Whirlpool EDP-EDN User Manual [en, fr]

Installation, Operation and Maintenance Instructions

P.O. Box 310 
Lynnfield, MA 01940 
Phone: [phone] 
Fax: [phone]

For sales, parts and service, call 781-961-1660

Installation,
Operation and
Maintenance
Instructions for

Endurance

EBP Series Modulating Combination Boiler

(natural or propane gas)

EDP Series Modulating Hydronic Boiler

(natural or propane gas)

EDN Series Modulating Boiler, non ferrous

(natural or propane gas)

FOR YOUR SAFETY: This product must be installed and serviced by a professional service technician,
qualified in hot water boiler installation and maintenance. Improper installation and/or operation could
create carbon monoxide gas in flue gases which could cause serious injury, property damage, or death.
Improper installation and/or operation will void the warranty.

If the information in this manual is not

W ARNING

followed exactly , a fire or explosion may
result causing property damage, personal
injury or loss of life.

Do not store or use gasoline or other
flammable vapors and liquids in the vicinity
of this or any other appliance.

WHA T TO DO IF YOU SMELL GAS

• Do not try to light any appliance.

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

• Immediately call your gas supplier from a
nearby 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 gas
supplier .

Assurez-vous de bien suivres les instructions
données dans cette notice pour réduire au
minimum le risque d’incendie ou d’explosion ou
pour éviter tout dommage matériel, toute
blessure ou la mort.

Ne pas entreposer ni utiliser d’essence ni
d’autres vapeurs ou liquides inflammables dans
le voisinage de cet appareil ou de tout autre
appareil.

QUE F AIRE SI VOUS SENTEZ UNE ODEUR DE GAZ:

• Ne pas tenter d’allumer d’appareils.

• Ne touchez à aucun interrupteur. Ne pas vous
servir des téléphones dansle bâtiment où vous
vous trouvez.

• Appelez immédiatement votre fournisseur de
gaz depuis un voisin. Suivez les instructions
du fournisseur.

• Si vous ne pouvez rejoindre le fournisseur de
gaz, appelez le sservice des incendies.

L’installation et l’entretien doivent être assurés p a r
un installateur ou un service d’entretien qualifié ou
par le fournisseur de gaz.

AVERTISSEMENT

30-418D

Page 2

LAARS HEATING SYSTEMS

TABLE OF CONTENTS

SECTION 1.
General Information

1A. Introduction................................................... 3

1B. Codes and Standards ................................... 3

1C. Unpacking the Appliance.............................. 4

1D. Locating the Appliance.................................. 4

1E. Clearances ................................................... 4

SECTION 2.
Venting Options

2A. Direct Vent Kits............................................. 4

2B. Installing Direct Vent Kits.............................. 4

2C. Locating the Vent on an Outside Wall...........4

2D. Stainless Steel Single Pipe Horizontal

and Vertical Vents.........................................7

2E. Air Source for Combustion

(when not direct vented) ............................... 7

2F. Connecting Special Gas Vent

to the Appliance ............................................ 8

2G. Securing Special Gas Vent...........................8

SECTION 3.
Gas Piping

3A. Gas Piping .................................................... 8

3B. Domestic Water Piping (EBP only) ............... 9

SECTION 7.
Maintenance and Component Description

7A. Unit Pump................................................... 19

7B. Gas Valve ...................................................19

7C. Safety Limit Switch ..................................... 19

7D. Operating Control Printed Circuit

Board (PCB) ............................................... 19

7E. Igniter / Flame Sensor Assembly ................ 20

7F. Transformer ................................................ 20

7G. Blower ........................................................ 20

7H. Transfer Tank (EBP only) ........................... 20

7I. Thermostatic Union (EDP/EDN only) .......... 20

7J Cleaning the Boiler Coil ..............................20

SECTION 8.
Servicing

8A. Sequence of Operation ...............................21

8B. Trouble Shooting - Fault Codes .................. 22

8B-1. Fault Code Identification.................... 22

8B-2. Fault Correction................................. 22

8B-3. Resolving Lockouts ...........................22

Fault Trees ................................................. 23

SECTION 9.
Gas Valve Calibration

9A. Gas Valve Calibration ................................. 31

SECTION 4.
Hydronic Heat Piping

4A. Hydronic Piping........................................... 10

4B. Using in a Combined Hot Water

Heating and Chilled Water

Cooling System........................................... 12

4C. Water Quality and Treatment...................... 13

SECTION 5.
Electrical Connections

5A. Electrical Connections ................................ 13

SECTION 6.
Boiler Start-UpP

6A. Common Vent Test..................................... 17

6B. Filling the System ....................................... 18

6C. Firing Burner............................................... 18

6D. Mode and On/Off Buttons Operation .......... 19

SECTION 10.
Symptom Evaluations

10A. Delayed Ignition .......................................... 31

10B. Short Cycling .............................................. 32

10C. Noisy Operation ..........................................32

10D. Insufficient Hot Water (EBP only) ............... 32

10E. High Gas Consumption............................... 33

SECTION 11.

Parts Identification.......................................... 34

Endurance

Page 3

SECTION 1.
General Information

1A. Introduction

EBP - This appliance is a low pressure, direct

vent, hot water boiler that provides priority domestic
hot water on demand as well as hydronic space heating
system. The unit has a twenty gallon tank which holds
boiler water (and is not domestic water storage).

The boiler water is kept hot at all times to
provide immediate response to call for heat or
domestic water. Domestic water is heated by the boiler
water through a stainless steel plate heat exchanger.

EDP/EDN - This appliance is a low pressure,
direct vent, cold start hot water boiler that provides
heat for hydronic space heating.

Both appliances incorporate a circulating pump
and a bypass loop, and provide circulation for the
heating system and adequate flow for its own needs.
It may be necessary to install a system circulator to
achieve the required flow rate through the system.

Both appliances feature a forced draft, premixed
combustion system. All air for combustion is supplied
with the gas to the burner (flame holder). Both the

intake air and the gas are metered through separate
orifices before entering the combustion air blower.
The blower forces the air/fuel mixture through the
flame holder and into the combustion chamber. The
mixture is ignited from the hot surface ignitor and
burns. Hot gases are forced out between the passes of
the heat exchanger into the flue collector. Flue gases
are discharged into the outside atmosphere through the
vent terminal.

The appliance can operate with a concentric vent
system that will provide outside air for combustion.
Other venting arrangements can be provided for the
appliance to include an alternative 50 equivalent feet
maximum horizontal or condensate trapped vertical
vent.

1B. Codes and Standards

The Endurance may be a direct vent or Category
IV Boiler. All installations must be made in
accordance with:

1. The National Fuel Gas Code, ANSI Z223.1 latest

edition, or.

2. CAN/CGA B149 “Installation Codes for Gas

Burning appliances and Equipment” and with the

requirements of the local utility or other

authorities having jurisdiction. Such application

requirements take precedence over the general

instructions contained herein.
All electrical wiring is to be done in accordance with:.

1. The National Electrical Code ANSI / NFPA70

latest edition or

Figure 1. Combo Heating/Domestic Water (Model EBP).

Figure 2. Heating Unit (Model EDP/EDN).

Page 4

LAARS HEATING SYSTEMS

2. The CSA standard C22.1 “Canadian Electrical
Code - Part 1” and local codes.

All vent installations must be made in accordance with:

1. Part 7, Venting of Equipment of the National Fuel
Gas Code, ANSI 223.1 latest edition, or applicable
provisions of the local building codes or

2. CAN/CGA B149.
When required by the jurisdiction authority, the

installations must conform to the American Society of
Mechanical Engineers' Safety Code for Controls and
Safety Devices for Automatically Fired Boilers, No.
CSD-1.

1C. Unpacking the Appliance

Remove all packing and tie down materials.

Make immediate claims (to the carrier) if the
appliance and its packaging are damaged.

1D. Locating the Appliance

The appliance is designed for installation on

combustible flooring, in alcoves, basements, closets,
or utility rooms. It must not be installed on carpeting.
IF INSTALLED IN A FINISHED AREA,
PROVISION SHOULD BE MADE FOR DRAINAGE
OF ANY ACCIDENTAL SPILLAGE OR LEAKAGE.

The location for the unit should be chosen with

regard to venting dimensions, convenient access to
piping, and accessibility for service and cleaning.

The boiler shall be installed so that the gas

ignition system components are protected from water
(dripping, spraying, rain, etc.) during appliance
operation or service (circulator replacement, control
replacement, etc.).

SECTION 2.
Venting Options

2A. Direct Vent Kits

When using a direct vent kit, the appliance is a
sealed combustion unit. All of its air is drawn in from
the outside through the 5" outer pipe. Flue gases are
vented through the 3" vent pipe positioned inside the
5" intake pipe. The hot flue gases are surrounded by
the intake flow of cooler outdoor air. This vent system
may be installed through, and be in contact with,
combustible materials. Except for roof vent kit (max 7'
vertical) all venting should pitch away (down) from
unit.

2B. Installing Direct Vent Kits

The direct vent appliance is certified with a
maximum of 15 linear feet (4.6m) of vent pipe and
three sets of elbows. There are two basic vent kits
available, together with various additional elbow and
extension kits if required (see Figures 3 and 4).
Detailed installation instructions are provided in the kits.

