler Status

Bar)

B

(Call for Heat

Indicators)

IGNITION The unit has begun a spark period to ignite the main burner.

The unit has fired and is running at the displayed percentage.

POSTPURGE

SHUTDOWN The unit has been placed in the OFF position.

BLOCKED

%

The call for heat has been satisfied and the unit runs the fan for an
additional postpurge period to clear the combustion chamber and
vent system of residual flue products.

The controlled temperature has exceeded its set point and its offset.

The unit has detected a condition that has temporarily interrupted
the current call for heat.

Heat/Loop Demand 1 has a call for heat.

Heat/Loop Demand 2 has a call for heat.

Heat/Loop Demand 3 has a call for heat.

The tank thermostat or sensor has a call for heat.

Indicates which Heat/Loop Demand has priority.

The unit is being controlled by a 0 - 10V BMS signal.

The unit is supplying heat while in Cascade Mode.

46

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information (continued)

Status Display Screens (cont’d)

Section Display Description

SYSTEM: The temperature read by the system supply sensor (if connected).

TANK: The temperature read by the tank sensor (if connected).

OUTDOOR: The temperature read by the outdoor sensor.

INLET TEMP: The temperature read at the inlet to the heat exchanger.

OUTLET TEMP: The temperature read at the outlet of the heat exchanger.

C

(Operational

Information)

DELTA T:

FLUE TEMP: The temperature read by the flue sensor.

FLAME CURRENT: The current measured by the flame sense circuit.

FAN SPEED: The speed of the combustion blower.

BOILER PUMP: The status of the boiler pump output.

SYSTEM PUMP: The status of the system pump output.

DHW PUMP: The status of the DHW pump output.

BMS VOLTAGE: The voltage received from a BMS system.

BLR PUMP OUTPUT: The speed signal sent to a variable speed boiler pump in percent.

SYS PUMP INPUT: The speed signal received from a variable speed system pump control.

RATE OUTPUT: A 0 - 10V signal indicating the firing rate of the boiler.

SH RUN HOURS: The total hours of operation in the Space Heating Mode.

SH CYCLES: The total burner cycles in the Space Heating Mode.

The temperature difference between the inlet and the outlet of the
heat exchanger.

DHW RUN HOURS: The total hours of operation in the DHW Mode.

DHW CYCLES: The total burner cycles in the DHW Mode.

LAST 10 FAULTS NO: The last 10 lockouts.

NIGHT SETBACK Shows the next Night Setback trigger (if active).

47

Outdoor Knight Boiler Installation & Operation Manual

8 Operating information

Status Display Screens (cont’d)

Section Display Description

MENU

EXIT Press the LEFT SELECT key to exit the current screen or setting.

Press and hold the LEFT SELECT key for 5 seconds to enter the Menu
Screen.

D

(LEFT SELECT

key function)

E

(NAVIGATION

Dial Function)

YES

LIMITS

HOME

SKIP

Press the LEFT SELECT key to confirm that the boiler needs to
shutdown.

Press the LEFT SELECT key to enter the screen that allows you to
adjust the limit settings.

Press the LEFT SELECT key to return to the Status Screen and upload
parameter changes.

Press the LEFT SELECT key when in the Night Setback Screen to
access the Night Setback Skip Screen.

Turning the NAVIGATION dial will select the next or previous Status
Screen.

Pressing the NAVIGATION dial will show the next fault, NSB (Night
Setback) trigger, or ramp delay setting.

Pressing the NAVIGATION dial will select the setting indicated by
the cursor.

Pressing the NAVIGATION dial will display the Set Points Screen.

Turning the NAVIGATION dial will move the cursor up or down.

Turning the NAVIGATION dial will increase or decrease the current
setting.

SHDN Press the RIGHT SELECT key to turn the boiler OFF.

ON Press the RIGHT SELECT key to turn the boiler ON.

F

(RIGHT SELECT

key function)

48

NO Press the RIGHT SELECT key to cancel the shutdown operation.

