LAARS NTV600 User Manual

Addendum to Instructions

Vent and Air Intake Lengths for use with

Laars Neotherm NTH600 & NTV600 Appliances

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. For indoor installations, as an additional
measure of safety, Laars strongly recommends installation of suitable Carbon Monoxide detectors in the
vicinity of this appliance and in any adjacent occupied spaces.

This Addendum applies to the following Document:

Models Affected Size Part No. Doc. No.

NeoTherm (NTH, NTV) 600 H2335500G Doc. 1218G

Change to Table 2. (page 11):

Description of Change: In the interest of continuing

product improvement and maintaining product reliability
and safety, Laars has revised the allowable exhaust vent
and combustion air intake lengths for the NTH600 and
NTV600 boilers as follows:

4" diameter PVC, CPVC or stainless material is allowed
in lengths up to 40 equivalent feet for each intake and
vent section.

6" diameter PVC, CPVC or stainless material is allowed
in lengths up to 100 equivalent feet for each intake and
vent section with the following considerations:

For any combination of vent and intake lengths up to 40
equivalent feet, any even or uneven combination of length is
allowed.

For overall lengths greater than 40 equivalent feet, the
exhaust may be up to 20 feet greater than the intake length.

Example 1: If the exhaust is 40 equivalent feet, then the
intake length can be zero, and as long as 40 equivalent
feet.

Example 2: If the exhaust is 90 equivalent feet, then the
intake length can be as little as 70 equivalent feet, and as
long as 100 equivalent feet.

Example 3: If the exhaust is 50 equivalent feet, then the
intake length can be as little as 30 equivalent feet, and as
long as 100 equivalent feet.

INTAKE / EXHAUST

STANDARD MAX EQUIV. OPTIONAL MAX EQUIV.

SIZE VENT FT. M VENT FT. M

80 2" 40 6.1 3" 100 30.5
105 2" 40 6.1 3" 100 30.5
150 3" 100 30.5 n/a — —

199/210 3" 100 30.5 n/a — —

285 4" 100 30 n/a — —
399 4" 100 30 n/a — —
500 4" 100 30 n/a — —

*600* 4" 40 6.1 6" 100 30

750 4" 40 6.1 6" 100 30
850 4" 40 6.1 6" 100 30

Installations in the U.S. require exhaust vent pipe that is a combination of
PVC & CPVC complying with ANSI/ASTM D1785 F441 or stainless
steel complying with UL1738. Installations in Canada require exhaust
vent pipe that is certified to ULC S636.

Intake (air) pipe must be PVC or CPVC that complies with ANSI/ASTM
D1785 F441, ABS that complies with ANSI/ASTM D1527 or galvanized
material.

Installer must comply fully with manufacturer's installation instructions,
including use of minimum exhaust length CPVC, to maintain ANSI
Z21.13 safety certification.

Closet and alcove installations do not allow the use of PVC under any
circumstances

To calculate max equivalent length, measure the linear feet of the pipe,
and add 5 feet (1.5m) for each elbow used.

For any combination of vent and intake lengths up to 40 equivalent feet,

*

any even or uneven combination of length is allowed. For overall lengths
greater than 40 equivalent feet, the exhaust may be up to 20 feet greater
than the intake length.

Table 2. Vent / Air Pipe Sizes.

Litho in U.S.A. © Laars Heating Systems 1109 H2350600-

Addendum to Instructions

Polypropylene Vent Material for use with

Laars NeoTherm and Mascot II Appliances

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. For indoor installations, as an additional measure of safety, Laars strongly
recommends installation of suitable Carbon Monoxide detectors in the vicinity of this appliance and in any adjacent
occupied spaces.

This Addendum applies to the following:

Models Affected Sizes Part No. Doc. No.

NeoTherm (NTH, NTV) 80-850 H2335500 1218

Mascot II (LMH, LMC) 125 H2338100A 1230

Description of Change: The use of polypropylene vent material has been accepted by CSA for use with exhaust
and combustion on NeoTherm and Mascot II appliances. The polypropylene component manufacturer shall have ULC­S636 approval with a recognized listing agency for all components used in the venting system. All components used
must be from the same manufacturer and designed for use with exhaust temperatures at or below 195°F (90°C).

Please reference the current edition of the appliance installation and operation instructions for proper vent sizing.
Only approved pipe diameters, lengths, and, arrangements associated with the specific model size allowed.

The installer shall refer to the polypropylene component manufacturer's approved installation and application
instructions for their specific assembly requirements.

800.900.9276 • Fax [phone] (Customer Service, Service Advisors)

20 Industrial Way, Rochester, NH 03867 • 603.335.6300 • Fax [phone] (Applications Engineering)

1869 Sismet Road, Mississauga, Ontario, Canada L4W 1W8 • 905.238.0100 • Fax [phone]

www.Laars.com Litho in U.S.A. © Laars Heating Systems 1106

H2348400-

Installation and Operation Instructions Document 1218G

Installation and Operation
Instructions for

®

NeoTherm

Modulating Boiler
Model NTH

Sizes 080–850 MBTU/h

Water Heater
Model NTV

Sizes 150–850 MBTU/h

FOR YOUR SAFETY: This product must be installed and serviced by a professional service technician,
qualified in hot water boiler and heater 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.

WARNING

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.

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

WHAT 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 FAIRE 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 par
un installateur ou un service d’entretien qualifié ou
par le fournisseur de gaz.