For additional length and/or fittings, the
following components are available:

3" and 5" elbow set Part Number 2400-330

5" x 1' extensions Part Number 2400-332

5" x 2' extensions Part Number 2400-334

5" x 2' to 4' adjustable

extensions Part Number 2400-336
3" x 1' extensions Part Number 2400-338
3" x 2' extensions Part Number 2400-340
3" x 2' to 4' adjustable

extensions Part Number 2400-342

1E. Clearances

The dimension and criteria in Table 1 should be

followed when choosing the location for the unit.

2C. Locating the Vent on an Outside Wall

The center line of the vent opening must be at

least 16½" (419mm) above grade, outside, and at least
13½" (343mm) from any other building opening, such
as doors, windows, etc. Vent opening should be well
away from shrubbery or other obstructions that would

A B

AGA/CGA AGA CGA

in.
Left Side 1 25 6 152 24 610
Right Side 1 25 12 305 24 610
Top Side 1 25 14 356 24 406
Back 1 25 9 229 12 305
Front 1 25 24 610 24 610

mm

in.

mm

in.

mm

prevent free air flow to and from vent terminal. Do not
terminate vent under decks, stairways, or car ports.

NOTE: Should it be impossible to locate

opening center line 16½" (419mm) above grade, use
optional vent terminal extension (p/n 2400-278).

Vent terminals must also be at least 3' (0.9m)
above any forced air inlet located within 10' (3.0m),
and at least 7' (2.1m) above grade when located
adjacent to a public walkway, and cannot terminate in

Vent: Direct Vent 0 0 0 0
Vent: Category IV 3 76 3 76

A. Minimum clearance from combustible construction to

meet AGA/CGA requirements.

B. Recommended clearance for accessibility and venting.

Table 1. Clearances

a location where condensate or vapor may be a
nuisance, hazard, or could be a detriment to other
equipment. Vent terminals must have a minimum
clearance of 4' (1.2m) (6' (1.8m) in Canada)
horizontally from, and in no case above or below
electrical meters, gas meters, regulators, and relief
equipment unless a 4' (1.2m) horizontal distance is
maintained.

Endurance

Page 5

Figure 3. Part number 2400-500 provides all of the required venting materials for appliance installations adjacent to an
outside wall and for installation of wall mounted units. Requires minimum above unit clearance of 13" (330mm) and
provides maximum horizontal length of 24" from unit center line to outside wall face.

Figure 4. Part number 2400-326 for vent installations which require adjustable height and horizontal run. This kit
provides vertical and horizontal lengths of pipe from 2' to 3½' (0.6 to 1.1m). To adapt 2400-278 (vent terminal
extension) remove 3" screen section of telescoping piece. Companion section will directly fit extension.

Page 6

Figure 5. Part number 2400-328 provides all of the required venting materials for appliance installations that require
adjustable horizontal run, but a short vertical run. It requires minimum above unit clearance of 13" (330mm) and
provides for an adjustable horizontal run of 2' to 3-1/2' (0.6 to 1.1m).

LAARS HEATING SYSTEMS

Figure 6. Part number 2400-360 provides the required venting materials for concentric through-the-roof vents. It allows
for a vertical vent, straight off the top of the unit, from 2 to 7 feet (0.6 to 2.1m).

Endurance

Figure 7. For Appliances Certified as Direct Vent.

Figure 8. Typical vent installation with 18" or less
overhead clearance to outside.

Page 7

2D. Stainless Steel Single Pipe Horizontal

and Vertical Vents - Category IV

Stainless steel special gas Vent listed to U.L.

Standard 1738 and U.L.C. Standard 636 may be used

Minimum clearance from
combustibles (vent) 3" 76mm
Max. flue gas temp. 325°F 163°C
Max. vent pressure 1.5" WC 0.4kPa
Max. equivalent ft. of venting 3" 76mm

(any combination of horizontal diameter diameter
or vertical) 50 equiv. ft. 15.2m

Max. equivalent ft. of venting 100 equiv. ft. 30.5m

(any combination of horizontal
or vertical) 4" diameter 102mm dia.

Table 2. Appliance Venting Design Data.

to vent all models. Vent pipe and fittings are
manufactured to these standards by HeatFab, Inc.
under the trade name of Saf-T Vent
under the trade name of Z-Vent. Follow the Special
Gas Vent manufacturer's instructions regarding design,
location and assembly of the vent system.

The appliance may be vented with any number of
elbows or fittings provided that the maximum
equivalent feet of venting is not exceeded. Elbows
(90°) in the vent system shall be considered to be 5
equivalent feet (1.5m). When vented with special gas
vent, the appliance must not be common vented with
any other appliance.

For applications requiring vertical venting
through a roof, the above limitations apply. Vertical
vents greater than 7' (2.1m) in length must offset a
condensate trap tee p/n 2400-358 adjacent to the
appliance. Utilize vent cap p/n 2400-370 to terminate
vertical venting.

®

and by Z-Flex

™

Figure 9. Multiple Concentric Vent Clearances.

When appliances are used, the concentric vent
terminals must be at least 12" apart, edge-to-edge (see
Figure "term").

Do not locate the vent terminal where blockage
by snow is a possibility, or where flue products could
strike against building materials and cause
degradation. If the vent terminal location chosen is
less than 18" below an overhang, the 3" vent pipe
must extend to the outside edge of the overhang (see
Figure 6).

2E. Air Source For Combustion

(when not direct vented)

When using Category IV venting methods the
appliance draws all combustion air through its top and
from the adjacent space. When locating the appliance
in unconfined spaces in buildings, infiltration may be
adequate to provide air for combustion and ventilation.
However, in buildings of unusually tight construction,
or when locating the appliance in a confined space,
additional air should be provided and the following
guidelines must be followed.

1. If the space is in a building of unusually tight

construction, air should be obtained from

outdoors, or from spaces which freely connect

with outdoors.

2. For boilers in confined rooms, two permanent

openings shall be provided - one within 12"

(305mm) of the ceiling, and one within 12"

(305mm) of the floor of each room. Each

opening shall be at least one square inch

Page 8

Figure 10. Special Gas Vent Connection.

Figure 11. Non-Concentric Combustion Air Source.

(6.5 sq. cm) per 1,000 BTU/hr (293W) boiler
input, but not be less than 100 square inches
(645.2 sq. cm). These openings shall freely
connect with areas having adequate infiltration
from outside.

3. When all air is provided from outdoors, the
confined space shall be provided with one
opening within 12" of the ceiling. This opening
shall connect directly, or by ducts, with outdoors
or spaces (crawl or attic) that freely connect
with the outdoors, and shall have a minimum free
area of:

a. 1 sq. in. per 3000 BTU/hr (7 cm

2

/kw) of the
total input rating of all equipment located
in the enclosure, and

b. Not less than the sum of the areas of all

vent connectors in the confined space.

2F. Connecting Special Gas Vent

to the Appliance

Part number 2400-372 is used with a vent

terminal (p/n 2400-277) to secure the 3 inch special

LAARS HEATING SYSTEMS

gas vent to the flue outlet of the appliance. Heat-Fab
pipe or fittings (p/n 2400-350 or 2400-352) or the male
end of Z-Vent pipe (Z-Vent # 02 SVEPXX030) may
be installed over the flue outlet of the Appliance (see
Figure 10).

2G. Securing Special Gas Vent

Attach p/n 2400-277 with sheet metal screws to
the 5" collar on the appliance with a short piece of 5"
pipe or to the end of the 5" combustion air duct.
Attach p/n 2400-372 bracket and tighten clamp. Form
the tabs on the bracket onto the special gas vent pipe
and secure the tabs with the 3" clamp. After the clamp
has been tightened, fold the end of the tabs down over
the clamp (see Figure 10).

DO NOT use screws in any portion of the 3"
special gas vent.

When providing combustion air from another
location, the connection of the 5" duct to the appliance
must be secured with sheet metal screws.

Each 5" joint in the 5" duct must be secured with
sheet metal screws.

In this type of installation, p/n 2400-372 must be
used to secure the special gas vent at the point where it
exits the duct. The combustion air supply should be
protected from debris entering the duct with an
appliance vent terminal, p/n 2400-277, as shown in
Figure 8 or with a large mesh screen.

Follow the special gas vent manufacturer's
instructions for cleaning and sealing all parts before
assembling.

Apply ¼" bead of silicone sealer (GE108 or
Novagard 400) to the 3" flue outlet of the appliance
approximately 1" from the end.

Slide 3" inner vent pipe or 1-880 adapter, when
using outer 3" telescoping section, over the appliance
flue outlet and push down to stop (do not force pipe
beyond stop).

Apply another bead of silicone around this joint
and smooth out.

Apply ¼" bead of silicone to subsequent 3" joints.

An alternate, nonconcentric combustion air
source may be installed (as shown in Figure 11),
provided that the minimum 4" diameter combustion air
duct does not exceed 15' (4.6m). Termination should
include an air screen and be located in a qualified air
space (see Section 2E) or outside.

SECTION 3.

3A. Gas Piping

The appliance requires an inlet gas pressure of at
least 4" w.c. (1.0kPa) and no greater than 13" WC
(3.2kPa). Check with your local gas utility or supplier
for availability of this pressure range.

Refer to Table 3 to size the supply piping to
minimize pressure drop between meter or regulator
and unit.