SAVE Press the RIGHT SELECT key to save the current change.

HOME

Press the RIGHT SELECT key to return to the Status Screen and
upload parameter changes.

Outdoor Knight Boiler Installation & Operation Manual

9 Maintenance

Maintenance and annual startup

Table 9A Service and Maintenance Schedules

Service technician

(see the following pages for instructions)

General:

• Address reported problems

• Inspect interior; clean and vacuum if
necessary;

• Clean condensate trap and fill with fresh
water

• Check for leaks (water, gas, flue,
condensate)

• Verify flue and air openings in good
condition and free of obstruction

• Check system water pressure/system
piping/expansion tank

• Check control settings

• Check ignition and flame sense
electrodes (sand off any deposits; clean
and reposition)

Owner maintenance

(see the Outdoor Knight User’s Information Manual

for instructions)

• Check boiler area

• Check pressure / temperature
gauge

Daily

• Check air and vent termination
screens

• Check relief valve

Monthly

• Check condensate drain system

• Check wiring and connections

ANNUAL START-UP

• Perform start-up checkout and
performance verification per Section 7
of this manual.

• Flame inspection (stable, uniform)

• Flame signal (at least 10 microamps at
high fire)

• Clean the heat exchanger if flue
temperature is more than 54°F above
return water temperature.

If combustion or performance
indicate need:

• Clean heat exchanger

• Remove and clean burner using
compressed air only

• Clean the blower wheel

Periodically

Every

6 months

End

of season

months

• Test low water cutoff (if used)

• Reset button (low water cutoff)

• Check boiler piping (gas and
water) for leaks

• Operate relief valve

• Shut boiler down (unless boiler
used for domestic hot water)

49

9 Maintenance

Outdoor Knight Boiler Installation & Operation Manual

 WARNING

Follow the service and maintenance procedures given throughout this manual and in component literature
shipped with the boiler. Failure to perform the service and maintenance could result in damage to the boiler
or system. Failure to follow the directions in this manual and component literature could result in severe
personal injury, death, or substantial property damage.

 WARNING

The boiler should be inspected annually only by a qualified service technician. In addition, the maintenance
and care of the boiler designated in Table 9A and explained on the following pages must be performed to
assure maximum boiler efficiency and reliability. Failure to service and maintain the boiler and system could
result in equipment failure.

 WARNING

Electrical shock hazard – Turn off power to the boiler before any service operation on the boiler except as
noted otherwise in this instruction manual. Failure to turn off electrical power could result in electrical shock,
causing severe personal injury or death.

Address reported problems

1. Inspect any problems reported by the owner and correct
before proceeding.

Inspect boiler area

1. Verify that boiler area is free of any combustible materials,
gasoline and other flammable vapors and liquids.

2. Verify that air intake area is free of any of the contaminants
listed in Section 1 of this manual. If any of these are
present in the boiler intake air vicinity, they must be
removed.

Figure 9-1 Condensate Trap

RETAINING

SCREW

2” PVC CAP WITH

BLOCKED DRAIN SWITCH

PVC TEE ASSEMBLY

(FACTORY SUPPLIED)

Inspect boiler interior

1. Remove the front access cover and inspect the interior of
the boiler.

2. Vacuum any sediment from inside the boiler and
components. Remove any obstructions.

Clean condensate trap

1. Inspect the condensate drain line, condensate PVC
fittings, and condensate trap.

2. Remove the PVC cap retaining screw from the PVC cap
(FIG. 9-1).

3. Remove the 2 inch PVC cap with the switch located at the
top of the trap (FIG. 9-1).

4. Remove any sediment in the trap.

5. Fill with fresh water until the water begins to pour out of
the drain.

6. Replace the cap. Press the cap onto the trap until the cap
makes contact with the drain.

7. Replace the retaining screw.

CONDENSATE FROM

HEAT EXCHANGER

 WARNING

The condensate trap must be filled with
water during all times of boiler operation

TO FLOOR

DRAIN

to avoid flue gas emission from the
condensate drain line. Failure to fill the
trap could result in severe personal injury
or death.