Endurance

Page 9

Length

ft.
10
20
30
40
50
75

100
150

of Pipe

m

3

6.1

9.1

12.2

15.2

22.9

30.5

45.7

MBTU/h

1/2" 3/4" 1" 1-1/4"

MBTU/h

278
190
152
130
115

93
79
64

Additional length to be added for each tee or bend

ft

1.7

132

92
73
63

ft

1.3

kW

38.7
27

21.4

18.5

m

0.4

1. Run gas supply line in accordance with all
applicable codes.

2. Locate and install manual shutoff valves in
accordance with state and local requirements.

3. Install drip leg, ground joint union and drip cap
to trap sediment and for test gauge access.

4. Support all piping with proper hangers.

5. All threaded joints should be coated with piping
compound resistant to the action of liquefied
petroleum gas.

6. The boiler and its individual shutoff valve must
be disconnected from the gas supply piping
system during any pressure testing of that system
at test pressures in excess of ½ psig (3.5kPa).

7. The boiler must be isolated from the gas supply
piping system by closing its individual manual
shutoff valve during any pressure testing of the
gas supply piping system at test pressures equal
to or less than ½ psig (3.5kPa)

8. The boiler and its gas connection must be leak
tested before placing the boiler in operation.

9. Purge all air from gas lines.

Capacity of Pipe

Table 3.

kW

81.5

55.7

44.5

38.1

33.7

27.2

23.1

18.8

m

0.5

MBTU/h

520
350
285
245
215
175
150
120

ft

2.2

kW

152.4

102.6

83.5

71.8
63

51.3
44

35.2

m

0.7

MBTU/h

1050

730
590
500
440
360
305
250

ft

2.7

be no higher than 120°F mixed delivery
temperature or as local codes dictate.
RECOMMENDS ANTI-SCALD TEMPERING
(MIXING) VALVES (see Figure 12).

2. Connect gate or shutoff valve 13 to tempering
(mixing) valve 12 “MIX” port, and cold
water inlet.

3. Install supplied flow restrictor 14 ahead of
tempering (mixing) valve tee.

4. Connect pressure relief valve 1 (if required by
codes), maximum 150 PSI as close to the unit as
possible. No other valves or restrictions may be
installed between the Endurance and the relief
valve.

DO NOT USE A TEMPERATURE/PRESSURE
RELIEF VALVE AS THIS IS NOT A STORAGE
HOT WATER HEATER.

Note: Installations with water containing 10

or more grains of hardness, must be installed with
appropriate water treatment.

kW

307.7

213.9

172.9

146.5

128.9

105.5

89.4

73.3

m

0.8

LAARS

3B. Domestic Water Piping (EBP only)

1. Connect tempering (mixing) valve 12 “Hot” port
to hot water outlet from unit. This valve should

Figure 12. Domestic Water Piping. Figure 13. Domestic Water Piping With Storage Tank.

Page 10

Figure 14. EBP Domestic Water Piping with Recirculating Loop.

LAARS HEATING SYSTEMS

WARNING

Failure to install a hot water tempering (mixing)
valve (12) creates a scalding hazard with potential for
serious bodily injury. Some brands of tempering
(mixing) valves are not designed as anti-scald valves.

Where domestic water is supplying multiple
apartments or large whirlpool tubs, additional storage
tank may be connected as shown in Figure 13. The
bronze circulator shown must be connected to tank
aquastat and must not run continuously. If the
circulator is wired to run continuously, unit's domestic
water flow switch will keep the unit in domestic water
priority, and no water will be allowed to be sent to the
heating system.

SECTION 4.
Hydronic Heat Piping

4A. Hydronic Piping

The appliance incorporates its own circulating
pump and bypass loop and is capable of providing
flow through heating zones, in addition to what it
needs for itself. Model size 110 is capable of
providing flow for two heating zones (up to 67 feet of
¾" baseboard each), and model 175 is capable of
providing flow for four heating zones (up to 67 feet of
¾" baseboard, each).

EDP/EDN boilers installed in radiant (in floor)
systems and other low mass boilers should be provided
with a buffer/blender tank to assure a controlled
supply temperature, and to prevent short cycling. In
radiant systems utilizing 3-way tempering valves, a

bypass pipe must be installed between supply and
return piping.

1. EBP ONLY: Connect system supply to 1¼"
supply connection marked “SUPPLY”.

2. EDP/EDN ONLY: Connect 1¼" thermostatic
union to system supply connection in direction
designated with union.

3. Pipe the discharge of the relief valve, full size, to
a drain or in a manner to prevent injury in the
event of pressure relief.

4. Install an air purger in flow supply line as shown
in Figures 15, 16 or 17.

5. Install automatic float type air vent on air scoops.

6. Install a diaphragm expansion tank in boiler
outlet piping. To ensure sufficient expansion
volume for the hydronic system water, due to
heat-up and cool-down during normal operation,
a #30 or larger expansion tank must be used on
EBP combo units.

NOTE: Never install expansion tank and auto
fill valve on return.

7. If necessary, install a properly sized circulator
with optional isolation valves in supply beyond
expansion tank.

Caution

All hot water pipes must be installed with a minimum
1" (25mm) clearance from combustible materials.

8. Connect boiler feed water supply with shut off
valve to inlet connection of automatic fill valve.
Locate in boiler outlet piping.

9. If codes require, install suitable back flow
preventer between automatic fill valve and city
main.

10. The appliance may be installed in single and
multiple zone systems (using either zone valves

Endurance

Figure 15. Hydronic Piping EDP/EBP with Zone Valves.

Page 11

Figure 16. Piping, Single EDP/EBP Boiler for Multiple Temperature Systems.

Figure 17. Piping, Model “EDP/EDN” for Radiant Floor.

Page 12

Figure 18. Hydronic Piping EBP/EDP for Systems Zoned with Circulators.

LAARS HEATING SYSTEMS

Figure 19. Hydronic Piping EDP for Low-Temp and/or Multi-Temp Systems.

or zone circulators) in the same manner as any
other residential boiler.

4B. Use in a Combined Hot Water Heating

and Chilled Water Cooling System

When the appliance is used in connection with a

Caution

The EBP/EDP appliance must not be direct
connected to a heating system utilizing oxygen
permeable tubing (see warranty). Provide a water to
water heat exchanger between systems to prevent
corrosion of tank or other components. Non-toxic
heating system antifreeze may be added to the
hydronic system provided that the concentration
does not exceed 35% and the antifreeze contains an
anti foamant.

refrigeration system, it must be installed so that the
chilled medium is piped in parallel with the boiler with
appropriate valves to prevent the chilled medium from
entering it.

The boiler piping system of an appliance

connected to heating coils located in air handling units
where they may be exposed to refrigerated air
circulation must be equipped with flow control valves
or other automatic means to prevent gravity circulation
of the boiler water during the cooling cycle.

Endurance

Page 13

4C. Water Quality and Treatment

Water quality control is steadily increasing in
importance in view of the use of modern regulation
technology and the modern boiler designs used in
central heating systems.

The life of a central heating boiler can be
severely curtailed as a result of the formation of scale
deposits and/or corrosion products. The formation of
such deposits should be prevented wherever possible.

Continual water make-up is not permitted.

A suitable water treatment should be used to
prevent excessive scale deposits in the boiler and
corrosion in the system.

SECTION 5.
Electrical Connections

All electrical wiring must conform to local codes
and/or the National Electric Code or Canadian
Electrical Code, Part 1.

The unit must be electrically grounded in
accordance with the requirements of the authority
having jurisdiction or, in the absence of such
requirement, with the National Electrical Code.
ANS/NFPA No. 70 latest edition, or the CSA Standard
C22.1 “Canadian Electrical Code, Part 1.”

Single pole switches, including those of safety
control and protective devices must not be wired in a
grounded line.

All electrical connections are made in the field
wiring box which is located on the top of the appli­ance, behind the right hand side of the control pod.

NOTE: All internal electric components have
been pre-wired. No attempt should be made to connect
electric wires to any other location except the wiring
box as described below.

1. Main power: Connect a fused 120 volt supply

(15 amp) to the main power switch (see

Figure 20) (hot leg is connected directly to

switch). Neutral leg to white wire. Ground wire

can be connected to the grounding screw in the

box or on the switch.

2. For single zone installations: (If external pump is
required, e.g., because of large system pressure
drop) connect room thermostat wires to the red
and white/red wires. Connect circulator (120
volt, 5 amps maximum) between the blue wire
and the white wire (neutral) (see Figure 21).

3. Zone Valves and Thermostats: Install external 24
volt transformer of sufficient V.A. to power
combined load of zone valves. Consult zone
valve manufacturer’s instructions. Connect
circulator (120 volt, 5 amp maximum) between
the blue wire and the white wire (neutral) (see
Figure 22).

ENDURANCE

FIELD WIRING BOX

Figure 20. Single Zone With Room Thermostat (internal
pump provides system flow).

ENDURANCE

FIELD WIRING BOX

Figure 21. Single Zone with Added Circulator(s) and
Room Thermostat(s).

Figure 22. Multiple Zones Utilizing Four Wire Zone Valves with (Dry) End Switches.

Page 14

LAARS HEATING SYSTEMS

4. Multi zone/Multi-relay-circulator Installations:
Multiple circulators must not exceed 5 amps total
when connected to blue wire (see Figure 24).

NOTE: On zone valve systems such as Taco,

Automag and others which do not have isolated (dry)
contact end switches, a single pole isolating relay must
be utilized (see Figure 23).

Figure 23. Multiple Zones with Three Wire Zone Valves (Requires Isolation Relay).

NOTE: This wiring is NOT the same
as shown by valve manufacturer.

Figure 24. Multiple Zones with Circulators and Room Thermostats.

NOTE: This wiring required only for
single zone applications utilizing
clock thermostats requiring 24 volt
power supply.

Figure 25. Wiring for Single Zone Power Stealing Type Clock Thermostats That Require 24 VAC.

Endurance

Page 15

FOR YOUR SAFETY READ BEFORE OPERATING

W ARNING

If you do not follow these instructions exactly, a fire or explosion

may result, causing property damage, personal injury or loss of life.

A. This appliance does not have a pilot. It is

equipped with an ignition device which
automatically lights the burner. Do not try to light
the burner by hand.

B. BEFORE OPERATING smell all around the

appliance area for gas. Be sure to smell next to
the floor because some gas is heavier than air
and will settle on the floor.
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
neighbor's phone. Follow the gas supplier's
instructions.

OPERA TING INSTRUCTIONS

1. STOP! Read the safety information above on
this label.

2. Set the thermostat to lowest setting.

3. Turn off all electric power to the appliance.

Gas Shutoff

Valve

Combination

Gas Control

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

C. Turn off gas shutoff valve (located above the

combination gas control) so that the handle is
aligned across the gas pipe. If the handle will
not turn by hand, don't try to repair it, call a
qualified service technician. Force or attempted
repair may result in a fire or explosion.

D. Do not use this appliance if any part has been

under water. Immediately call a qualified service
technician to inspect the appliance and to
replace any part of the control system and any
gas control which has been under water.

4. This appliance is equipped with an ignition
device which automatically lights the burner.
Do not try to light the burner by hand.

5. Remove control access panel, and top front cover.

6. Turn gas shutoff valve clockwise to “off”.
Handle will be horizontal, do not force.

7. Wait five (5) minutes to clear out any gas. If you
then smell gas, STOP! Follow “B” in the safety
information above on this label. If you don't
smell gas, go to next step.

8. Turn gas shutoff valve counterclockwise to
“on”. Handle will be vertical.

9. Replace top front cover and control access panel.

10. Turn on all electric power to appliance, depress
on/off button on control panel, depress black
button on top of control panel.

11. Set thermostat to desired setting.

12. If the appliance will not operate, follow the
instructions “To Turn Off Gas To Appliance” and
call your service technician or gas supplier.

TO TURN OFF GAS TO APPLIANCE

1. Set the thermostat to lowest setting.

2. Turn off all electric power to the appliance if
service is to be performed.

3. Remove control access panel and top front
cover.

4. Turn gas shutoff valve clockwise to “off”. Do
not force.

5. Replace top front cover and control access
panel.

Page 16

LAARS HEATING SYSTEMS

PAR MESURE DE PRUDENCE, LISEZ CE QUI SUIT AVANT DE

F AIRE FONCTIONNER L ’APP AREIL

MISE EN GARDE

Si vous ne suivez pas ces instructions à la lettre, un incendie ou une

explosion pourrait se produire et causer des dommages matériels,

des blessures personnelles ou même la mort.

A. Cet appareil n’est pas doté d’une veilleuse. Il est

équipé d’un dispositif d’allumage qui allume
automatiquement le brûleur. Ne tentez
d’allumer le brûleur manuellement.

B. AVANT D’UTILISER, vérifiez s’il n’y a pas

d’odeur de gaz près de l’appareil. Vérifiez s’il n’y
a pas d’odeur de gaz près du plancher, car le
gaz est plus lourd que l’air et peut se déposer
sur le plancher.
QUE FAIRE EN CAS D’ODEUR DE GAZ

• N’essayez pas d’allumer n’importe quelque
appareil que ce soit.

• Ne touchez pas à un commutateur électrique.
N’utilisez pas le téléphone de votre résidence.

• Appelez immédiatement votre fournisseur de
gaz en utilisant le téléphone de votre voisin.
Suivez les instructions de votre fournisseur de
gaz.

pas

• Si vous ne pouvez joindre votre fournisseur
de gaz, appelez le service des incendies.

C. Fermez la soupape d’arrêt de gaz (située au-

dessus de la commande de gaz multifonctions)
de sorte que la poignée soit perpendiculaire au
tuyau de gaz. Si vous ne pouvez tourner la
poignée à la main, n’essayez pas de la réparer.
Communiquez avec un technicien de service
qualifié. Le fait de forcer ou de tenter de réparer
la poignée pourrait causer un incendie ou une
explosion.

D. N’utilisez pas cet appareil si l’une des pièces a

été plongée sous l’eau. Communiquez
immédiatement avec un technicien de service
qualifié afin qu’il inspecte l’appareil et remplace
toute pièce du système de commande et toute
commande de gaz qui aurait été plongée sous
l’eau.

NOTICE D’UTILISA TION

1. ARRÊTEZ ! Lisez l’information de sécurité ci­dessus, sur cette étiquette.

2. Réglez le thermostat au réglage le plus bas.

3. Coupez l’alimentation électrique à l’appareil.

4. Cet appareil est doté d’un dispositif d’allumage
qui allumera automatiquement le brûleur.
Ne tentez

5. Retirez le panneau d’accès aux commandes et le
couvercle avant qui se trouve sur le dessus.

Valve de fermeture

pas d’allumer le brûleur manuellement.

Commande de gaz

multifonctions

du gaz

6. Faites tourner la valve de fermeture du gaz dans
le sens des aiguilles d’une montre et mettez-la
à «off». La poignée sera horizontale. N’employez
pas de force.

7. Attendez cinq (5) minutes afin que le gaz se
dissipe. Si vous croyez sentir une odeur de gaz,
ARRÊTEZ ! Reportez-vous aux instructions B ci­dessous, sur cette étiquette. S’il n’y a pas
d’odeur de gaz, passez à la prochaine étape

8. Faites tourner la valve de fermeture du gaz dans
le sens contraire des aiguilles d’une montre et
mettez-la à «on». La poignée sera verticale.

9. Replacez le couvercle avant et le panneau d’accès
de commandes.

10. Rétablissez l’alimentation électrique à l’appareil,
appuyez sur le bouton «on/off» qui se trouve sur le
panneau de commande, appuyez sur le bouton noir
qui se trouve sur le panneau de commande.

11. Réglez le thermostat à la température désirée.

12. Si l’appareil ne fonctionne pas, suivez les directives
relatives à la fermeture de l’alimentation en gaz et
communiquez avec votre technicien de service ou
le fournisseur de gaz.

FERMETURE DE L ’ALIMENTA TION EN GAZ

1. Réglez le thermostat au réglage le plus bas.

2. Coupez toute alimentation électrique à l’appareil
si celui-ci doit faire l’objet d’un entretien.

3. Retirez le panneau d’accès aux commandes et le
couvercle avant qui se trouve sur le dessus.

4. Faites tourner la valve de fermeture du gaz dans
le sens des aiguilles d’une montre et mettez-la
à «off». N’utilisez pas de force.

5. Replacez le couvercle avant.

30-414A

Endurance

Page 17

SECTION 6.
Boiler Start Up

6A. Common Vent Test

At the time of removal of an existing boiler, the
following steps shall be followed with each appliance
remaining connected to the common venting system
placed in operation, while the other appliances
remaining connected to the common venting system
are not in operation.

1. Seal any unused opening in the common venting

system.

2. Visually inspect the venting system for proper

size and horizontal pitch and determine there is

no blockage or restriction, leakage, corrosion

and other deficiencies which could cause an

unsafe condition.

3. Insofar as is practical, close all building doors

and windows and all doors between the space in

which the appliances remaining connected to the

common venting system are located and other

spaces of the building. Turn on clothes dryers

and any appliance not connected to the common

venting system. Turn on any exhaust fans, such

as range hoods and bathroom exhausts, so they

will operate at maximum speed. Do not operate a

summer exhaust fan. Close fireplace dampers.

4. Place in operation the appliance being inspected.

Follow the lighting instructions. Adjust

thermostat so appliance will operate

continuously.

5. Test for spillage at the draft hood relief opening

after 5 minutes of main burner operation. Use

the flame of a match or candle, or smoke from a
cigarette, cigar or pipe.

6. After it has been determined that each appliance
remaining connected to the common venting
system properly vents, when tested as outlined
above, return doors, windows, exhaust fans,
fireplace dampers and any other gas burning
appliance to their previous conditions of use.

7. Any improper operation of the common venting
system should be corrected so the installation
conforms with the
a. National Fuel Gas Code, ANSI Z223.1

latest edition.

b. Can / CGA - B149.
When re-sizing any portion of the common

venting system, the common venting system should be
re-sized to approach the minimum size as determined
using the appropriate tables in Appendix F in the
National Fuel Gas code, ANSI Z223.1 - latest edition,
and/or Can/CSA B149 Installation Codes.

6A. Common Vent Test

Au moment du retrait d’une chaudière existante,

les mesures suivantes doivent être prises pour chaque
appareil toujours raccordé au système d’evacuation
commun et qui fonctionne alors que d’autres appareils
toujours raccordés au système d’évacuation ne
fonctionnent pas:

1. Sceller toutes les ouvertures non utilisées du
système d’évacuation.

2. Inspecter de façon visuelle le système
d’évacuation pour déterminer la grosseur et
l’inclinaison horiztonale qui conviennent et
s’assurer que le système est exempt

Message

Identifies

Boiler Flow Temp (Supply)
Tank Temp
Return Temp (Boiler Inlet)
On
Off
Lock Out - Combustion Related

Fault Code (Three) There are 8
different Fault Codes defined.

Freeze Protection

Figure 26. Typical Display Identification Codes.

To read or change mode

During operation display will default to supply
temperature. Press temperatures button repetitively.
To sequence through three temperature indicators.