Check all piping for leaks

 WARNING

1. Inspect all water and gas piping and verify to be leak free.

2. Look for signs of leaking lines and correct any problems
found.

3. Check gas line using the procedure found in Section 4

- Gas Connections.

Eliminate all system or boiler leaks.
Continual fresh makeup water will
reduce boiler life. Minerals can build
up in sections, reducing heat transfer,
overheating heat exchanger, and causing
heat exchanger failure. Leaking water may
also cause severe property damage.

50

9 Maintenance (continued)

Outdoor Knight Boiler Installation & Operation Manual

Flue vent system and air piping

1. Visually inspect the entire flue gas venting system and air
piping for blockage, deterioration or leakage. Repair any
joints that show signs of leakage.

2. Verify that boiler vent discharge and air intake are clean
and free of obstructions.

 WARNING

Failure to inspect for the above conditions
and have them repaired can result in
severe personal injury or death.

Check water system

1. Verify all system components are correctly installed and

operational.

2. Check the cold fill pressure for the system. Verify it is

correct (must be a minimum of 12 psi).

3. Watch the system pressure as the boiler heats up (during

testing) to ensure pressure does not rise too high.
Excessive pressure rise indicates expansion tank sizing or
performance problem.

4. Inspect automatic air vents and air separators. Remove

air vent caps and briefly press push valve to flush vent.
Replace caps. Make sure vents do not leak. Replace any
leaking vents.

Check expansion tank

1. Expansion tanks provide space for water to move in

and out as the heating system water expands due to
temperature increase or contracts as the water cools.
Tanks may be open, closed or diaphragm or bladder
type. See Section 3 - Hydronic Piping for suggested best
location of expansion tanks and air eliminators.

Check boiler relief valve

1. Inspect the relief valve and lift the lever to verify flow.

Before operating any relief valve, ensure that it is piped
with its discharge in a safe area to avoid severe scald
potential. Read Section 3 - Hydronic Piping before
proceeding further.

 WARNING

 WARNING

2. After following the above warning directions, if the relief
valve weeps or will not seat properly, replace the relief
valve. Ensure that the reason for relief valve weeping is
the valve and not over-pressurization of the system due
to expansion tank waterlogging or undersizing.

Safety relief valves should be re-inspected
AT LEAST ONCE EVERY THREE YEARS,
by a licensed plumbing contractor or
authorized inspection agency, to ensure
that the product has not been affected by
corrosive water conditions and to ensure
that the valve and discharge line have not
been altered or tampered with illegally.
Certain naturally occurring conditions
may corrode the valve or its components
over time, rendering the valve inoperative.
Such conditions are not detectable unless
the valve and its components are physically
removed and inspected. This inspection
must only be conducted by a plumbing
contractor or authorized inspection
agency – not by the owner. Failure to
re-inspect the boiler relief valve as directed
could result in unsafe pressure buildup,
which can result in severe personal injury,
death, or substantial property damage.

Following installation, the valve lever
must be operated AT LEAST ONCE
A YEAR to ensure that waterways are
clear. Certain naturally occurring
mineral deposits may adhere to the valve,
rendering it inoperative. When manually
operating the lever, water will discharge
and precautions must be taken to avoid
contact with hot water and to avoid water
damage. Before operating lever, check
to see that a discharge line is connected
to this valve directing the flow of hot
water from the valve to a proper place of
disposal. Otherwise severe personal injury
may result. If no water flows, valve is
inoperative. Shut down the boiler until a
new relief valve has been installed.

51

9 Maintenance

Outdoor Knight Boiler Installation & Operation Manual

Inspect ignition and flame sense
electrodes

1. Remove the ignition and flame sense electrodes from the
boiler heat exchanger access cover.

2. Remove any deposits accumulated on the ignition/flame
sense electrode using sandpaper. If the electrodes cannot
be cleaned satisfactorily, replace with new ones.

3. Replace ignition/flame sense electrode, making sure
gasket is in good condition and correctly positioned.

Check ignition ground wiring

1. Inspect boiler ground wire from the heat exchanger
access cover to ground terminal strip.

2. Verify all wiring is in good condition and securely
attached.

3. Check ground continuity of wiring using continuity
meter.

4. Replace ground wires if ground continuity is not
satisfactory.

Check burner flame

1. Inspect flame through observation window.

2. If the flame is unsatisfactory at either high fire or low fire,
turn off boiler and allow boiler to cool down. Remove the
burner and clean it thoroughly using a vacuum cleaner or
compressed air. Do not use compressed air to clean burner
if performed inside a building.

3. Remove the burner, reference FIG. 9-2 below.

4. When replacing the burner, ensure gasket is in good
condition and positioned correctly (FIG. 9-2).

Figure 9-2 Burner Assembly

AIR / GAS ARM

Check all boiler wiring

1. Inspect all boiler wiring, making sure wires are in good
condition and securely attached.

Check control settings

1. Set the SMART SYSTEM control module display to
Parameter Mode and check all settings. See Section 1 of
Outdoor Knight Boiler Service Manual. Adjust settings
if necessary. See Section 1 of the Outdoor Knight Boiler
Service Manual for adjustment procedures.

2. Check settings of external limit controls (if any) and
adjust if necessary.

Perform start-up and checks

1. Start boiler and perform checks and tests specified in
Section 7 - Start-up.

2. Verify cold fill pressure is correct and that operating
pressure does not go too high.

INSULATION

HEAT EXCHANGER
ACCESS DOOR

BURNER

GASKET

SCREWS
(QTY. 5)

IMG00447

Check flame signal

1. At high fire the flame signal shown on the display should be
at least 10 microamps.

2. A lower flame signal may indicate a fouled or damaged
flame sense electrode. If cleaning the flame sense electrode
does not improve, ground wiring is in good condition, and
ground continuity is satisfactory, replace the flame sense
electrode.

3. See Section 3 - Troubleshooting of the Outdoor Knight
Boiler Service Manual for other procedures to deal with
low flame signal.

52

9 Maintenance (continued)

Outdoor Knight Boiler Installation & Operation Manual

Review with owner

1. Review the Outdoor Knight Boiler User’s Information
Manual with the owner.

2. Emphasize the need to perform the maintenance
schedule specified in the Outdoor Knight Boiler User’s
Information Manual (and in this manual as well).

3. Remind the owner of the need to call a licensed contractor
should the boiler or system exhibit any unusual behavior.

4. Remind the owner to follow the proper shutdown
procedure and to schedule an annual start-up at the
beginning of the next heating season.

Cleaning boiler heat exchanger

For recommended materials; including brush, appropriate
extension(s), refractory cover, and detailed instructions see
Table 9B - Heat Exchanger Cleaning Kits.

1. Shut down boiler:

• Follow the “To Turn Off Gas to Appliance” instructions
for the boiler in Section 7 - Startup.

• Do not drain the boiler unless it will be exposed to
freezing temperatures. If using freeze prevention fluid
in system, do not drain.

2. Allow time for the boiler to cool to ambient temperature

if it has been firing.

3. Remove the nuts securing the heat exchanger access

cover to the heat exchanger and set aside.

4. Remove the heat exchanger access cover, burner, and

gas/air arm assembly.

11. Close isolation valves on piping to isolate boiler from
system. Attach a hose to the boiler drain and flush boiler
thoroughly with clean water by using purging valves to
allow water to flow through the water make-up line to the
boiler.

12. Perform start-up and check-out procedures in the Check
Flame and Combustion - Section 7 - Startup on pages 35
and 37 of this manual.