Boiler in standby mode: will operate on call for domestic
water or heat zone demand.

Boiler switched OFF. Press ON/OFF button for “ON”.
After three trials for ignition, will stand in lockout. Press

reset on top of panel to retry.
A fault code may be indicated on the display prior to pushing

the reset button or switching the on-off button or power
switch. Observe code, and note it, for servicing.

Sensor has detected return temperature below 39°F (4°C).

Page 18

LAARS HEATING SYSTEMS

d’obstruction, d’étranglement, de fuite, de
corrosion et autres défaillances qui pourraient
présenter des risques.

3. Dans la mesure du possible, fermer toutes les
portes et les fenêtres du bâtiment et toutes les
portes entre l’espace, où les appareils tojours
raccordés et les autres espaces du bâtiment.
Mettre en marche les sécheuses, tous les
appareils non raccordés au système d’évacuation
commun et tous les ventilateurs d’extraction
comme les hottes de cuisinère et les ventilateurs
des salles de bain. S’assurer que ces ventilateurs
fonctionnent à la vitesse maximale, Ne pas faire
fonctionner les ventilateurs d’été. Fermer les
registres des cheminées.

4. Mettre l’appareil inspecté en marche. Suivre les
instructions d’allumage. Régler le thermostat de
façon continue.

5. Faire fonctionner le brûleur principal pendant 5
min ensuite déterminer si le coupe-tirage
déborde à l’ouverture de décharge. Utiliser la
flamme d’une allumette ou d’une chandelle ou la
afumée d’une cigarette, d’une cigare ou d’une
pipe.

6. Une fois qu’il a été déterminé, selon la méthode
indiquée ci-dessus, que chaque appareil raccordé
au systéme d’évacuation est mis à l’air libre de
façon adéquate. Remettre les portes et les
fenêres, les ventilateurs, les registres de
cheminées et les appareils au gaz à leur position
originale.

7. Tout mauvais fonctionnement du systéme
d’évacuation commun devrait êvacuation
commun devrait être corrigé de façon que
l’installation soit conforme au National Fuel
Gas Code, ANSI Z223.1/NFPA 54 et (ou) aux
codes d’installation CAN/CGA-B149. Si la
grosseur d’une section du systéme devrait être
modifié ppour respecter les valeurs minimales
des tableaux pertinents de l’appendice F du

National Fuel Gas Code, ANSI Z223.1/NFPA 54
et (ou) des codes d’installation CAN/CGA-B149.

6B. Filling the System

1. Open all supply and return valves.

2. Fill heating system to minimum operating
pressure 12 psig.

3. Loosen screw in coin vent and allow any trapped
air to escape. Collect any water that escapes so
that it does not drip on the blower electronics and
damage them. Small amounts of air that may
remain will be purged by the internal pump.
Tighten screw after purging.

*The “manual operation” lever located on the

side of the valve operator requires moderate pressure
to latch the valve open and then again to unlatch it and
allow it to close.

4. Purge all lines by opening vents.

5. Close gas shutoff valve located above gas valve.

6. Turn on 120 volt power, the display will initially
display [
[OFF].

7. If the temperature sensor detects a temperature
below 39°F (4°C) it will display [ICE]. The
appliance will then be in the frost protection
mode. The pump initially runs alone for 5 minutes
or until the flow temperature reaches 45°F (7°C).
(EBP ONLY: When the internal zone valve is
manually* opened the water will be pumped to
the space heating.) This is a good time to ensure
that the system is fully discharged of all air and
the water charge pressure is correct. Should the
water temperature remain below 45°F (7°C) after
5 minutes the appliance will start the ignition
sequence. After three attempts to ignite the
burner control will lock out and display [LO]
(see Figure 25).

8. If the display remains at [OFF], press the on/off
button on the front panel and the reset button on
top of the front panel. The pump and the blower
will start, the display will then flash [
flow temperature) for 1 second intervals and the
actual temperature (e.g., [127]) in degrees F for
3 second intervals. The appliance will attempt to
ignite three times after which it will lock out and
display [LO]. The fan and the pump will then
stop. Ensure that the system is fully discharged
of all air and the water charge pressure is correct.

9. Turn the main electrical supply off.

10. EBP ONLY: Manually reset the internal zone

valve to its normal position (manual level
toward top of actuator).

11. System is now ready for operation.

---

] for five seconds before displaying

] (boiler

6C. Firing Burner

1. Be sure that system has been filled properly and
is leak tight.

2. Open gas shutoff valve.

3. Turn on main electrical switch.

4. If the temperature sensor detects a temperature
below 39°F (4°C) it will display [ICE]. The
appliance will then be in the frost protection
mode.

5. If the display remains at [OFF], press the on/off
button on the front of the control panel and the
reset button on top of the control panel.

6. The pump and the blower will start, the display
will show [
1 second intervals and the actual temperature
(e.g., [127]) in degrees F for 3 second intervals.

] (boiler flow temperature) for

Endurance

Page 19

The appliance will attempt to ignite three times,
if ignition is not successful, the appliance will
lock out and display [LO]. Ignition reset is done
by pressing the reset button on top of the control
panel. EBP models will then operate to heat the
transfer tank.

7. EBP ONLY: Turn on a hot water tap. This puts
the appliance in the DHW mode.

Caution

Should any pronounced odor of gas be detected, or
if the gas burner does not appear to be functioning
in a normal manner, close main shutoff valve, do not
shut off switch, and contact your heating contractor,
gas company, or factory representative.

You MUST check flame monitoring control

(ignition system safety shut off device).

1. Close gas shutoff valve with burner operating.

2. The flame indicator light will go out and blower
will continue to run for the post purge cycle.
Three additional attempts to light will follow
including pre-purge, ignitor on, valve/flame on
and post purge. Ignition will not occur as the gas
is off. The display will eventually show [LO]
approximately 10 seconds after the gas valve has
closed on the third ignition attempt.

3. Open gas shutoff valve. Press reset button on the
top of the control panel. The ignition sequence
will start again and the burner will start. The
appliance will return to its previous mode of
operation.

6D. Mode and On/Off Buttons Operation

The on/off button it is used to switch the

appliance from standby [ON] to standby [OFF] and
vice versa. It is NOT an isolation switch. The mode
button accesses all other functions as described in
their particular sections of this manual.

SECTION 7.
Maintenance and Component
Description

7A. Unit Pump

The unit pump operates whenever there is a call

for heat or hot water.

It is a wetted-rotor type pump and should always

be filled with water when it is operating so that it will
cool properly.

If a pump change is required for any reason,

valve off the boiler and drain approximately 1 or 2

gallons (approx. 4-8L) of water from it. Turn off the
main disconnect switch and unplug the pump wires,
remove the pump motor. The pump housing need not
be removed. The replacement pump motor should be
installed in the reverse order from which the old pump
motor was removed. After filling the system be sure
the combustion chamber coil vents through the air vent
located on top of the boiler chamber (inlet manifold
extension).

7B. Gas Valve

The gas valve is a 24VDC solenoid operated,
negative pressure regulated ratio valve. The outlet
pressure may be adjusted as described in the service
section. It is designed to operate with supply pressures
of 4-13 inches w.c. (1.0 to 3.2 kPa). To remove the gas
valve, shut off 120 volt power and the gas shutoff
valve, remove the 4 screws on the upper and lower
flanges and disconnect the wires from the gas valve,
the valve may now be removed. After the valve has
been removed, replace with a new valve in the reverse
order in which the old valve was removed. Turn on gas
shutoff valve and 120 volt power and check boiler
operation and gas tightness of gas valve connections.

7C. Safety Limit Switch

The Safety Limit Switch is an automatic reset
switch with a fixed set point of 230°F (110°C). To
replace the switch, shut off the 120 volt power.
Disconnect the 2 wires from the quick connects at the
switch and remove the switch. To replace, perform the
same operations in reverse. Turn on disconnect switch
and check boiler.

7D. Boiler Control Printed Circuit

Board (PCB)

The Integrated Boiler Control Module controls
the ignition process, the combustion process, the
temperature of the boiler flow and return, and the
transfer tank temperature* and provides both domestic
hot water* and space heating on demand.

To do this it takes inputs from three temperature
sensors, a domestic hot water flow switch, an overheat
thermostat (safety limit) and an external space heating
switch, such as a room thermostat, zone valve end
switches or circulator relay contacts. It then controls
the pump, blower, ignitor and gas valve sequencing.

It constantly displays the boiler outlet
temperature when the appliance is operating in one of
its demand modes. It also allows the user to obtain
information from the appliance to determine the water
temperature at three different locations within the
appliance and to find up to 8 previous faults stored in
memory.

If replacement of PCB is necessary, shut off the
120 volt power and disconnect the wire connectors
from the pcb. Remove the PCB from its location posts.

Page 20

LAARS HEATING SYSTEMS

Replace in reverse order ensuring that the connections
are correct.

*EBP combination units only.

7E. Ignitor / Flame Sensor Assembly

The ignitor is a “glow bar” type ceramic
composite device. It is energized whenever there is a
call for heat and switched off when ignition is
established.

The flame sensor is a remote sensing flame rod
which is connected directly to the circuit board “J5”
terminal. The ignitor should read 50 to 100 ohms
resistance when at room temperature.

If the ignitor fails and the assembly must be
replaced, always install a new ignitor gasket with the
replacement assembly.

For sequence of operation, see Section 8,
Servicing.

Caution

Ignitor gets hot.