13. Replace the access cover and restore boiler to operation.

Table 9B Heat Exchanger Cleaning Kits

Model

151

-

286

 CAUTION

Figure 9-3 Rope Gasket - Heat Exchanger Door

Kit

Number

KIT30063

* Do NOT use a metal brush. Only use
the kit provided brush or an equivalent
replacement nylon brush.

Part

Number

CTN20005 Rear Refractory Cover

MSC20083* Nylon 4" Wheel Brush*

MSC20084 3mm Allen Wrench
MSC20086 1/4" x 24" Drill Extension

Component
Description

ROPE GASKET

 WARNING

5. Remove the condensate hose from the heat exchanger
end. Connect a field supplied 3/4" diameter hose to
a drain pan. Using field supplied means, cover the
refractory in the back of the combustion chamber of the
heat exchanger.

6. Use a vacuum cleaner to remove any accumulation on the
boiler heating surfaces. Do not use any solvent.

7. Brush the heat exchanger while dry using a nylon bristle
brush. Caution: DO NOT use a metal brush. Re-vacuum
the heat exchanger.

8. Finish cleaning using a clean cloth dampened with warm
water. Rinse out debris with a low pressure water supply.

9. Allow the heat exchanger to thoroughly dry.

10. Remove the field supplied rear refractory cover from the
back of the combustion chamber of the heat exchanger
and reassemble.

The boiler contains ceramic fiber
materials. Use care when handling these
materials per instructions in the Service
Manual. Failure to comply could result in
severe personal injury.

CAUTION: IF GASKET IS DAMAGED

DO NOT REUSE, THE HEAT EXCHANGER DOOR

MUST BE REPLACED.

NOTICE

Rope gasket is intended for sealing combustion
(FIG. 9-3). If damaged DO NOT reuse, the
heat exchanger door must be replaced. Consult
factory for replacement heat exchanger door
(kit WTR3080).

Oiled bearing circulators

1. The circulator shipped with the outdoor boiler is water­lubricated. No oiling is required.

2. Check other circulators in the system. Oil any circulators
requiring oil, following circulator manufacturer’s
instructions. Over-oiling will damage the circulator.

3. Replace the boiler front access cover.

53

10 Diagrams

Figure 10-1 Ladder Diagram

120VAC

TERMINAL STRIP

120V SUPPLY "L"

ON / OFF

KB ONLY

SWITCH

PC INTERFACE

BELL

ALARM

SWITCH

SILENCING

CONTACTS

RUN-TIME

CONTACTS

SYSTEM
SENSOR

OUTDOOR

SENSOR

TANK

SENSOR

SHIELD

A

CASCADE

B

SHIELD

BMS

+

IN

-

+

SYS PUMP

IN

-

+

BLR PUMP

OUT

-

+

RATE

OUT

-

SHIELD

A

MODBUS

B

SHIELD

1

2

6

13

ALARM

X4-3

CN5-5

X1-6

S6

S5

S4

0-10V

0-10V

0-10V

0-10V

X5-9

KB 801

3.5A

ONLY

CONNECTION

JUNCTION BOX

INTEGRATED CONTROL

F2

3.15A

F1

5A

SYSTEM PUMP

BOILER PUMP

F3

.8A

120 VAC

24 VAC

CN7-3

CN7-1

19

17

15

13

10

S2

INLET

SENSOR

S1a

OPERATING

SENSOR

S1b

HIGH LIMIT

SENSOR

S3a

FLUE

SENSOR

S3b

FLUE

SENSOR

BOARD

1

2

3

4

21
22

23

24

26

27

29

30

31

32

33

34

35

36

37

38

39

40

41

CN8-1

42

CN8-2

43

CN8-3 X6-3

44

RELAY

RELAY

DHW PUMP

RELAY

24V DC
SUPPLY

HEAT/LOOP

HEAT/LOOP

HEAT/LOOP

THERMOSTAT

LOW GAS
PRESSURE

SWITCH

RIBBON CABLE

CN5-1

CN5-8

CN5-2

CN5-9

CN6

CN6

CN6

CN6

CN6

CN6

CN6

CN6

CN6

CN6

CN6

CN6

CN6

CN6

CN6

X6-1

X6-2

Outdoor Knight Boiler Installation & Operation Manual

GROUND

NEUTRAL

TERMINAL STRIP
120V SUPPLY "N"