7F. Transformer

The control transformer accepts 120 VAC line
voltage and provides 80 VA of 24 VAC control
voltage for the boiler control ONLY. It is NOT
capable of supplying control voltage for external
devices such as zone valves, which MUST have their
own separate power supply.

Should the transformer require replacing, shut off
the 120 volt power. Unplug the transformer wires from
the PCB, unscrew the two fixing screws and remove
the transformer.

Fit the replacement transformer in reverse order.

7G. Blower

The combustion air blower is a high pressure
centrifugal blower. It is powered by a 24VDC motor
which is controlled by the PCB. Its speed will be
varied according to the temperature of the boiler flow.

If a blower change is required, turn off the 120
volt power and unplug the wires from the blower
motor. Remove the four nuts from the blower
discharge flange and the four screws that secure the
gas manifold to the gas valve. Remove the complete
assembly. Unscrew the combustion air inlet assembly
and register plate from the fan.

Fit the replacement fan in reverse order, ensuring
that all joints are made correctly and sealed.

After replacement the combustion should be
checked for correct air fuel ratio (see Check, Test and
Start-Up section).

7H. Transfer Tank (EBP)

The transfer tank contains approximately 20
gallons of boiler water. It functions as an energy

storage vessel to reduce boiler cycling on small output
heating zones and to provide additional heat for
domestic hot water through the domestic hot water
(DHW) plate heat exchanger.

If a tank change is necessary, access to the tank
is possible by removing the jacket’s lower front panel.
This is done by removing the screws that hold the
panel at the top and lifting the panel away. Isolate the
appliance and drain down using the drain cock at the
base of the tank. Remove the tank sensor. Undo the
union and the pump flange bolts that connect the tank
to the boiler, unscrew the panel between the upper and
lower compartments, support the upper components
and remove the tank. Installation of the new tank is
done in the reverse order. After installation purge all
air from the boiler before restarting.

7I. Thermostatic Union (EDP/EDN)

The thermostatic union is a 1¼" NPTF union
which must be mounted at the flow outlet to control
boiler temperature. The union must be installed so that
union nut is on the boiler side of the connection. This
insures that the thermostat is properly positioned with
its spring facing up, toward the system. The element
has two small bypass holes that allow some water to
flow into the system at all times. When the boiler first
starts and the element is closed, boiler water is re­circulated back to the return until the supply water
reaches 160°F (71°C). The element then modulates
open. If the temperature does not exceed 150°F (66°C)
within two minutes after firing, the element is not
functioning properly. To replace the element, shut off
and drain the section of the system adjacent to the
thermostatic union. Open the union and replace the
element with a new one. The element should be
installed so that its spring and actuator are facing the
system side (up). Close the union, open the valves,
refill and bleed the system. Ensure that air is venting
from the air vent on top of the boiler chamber and it is
left operational. Restart boiler.

7J. Cleaning the Boiler Coil

The Endurance is equipped with a premixed
combustion system. This type of combustion system
does not create free carbon (soot) except in very rare
instances and therefor the combustion chamber coil
will probably never need cleaning. If cleaning is
required, proceed as follows: valve off the boiler,
switch off the electrical power at the disconnect
switch, drain 1-2 gallons (4-8L) of water from the
boiler drain, remove the flue assembly from the top of
the boiler, remove the pump flange bolts from the top
pump flange, disconnect the sensor wires from the
sensors (boiler flow, return and safety limit), undo the
union nut from the boiler flow manifold, and remove
the four (4) screws from the bottom gas valve flange.
The boiler assembly may now be removed from the
jacket. After removal of the boiler assembly from the

Endurance

Page 21

jacket, remove the four (4) long screws that secure the
top and bottom pans. Remove the air vent and the top
pan. Remove the insulation retainer and the coil cover
insulation. Clean the boiler coil with a wire brush and
vacuum debris from the combustion chamber (avoid
hitting the ignitor or the flame sensor with the brush
or vacuum hose because they are fragile).

After cleaning, assemble the parts in the reverse
order, open isolation valves and bleed air from the
boiler and the system. Follow the lighting instructions
and start the boiler. Check operation.

SECTION 8
Servicing.

8A. Sequence of Operation

Figures 22 and 23 depict the flow paths and
temperature sensor locations for the space heating,
EDP/EDN, and the combined space heating and
domestic water heating, EBP, appliances.

The model EDP/EDN modulating boilers are
cold start boilers that will start only on a call for heat
from a room thermostat or zone control contact.
During normal operation the Message Center [MC]
LED display will indicate ‘ON’ while awaiting a call
for heat. On a call for heat the following sequence
will occur.

1. (a) The internal pump will start.

(b) After 5 seconds the blower prepurge cycle

will start and operate for approximately 6

seconds while the [MC] indicates alternately

and the current boiler outlet temperature.

2. Following the prepurge cycle the ignitor will
heat for 10 seconds while the blower continues
to operate.

3. The gas valve will then be energized (green
‘GV’ LED located on the PCB next to the
display will light) and open, gas will flow and
ignition will occur.

Figure 27. EDP/EDN Flow Schematic.

Figure 28. EBP Flow Schematic.

Page 22

LAARS HEATING SYSTEMS

4. 10 seconds after establishing combustion and
proof of flame ( via the flame rod signal to
ground ), the ignitor will be de-energized and
the burner will modulate to high fire for
maximum output.

5. The [MC] should indicate a rapid rise in
temperature to 150º F (1-2 min. duration).
During this period the thermostatic union at the
flow outlet is closed and the boiler is operating
in the internal recirculation mode. [Service note:
If the temperature rise is not rapid the union
thermostat may be defective and must be
replaced].

6. At 150° F the thermostat will allow increased
flow to the system and a gradual rise in
temperature will be indicated until the
temperature approaches the setpoint temperature
of 180ºF. The firing rate will start to modulate
downward until its cutoff limit is reached or the
call for heat is satisfied.

The EBP modulating combination boiler will

start from any of three input signals: (a)T-T closure
for space heating. (b)A demand for domestic hot
water, signaled by water flow activation of the water
flow switch. (c)A call for heat from the minimum
tank temperature sensor at 158°F (tank charge mode).
In tank charge mode the red LED located below the
green LED on the PCB will be lit. In modes (b) and
(c) which are priority modes, the internal anti­condensing valve will be closed. On a T-T call for
heat the valve will remain closed until the priority
modes are satisfied.

[Service note: as with the thermostatic union in

the EDP/EDN models, the anti-condensing valve
prevents condensation on the combustion chamber
coil and must be in the closed position when the coil
inlet (F6) indicates a temperature below 130°F].

8B. Trouble Shooting - Fault Codes

The Endurance boiler is controlled by a Pactrol

integrated boiler control (PCB) which provides eight
fault codes with eight memories. To obtain fault
messages press-in on the message center fault button
until the first fault code (FLI) is displayed.

If a thermistor error occurs, it will appear on the

LED upon power-up. The memory does not need to

be accessed. Memory fault codes are for error
history only. All thermistor faults will show as “F”
codes on the LED, and will never cause the LED to
read “LO”. (Note that the unit is shipped with error

codes already in memory, and an error code that is
shown in memory upon start-up of a new unit is from
manufacturing testing.)

The last recorded fault will appear e.g. F-4 (flow

thermister faulty - open or shorted). The control will
then sequence through all eight memories, indicating
alternately the fault number and the fault code (FL1,

F-?; FL2, F=?; …, FL8, F=?). The fault number in
fault code FL1 is the most recent fault.

8B-1. Fault Code Identification

The following eight fault codes may be observed:
F- Error corrected, control in auto reset time

period (10 seconds)
F-0 No fault has occurred
F-1 Error occurred reading fault logic of main

control
F-2 Over heat thermostat has operated

(open circuit)
F-3 Fan fault
F-4 Flow temperature sensor faulty

(open or short circuited)
F-5 Tank temperature sensor faulty

(open or short circuited) (Combi unit only)
F-6 Return temperature sensor faulty

(open or short circuited)

8B-2. Fault Correction (see also Fault

Trees in this Section)

F-1 Switch off boiler and restart. If F-1 repeats,

replace PCB
F-2 The overheat thermostat (safety limit)

opens at 230°F. Observe boiler operation if

the boiler shuts off before the

indicates 225°F (107°C) replace safety

limit. If the temperature rises rapidly and

the safety limit operates, the internal pump

is not operating. Refer to the wiring

diagrams and check for voltage (120V)

across the terminals on the PCB marked PMP.

a. If there is no voltage, and the PCB

display does not indicate on or off,
replace PCB

b. If there is voltage, the pump or wiring

is defective.

F-3 Attempt to start the boiler. Check

combustion air blower operation. If F-3 is

indicated again, replace blower.
F-4 Check for damaged wiring or poor

connection at sensor plug. If they are OK

disconnect the sensor plug and check the

resistance across the sensor terminals. The

resistance of a good sensor is 10,000 ohms

@ 77°F (25°C). Replace sensor if

resistance is less than 500 or more than

20,000 ohms.
F-5 Correct in the same manner as F-4.
F-6 Correct in the same manner as F-4.

8B-3. Resolving Lockouts (LO)

(The memory does not need to be accessed.

Memory fault codes are for error history only. All
thermistor faults will show as “F” codes on the
LED, and will never cause the LED to read “LO”.