12

12

5

6

7

8

BLOCKED

DRAIN SWITCH

BLOWER

3

CN5-14 X4-8

CN5-10

CN5-7 X4-1

CN5-13

CN5-6

CN5-12

CN5-11

CN5-3

CN5-4 X4-4

X5-2

X5-10

X5-11

X2-2

X2-1

1

2

4

5

TR2

X1-7

FLAME ROD

INTEGRATED

X4-12

X4-9

X4-2

X4-10

X4-11

X4-5

GAS VALVE

X5-7

X5-16

X5-8

X5-15

BOX DEPICTS

OPTIONAL ITEMS

LOW VOLTAGE
120 VAC
HIGH VOLTAGE

CONTROL

RELAY

LADDER DIAGRAM

LBL20148 REV D

LWCO

24 VAC

DEMAND

DEMAND

DEMAND

TANK

M
O
D
B
U
S

X1-1

X5-1

1

2

3

HIGH GAS

PRESSURE

SWITCH

X5-6

X5-4

X5-12

X5-5

X5-13

X5-14

X4-7

X4-14

X4-6

X4-13

X6

X6

X6

X6

X6

X6

X6

X6

X6

X6

X6

X6

X6

X6

X6

X4-1

X4-2

X4-3

SYSTEM

PUMP "L"

X1-2

BOILER

PUMP "L"

X1-4

DHW

PUMP "L"

X1-3

TERMINAL

STRIP

CONNECTION BOARD

CN7-4

CN7-2

20

18

16

14

9

9

INTEGRATED

CONTROL

X7

X9-2

X9-1

X9-3

GND

SYSTEM

PUMP "N"

GND

SYSTEM

PUMP

BOILER

PUMP "N"

GND

BOILER

PUMP

DHW

PUMP "N"

TERMINAL

STRIP

DHW

PUMP

FLOW

SWITCH

11

LOUVER

RELAY COIL

24VAC

LOUVER

PROVING SWITCH

KB 286 ONLY

O-TEMP HEX SW

AIR PRESSURE

SWITCH

GAS VALVE

BLOWER

SPARK

ROD

CAUTION HIGH VOLTAGE SPARK LEAD

NOTES:

1. Where possible, switches are shown wit hout utilities (gas, water or
electricity) connected to the unit. As such, actual switch states may
vary from those shown on diagrams depending upon whether utilities
are connected or a fault condition is present.

2. See wiring diagram for additional notes.

54

10 Diagrams (continued)

Figure 10-2 Wiring Diagram

Outdoor Knight Boiler Installation & Operation Manual

CONNECTION BOARD

ALARM

CONTACTS

RUN-TIME

CONTACTS

24 VAC LOUVER

RELAY COIL

BELL JUMPER

ALARM BELL

SILENCING SWIT CH

Notes:

1. All wiring must be installed in accordance with: local, state,

2. If any original equipment wire as supplied with the appliance
minimum of 105°C. Exceptions: Replacement high voltage spark lead
or ribbon cables can lead to operational problems which could re

3. Actual connector block locations may vary from those shown on
diagrams to troubleshoot unit.

LOUVER

PROVING SWITCH

GAS PRESSURE

SWITCH

FLOW

SWITCH

TANK
THERMOSTAT
HEAT/LOOP

DEMAND

HEAT/LOOP

DEMAND

HEAT/LOOP

DEMAND

SYSTEM
SENSOR

OUTDOOR

SENSOR

TANK

SENSOR

SHIELD

SHIELD

BMS

SYS PUMP

BLR PUMP

OUT

RATE

OUT

SHIELD

MODBUS

OPTION

SHIELD

LOW

WATER

CUT-OFF

SHIELD

JUMPER

A

B

+

IN

-

+

IN

-

+

-

+

-

A

B

CASCADE

GROUNDING

3
2
1

0-10V

0-10V

0-10V

0-10V

24 VAC

COM

1
2
3
4
5
6
7
8
9

10

11
12
13
14
15
16
17
18
19
20

21
22
23
24
25
26
27
28
29
30
31
32

33
34
35
36
37
38
39
40
41
42
43
44

CN7-1
CN7-2
CN7-3
CN7-4

MODBUS BOARD

X5-1
X5-2

MTR-01

provincial and national code requirements per either N.E.C. in USA or C.S.A. in Canada.

must be replaced, it must be replaced with wire having same wire gauge (AWG) and rated for a

sult in non-repairable damage to the integrated controller or o

diagrams. Refer to actual components for proper connector blo

LOW VOLTAGE
120 VAC
HIGH VOLTAGE

INTEGRATED

CONTROL

X-7

BK

CN5-1
CN5-8
CN5-2
CN5-9
CN5-3
CN5-10
CN5-11
CN5-4
CN5-5
CN5-14
CN5-12
CN5-6
CN5-13
CN5-7

CN6

CN8-1

CN8-2

CN8-3

BL

R

G

X6-3

X6-2

X6-1

X6-4

X4-1
X4-2
X4-3
X4-4

X1-1
X1-2
X1-3

and ribbon cables must be purchased from the factory. Use

X4-7

BK

X4-14

BK

X4-6

BK

X4-13

BK

X4-5

BK

X4-12

BK

X4-11

BK

X4-4

BK

X4-3

BK

X4-8

BK

X4-10

BK

X4-2

BK

X4-9

BK

X4-1

X6

O

X9-1

GY

X9-2
X9-3

G

X9-4

BK

W

G

BOX DEPICTS

OPTIONAL ITEMS

BOX DEPICTS

DUAL SENSOR

SINGLE HOUSING

X1-3

OR

BR

X1-4

X1-2

PR

X1-6

BK

X1-5

W

X1-8

G

X1-1

R

R

X5-7

T

X5-16

W

X5-8

BK

X5-15

Y

X5-9

X5-1

BL

O

X5-2

BLOCKED DRAIN SWITCH

P

X5-10

X5-11

O/BK

X5-4

R/BK

X5-12

GY

X5-6

P/BK

X5-5

W/BK

X5-13

PR

X5-14

Y

X2-2

BK

Y

X2-1

X1-7

W/R

TR2

ther components.

JUNCTION

BOX

L

N

W

L

N

W

L

N

W

KB ONLY

ON/OFF
SWITCH

R

1

W

2G3

L
N

TRANSFORMER

BLOWER

1 2 3 4

5

AIR PRESSURE SWITCH

-T

OPERATING SENSOR S1a

-T

HIGH LIMIT SENSOR S1b

-T

INLET SENSOR S2

-T

FLUE SENSOR S3a

-T

FLUE SENSOR S3b

GAS VALVE
@24VAC

FLAME SENSOR
SPARK

ROD

G

HIGH VOLTAGE SPARK LEADCAUTION

of a non-approved spark lead

ck locations when using

KB 286 ONLY

O-TEMP HEX SW

BOX DEPICTS

OPTIONAL

ITEMS

G

G

G

L

120V

GND

SUPPLY

N

WIRING DIAGRAM

LBL20127 REV E

DHW
PUMP

BOILER
PUMP

SYSTEM
PUMP

55

Revision Notes: Revision A (ECO C11234) initial release.
Revision B (ECO #C11235) reflects updates made to the freezing

conditions warnings.
Revision C (ECO #C11736) reflects changes made to the ratings page

(page 7).

OKB-I-O Rev C

11/12