There are many causes for lockouts. The five

most common causes are: (1) poor combustion,

Endurance

Page 23

POWER UP

F AULT TREE

Page 24

LAARS HEATING SYSTEMS

IGNITION FAULT TREE

Endurance

Page 25

SPACE HEA TING

F AULT TREE

Page 26

LAARS HEATING SYSTEMS

DOMESTIC HOT WATER

FAULT TREE (EBP ONLY)

Endurance

Page 27

BOILER TEMPERATURE

F AULT TREE

Page 28

LAARS HEATING SYSTEMS

(2) poor flame sensor signal, (3) inadequate gas
supply, (4) ignitor failure, (5) blocked or
contaminated air source.

1. Poor Combustion: Poor combustion should be
suspected if there is a strong flue gas odor. The
odor may result from either an improper gas/air
ration (high or low CO

2) or contamination of the

combustion air supply. If an improper gas/air
ratio is suspected refer to “gas valve calibration
(offset adjustment)” on page 25. If
contamination of the air source is suspected refer
to (5) below.

2. Poor flame sensor signal: The boiler control
board will lockout if the flame sensor is
grounded or if the flame signal it receives is less
than 1 mA dc. To check for a grounded sensor,
remove the flame sensor wire (yellow) from the
boiler control board and check for continuity
between the yellow wire terminal and the
combustion chamber bottom pan. If there is
continuity, the flame sensor is grounded. An
alternate way to check for grounding of the
flame sensor is to check the ohms resistance
between the yellow wire terminal and the
combustion chamber bottom pan, using a meter
set for at least 100,000 ohms. The resistance
must be more than 250,000 ohms (some
technicians have been confused by meters which
report infinite resistance with what appears to
them as double zeros; an infinite resistance
reading means there is no grounding of the flame
sensor.) If there is continuity, or the ohms
resistance is less than 250,000 ohms, debris or
moisture in the combustion chamber may be the
cause. To correct, carefully remove the ignitor
and flame sensor assembly. Look for debris on
the assembly where the flame rod exits the
ceramic tube. If debris exists, remove it. If this
area is clean, insert a pencil or other round
object into the flame sensor hole in the bottom
combustion chamber pan and roll it around to
clear any debris that may exist inside the
combustion chamber. Replace the ignitor/flame
sensor assembly, reconnect the yellow wire on
the PCB and start the boiler. If lockout persists,
check the flame signal. To check the flame
signal, disconnect the yellow wire from the
flame sensor, connect a meter, set for microamps
(mA) DC, between the flame sensor connector
and the yellow wire connector. Start the boiler. If
the meter reading is less than 1.00 mA DC, see
(3) “poor combustion” below. (Check for air
leaks at air inlet to blower.)

3. Inadequate gas supply: Before proceeding,
ensure that the gas supply has not been shutoff
or the LP tank (LP boilers) is not empty. Then,
reset the boiler and observe the operational

MEASUREMENTS AT HIGH FIRE

NATURAL GAS

% CO2 9.0 - 9.6

MAX INPUT

BTU/H

OFFSET

IN W.C.

LP GAS

% CO2 9.7 - 10.1

MAX INPUT

BTU/H

OFFSET

IN W.C.

Table 4. EBP/EDP 175.

Figure 29.

Figure 30. Jumper Wiring for Test and Calibration.

175,270

(-0.01 to -.10)

175,270

(-0.01 to -.10)

cycle. Approximately 20 seconds after the start
of the cycle, the GV LED on the PCB should
light. If it does not, reset the boiler and check for
24 VAC at the plug on the PCB. If the voltage is
less than 20 VAC, and transformer voltage is 24
VAC replace the PCB. If the voltage is correct,
connect a pressure gauge to the offset pressure
port on the gas valve. Reset the boiler and

Endurance

Page 29

Caution

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

Verify proper operation after operation servicing.

Figure 31. EDP/EDN Wiring Diagram.

ATTENTION

Au moment de l’entretien des commandes,
étiquetez tous les fils avant de les débrancher. Les
erreurs de câblage peuvent nuire au bon
fonctionnement et être dangereuses.

S’assurer que l’apperiel fonctionne adéquatement
une fois l’entretien terminé.

Page 30

LAARS HEATING SYSTEMS

Caution

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

Verify proper operation after operation servicing.

Figure 32. EBP Wiring Diagram.

ATTENTION

Au moment de l’entretien des commandes,
étiquetez tous les fils avant de les débrancher. Les
erreurs de câblage peuvent nuire au bon
fonctionnement et être dangereuses.

S’assurer que l’apperiel fonctionne adéquatement
une fois l’entretien terminé.

Endurance

Page 31

observe the offset pressure at startup and after 20
seconds. The pressure will be ~ -2 in. w.c. at
startup (during prepurge) and should become
less negative (-0.1 in. w.c.) when the gas valve
opens and gas flow starts. If the pressure remains
at ~ -2 in. w.c. throughout the cycle replace the
gas valve.

4. Ignitor failure: If the boiler goes through a
normal start cycle but combustion does not
occur, ignitor failure should be suspected.
Check the ignitor by unplugging the ignitor plug
and measuring the ignitor resistance. It should be
50-100 (W) ohms. If the resistance is not 50-100
ohms (W), replace the ignitor. If the resistance is
correct, reset the boiler and check for 120 VAC
at the ignitor plug during the start cycle. If there
is no voltage, replace the PCB or faulty ignitor
wires.

5. Blocked or contaminated air source: Before
proceeding, ensure that the vent terminal (Direct
Vent installations) or the air inlet (Category IV
installations) is not obstructed. In general, only
direct vent installations have the potential for
cross contamination (flue products entering the
combustion air stream) of the combustion air
source. This may be caused by leaky joints in the
3" flue pipe located inside the 5" combustion air
pipe. If this is suspected, remove the front panel
from the appliance, reset the boiler and allow it
to go through a normal cycle. If during this cycle
there is no flue odor, repair the leaky joints in
the flue pipe.

SECTION 9.
Gas Valve Calibration

9A. Gas Valve Calibration

(offset adjustment)

If poor combustion is suspected because of a

strong exhaust smell, pulsation in the exhaust, or
nuisance flame failure lockouts (shown as “LO” on
LED), the gas valve offset pressure and exhaust CO
should be checked and adjusted, if required. A
magnehelic pressure gauge (with 0.1 in. w.c.
divisions) and a CO

2 tester are required for this

adjustment.

Note: Direct vent installations may experience

poor combustion that results from cross contamination
of the combustion air source. Check for cross
contamination before attempting offset pressure
adjustment (see Section 8B-3.5).

CO

2 sampling may be taken at the exhaust

terminal or at the sample port on the 3” exhaust
located inside the front panel top cover. See Figure 28
for the location of the offset pressure port and offset
adjustment.

2

The CO

2 values shown in Table 4 should be

achieved when the unit is in high fire. To manually fix
the unit in high fire, locate the four-pin connector on
the bottom left of the control board, and jumper the
middle two terminals together (see Figure 29). NOTE:
For EBP (combination heat & hot water) units, when
the unit is in “tank charge” mode it will stay in high
fire, whether manually jumpered or not.

Note: During the prepurge cycle, the gauge will

indicate several in. W.C. negative pressure.

Adjust the CO

2 and/or offset pressure to the

values shown in Table 4.

When adjusting the offset pressure, the CO

2 will

reduce as the offset pressure is adjusted more
negative. FINAL ADJUSTMENT OF THE

OFFSET PRESSURE MUST ALWAYS RESULT
IN A NEGATIVE PRESSURE UPON
COMPLETION.

SECTION 10.
Symptom Evaluations

10A. Delayed ignition

Possible Causes

a. High lockup pressure (LP boilers) - occurs on

start-up.
b. Gas valve regulation problem - occurs on start-up.
c. Incorrect gas orifice (Natural gas orifice in an LP

boiler) - occurs on start up
d. Defective burner - occurs on startup or at burner

shutdown.

High lock up pressure is the most common cause
of delayed ignitions on LP fueled boilers. It may result
from an improper second stage regulator selection or
from a faulty regulator.

Lock up can be detected by measuring the gas
supply pressure to the boiler at the inlet pressure tap
on the gas valve. The gas supply to the boiler must be
shut off before making this connection. Use a water
manometer or pressure gauge with a scale reading of
at least 25 in. w. c. or 15 oz/in
the gas valve pressure port one full turn and install a
hose from the pressure gauge over the pressure port.
Turn on the gas supply. The ENDURANCE boiler is
designed to operate with supply pressures of 4-13 in.
w. c. (2.3 - 7.5 oz/ in²). If the supply pressure exceeds
13 in. w. c. (7.5 oz/ in²) with the boiler not operating it
is possible that this may be the cause of delayed
ignitions and the pressure must be reset to ~ 9 in. w. c.
(5.2 oz/ in2). Restart the boiler and then switch it off
again. Lock up pressures
boiler is not operating and preferably immediately
after boiler shutdown. If the gas pressure again
exceeds the allowable values, correct the lock up
problem.

2

. Loosen the screw in

must be measured when the

Page 32

LAARS HEATING SYSTEMS

Gas valve regulation problems can also cause

delayed ignitions. See “Gas valve calibration”.

Incorrect gas orifice – Check orifice size.

A defective burner can cause a delayed ignition
during operation or at shutdown. If the gas supply
pressure is proper the gas valve is functioning
properly and the gas orifice is correct, the burner
should be inspected. To inspect it, remove the
blower. The burner is retained by the blower and it
will drop out of the bottom of the chamber when the
blower is removed. There should be

no distortion or
perforations in the burner other than the punched
holes. Replace if indicated.

10B. Short Cycling

Possible causes
a. Reduced system flow - EDP
b. Thermostatic union (EDP) or anti-condensing

valve not opening (EBP).
c. T-T wires cross connected (jumped) –

improper

installation - EBP or EDP/EDN

d. Leakage of flue products into the combustion air

stream – Direct Vent Installations only, see

Section 8B-3, Resolving Lockouts (LO), item (5).

10C. Noisy Operation

There are two principal sources of noisy
operation:

a. Combustion - high pitched noise - whistle or

hoot.
b. Boiling (kettling) - lower frequency noise which

varies with temperature - moan.

Many times it is difficult to determine the source
of the noise or if it is combustion related or boiling
related. Combustion noises always have the same
frequency; however, their volume may change from
the time that the burner first fires to the time that it
shuts off. A boiling noise is identified by rapidly
raising or lowering the system water pressure while
the noise is present. A change in the pitch or intensity
of the noise indicates a boiling problem.

Combustion noise occurs at any boiler
discharge temperature and is heard the loudest at the
flue outlet (especially on units that are sidewall
vented). There are two basic causes for the noise, rich
mixture (high CO
The mixture is determined by measuring the percent
O

2 or CO2 in the flue products. O2 readings lower than

4½ % or CO
and 10.8% (LP) will often cause combustion related
noise. The rich mixture could be caused by the mis­calibration of the gas valve (offset adjustment) or by
the gas orifice size. To eliminate the noise; first, check
the gas valve calibration. If it is correct, install a
smaller gas orifice so that the O
or the CO

2 will drop to 8½% (natural) or 9½% (LP).

2 or low O2) or cross contamination.

2 readings higher than 9¼ % (natural gas)

2 will rise above 4½%

The CO

2 & O2 readings may be influenced by

cross contamination. Suspect cross contamination if
the noise returns when the front panel is replaced.

Boiling (kettling) may occur at boiler discharge

temperatures from 170°F to 210°F. The temperature
at which it starts will vary from one installation to
another. The primary cause of the problem is poor
heat transfer on the inside of the boiler coil. This may
be caused by foaming due to excessive concentration
of antifreeze in the system or by scaling from the
boiler water due to hardness of make up water.

Plumbing antifreezes should never be used in a
boiler system. Only boiler antifreezes, with effective
antifoamants, are appropriate for the ENDURANCE
boilers.

Note: The concentration of appropriate
antifreeze should be always be kept as low as possible
to minimize its effect on heat transfer and efficiency.

The method for eliminating the boiling noise is
the same regardless of the cause. However, if
antifreeze in the system is suspected of being the
cause, the concentration (<35%) and type should be
investigated.

Moisture

Although it is not a primary cause of lockouts,
moisture in the combustion chamber may cause
lockouts by weakening the flame signal to the boiler
control. It should be suspected if the boiler
temperature does not rise above 160°F during long
periods of operation. This condition can be caused by
a defective thermostat in the thermostatic union of
EDN or EDP boilers (or the omission of the
thermostatic union at installation) or failure of the
anticondensing valve in the EBP (combi) boilers.
Moisture can also get into the combustion chamber
through an incorrectly pitched or incorrectly installed
flue pipe (pitched back toward the boiler without a
condensate trap). The flue assembly of EBP, EDN and
EDP boilers installed as Direct Vent boilers should
always pitch down from the boiler.

10D. Insufficient Hot Water (EBP only)

Possible cause:
a. No flow restrictor (supplied with unit - field

installed)
b. Water flow switch failure
c. Mixing valve setting or failure
d. Domestic hot water (DHW) heat exchanger

contamination

The most common cause for insufficient hot
water complaints results from failure to install a flow
restrictor. The absence of a flow restrictor allows
water to pass through the heat exchanger at a greater
rate than the boiler output is capable of heating to the
desired temperature.

Failure of the water flow switch to operate
during a hot water draw prevents boiler water from

Endurance

Page 33

flowing through the DHW heat exchanger and
therefor the DHW will not be heated.

To test the switch, place a temporary jumper

across the back of the connector on the PCB (see
wiring diagrams for connector location). If the internal
pump operates and there is DHW generated then the
water flow switch is faulty and must be replaced.
Note: Switch orientation is critical for proper switch
operation, The identification plate on the switch must
face up and the arrow on the plate must point in the
direction of flow.

Failure of the mixing valve will allow cold water
to be mixed with the hot water from the DHW heat
exchanger during a DHW draw regardless of the
setting of the mixing valve or the temperature of the
water leaving the DHW heat exchanger. The failure
can be detected by observing the temperature of the
three pipes connected to the mixing valve. If the
“mix” temperature is luke warm or cool and the “hot”
temperature is hot and the “cold” temperature is cold
then the mixing valve is either faulty or incorrectly
adjusted and must be replaced or adjusted.

DHW heat exchanger scaling may occur in some
areas of the country where there are high
concentrations of minerals in the water. These
minerals may cause fouling of the DHW heat
exchanger over an extended period of time (lime build
up). Other minerals, which react more quickly in well

systems (mostly magnesium), cause slime on the
inside of the heat exchanger and prevent adequate heat
transfer. These minerals must be filtered out by a
special incoming water filter or by the addition of an
inhibitor to protect the coil and provide acceptable
water quality. Minerals may be removed when
necessary by flushing the coil with a cleaner such as
“Unlime®” or “Sizzle®”.

10E. High Gas Consumption

Boilers operating with an improper air/fuel ratio
are very inefficient and consequently, have very high
gas consumption. Because efficiency is high when the
CO

2 is high, boilers operating with low CO2

(especially LP boilers) consume more gas. Adjust the
CO

2 or O2 for optimum efficiency. If no combustion

analyzing equipment (CO
proper adjustment of the air/fuel ratio (CO
be accomplished. However, by briefly sniffing the flue
gases it is possible to determine if the CO
within the proper range. There is no significant flue
gas odor when combustion is proper. A strong
piercing smell indicates poor combustion and
generally a lean mixture (low CO
calibration (offset adjustment) and adjust if indicated.
Do not attempt to correct combustion by reorificing
without an O

2 or CO2 kit.

2 or O2) is available then a

2) can not

2 or O2 is

2). Check gas valve

Page 34

LAARS HEATING SYSTEMS

SECTION 11.
Parts Identification

Description Part

Number

1. PAN, COMBUSTION CHAMBER T0P 2400-502

2. PAN, COMBUSTION CHAMBER BOTTOM 2400-504

3. INSULATION, COIL COVER 2400-506

4. INSULATION, BOILER COIL 2400-508

5. COIL, BOILER, EBP/EDP/EDN 110 (ASSY.) 2400-510

6. COIL, BOILER, EBP/EDP/EDN 175 (ASSY.) 2400-512

7. GASKET, BURNER 2400-514

8. BURNER, EBP/EDP/EDN 110
(GASKETS INCLUDED) 2400-516

9. BURNER, EBP/EDP/EDN 175
(GASKETS INCLUDED) 2400-518

10. TRANSFER TANK 2400-520

11. BOILER DRAIN (BEHIND PANEL-EBP) 2400-522

12. BLOWER, COMBUSTION AIR
(GASKETS INCLUDED) 2400-524

13. IGNITOR/FLAME SENSOR
(GASKET INCLUDED) 2400-526

14. GASKET, IGNITOR/FLAME SENSOR 2400-528

15. COIN VENT 1-592

16. COMBUSTION AIR INLET,
ADJUSTABLE, KIT 2400-142

17. VALVE, ANTI CONDENSING,
REPAIR KIT 2400-538

Description Part

Number

18. GASKET, BLOWER 2400-540

19. WATER FLOW SWITCH 2400-542

20. BOILER CONTROL (BEHIND PANEL) (EBP) 2400-546

21. GAS VALVE, HONEYWELL,
NEG. REG. PRESSURE 2400-548

22. SAFETY LIMIT, 230 °F 2400-550

23. SENSOR, TANK ( EBP ONLY ) 2400-552

24. SENSOR, BOILER FLOW 2400-554

25. SENSOR, BOILER RETURN 2400-556

26. THERMOSTATIC UNION EDP (NOT SHOWN)2400-030

27. GAS SHUTOFF VALVE 2400-560

28. PUMP, EBP/EDP 110 2400-592

29. PUMP, EBP/EDP 175 2400-386

30. GASKETS, PUMP FLANGE 2400-566

31. RESET SWITCH 2400-568

32. HEAT EXCHANGER, DOM. HOT WATER 2400-570

33. GASKETS, DHW HEAT EXCHANGER 2400-572

34. BUTTON, ON/OFF (PART OF 2400-546) -

35. BUTTON, TEMP/MESSAGE
(PART OF 2400-546) -

36. GAUGE, PRESSURE (NOT SHOWN) 2400-574

37. PRESSURE RELIEF VALVE
(30 PSIG, NOT SHOWN) 2400-112

38. BOILER CONTROL (BEHIND PANEL)
(EDP/EDN) 2400-558

39. PUMP, EDN 110 2400-388

40. PUMP, EDN 175 2400-388

41. THERMOSTATIC UNION EDN (NOT SHOWN)47-026

42. TRANSFORMER (NOT SHOWN) 2400-562

Model EDP/EDN

Endurance

Page 35

Boiler Drain

Model EBP

P.O. Box 310 
Lynnfield, MA 01940 
Phone: [phone] 
Fax: [phone]

As an Energy Star® Partner,

Laars has determined that this
product meets the Energy Star®
guidelines for energy efficiency.