AVERTISSEMENT

H2335500G

Page 2

LAARS Heating Systems

TABLE OF CONTENTS

SECTION 1.
General Information

1.1 Introduction...................................................... 4

1.2 Model Identification ......................................... 4

1.3 Appliance Overview......................................... 4

1.4 Warranty.......................................................... 9

1.5 Unpacking ....................................................... 9

1.6 Dimensions...................................................... 9

SECTION 2.
Locating the Appliance

2.1 Locating the Appliance .................................. 11

2.2 Locating Appliance for Correct Vent Distance

from Outside Wall or Roof Termination ......... 11

Section 3.
Venting and Combustion Air

3.1 Combustion Air .............................................. 12

3.1.1 Combustion Air From Room.......................... 12

3.1.2 Ducted Combustion Air ................................. 12

3.2 Venting .......................................................... 13

3.2.1 Venting Requirements Unique to Canada..... 14

3.3 Locating Vent & Combustion Air Terminals ... 14

3.3.1 Side Wall Vent Terminal................................ 14

3.3.2 Side Wall Combustion Air Terminal............... 15

3.3.3 Vertical Vent Terminal ................................... 15

3.3.4 Vertical Combustion Air Terminal .................. 15

3.3.5 Installations in the Commonwealth of

Massachusetts .............................................. 15

3.4 Common Vent Test ....................................... 17

Section 4.
Gas Supply and Piping

4.1 Gas Supply and Piping .................................. 18

Section 5.
Pump Requirements

5.1 NeoTherm Boiler Flow and

Head Requirements ...................................... 19

5.2 NeoTherm Water Heater

Flow and Head Requirements....................... 19

Section 6A.
Water Connections -

6A.1 NTH System Piping: Hot Supply Connections . 20

6A.2 NTH Cold Water Make-Up ............................ 20

6A.3 Freeze Protection .......................................... 21

6A.4 NTH Suggested Piping Schematics .............. 21

6A.5 Recognized Chemicals.................................. 21

NTH Boiler

Section 6B.
Water Connections -

6B.1 NTV Water Quality ........................................ 29

6B.2 Piping Requirements ..................................... 29

6B.3 Cold Water Make-Up..................................... 30

6B.4 Freeze Protection .......................................... 30

6B.5 NTV Suggested Piping Schematics............... 30

6B.6 NTV Suggested Pumps ................................. 30

NTV Water Heater

Section 7.
Electrical Connections

7.1 Main Power ................................................... 32

7.2 Pump Connections ........................................ 33

7.3 24 Vac Transformer with Integral

Circuit Breaker............................................... 33

7.4 Hydronic Call for Heat ................................... 33

7.5 Outdoor Air Temperature Sensor .................. 33

7.6 Domestic Hot Water Connection ................... 33

7.7 System Sensor

(lead lag/cascading operation only)............... 33

7.8 External Control Connections........................ 33

7.9 Optional Field Connections ........................... 33

7.10 Lead lag/ Cascading Wiring Connections ..... 33

7.11 Wiring Diagrams ............................................ 35

Section 8.
NeoTherm Control Setup and Operation

8.1 Display Navigation......................................... 37

8.2 Ignition Control - Sequence of Events ........... 37

8.3 Modulation Control ........................................ 38

8.4 Pump Control ................................................ 38

8.5 Anti-Short Cycle (ASC).................................. 38

8.5 High Limit ...................................................... 38

8.7 Outlet Water Temperature............................. 38

8.8 Inlet Water Temperature ............................... 38

8.9 Heat Exchanger Temperature Rise ............... 38

8.10 Stack Temperature........................................ 38

8.11 Domestic Hot Water Temperature................. 38

8.12 Lead Lag/Cascading ..................................... 38

8.12.1 Lead Lag Setpoint ......................................... 39

8.12.2 Lead Lag Master/Slave Selection.................. 39

8.12.3 Lead Lag Address ......................................... 39

8.12.4 Lead Lag Hysteresis...................................... 39

8.12.5 Lead Lag Base Load Setting ......................... 39

8.13 Boiler Pump Interrupt .................................... 39

NeoTherm Boilers and Water Heaters

Page 3

SECTION 9.
Modes of Operation

9.1 Hydronic Heating Demand ............................ 40

9.2 Hydronic Heating with Outdoor Reset ........... 40

9.3 Hydronic Heating with Domestic Hot

Water (DHW) Priority..................................... 40

9.4 Hydronic Heating Using External

Modulation Control ........................................ 40

9.5 Hydronic Heating Using Local Lead-Lag/

Cascading Feature........................................ 41

9.6 Hydronic Heating Using Local Lead-Lag/
Cascading Feature with Indirect Hot Water... 41

9.7 Warm Weather Shutdown ............................. 41

9.8 Domestic Hot Water Demand (NTV only)...... 41

9.9 Domestic Hot Water Heating Using

External Modulation Control .......................... 42

9.10 Domestic Hot Water Heating Using Local

Lead-Lag/Cascading Feature........................ 42

Section 10.
Operating Instructions

10.1 Filling the Boiler System ................................ 43

10.2 Operating the Burner and Set Up .................. 43

10.2.1 Burner Operation........................................... 43

10.2.2 Boiler Setup and Adjustment......................... 44

10.3 Shutting Down NeoTherm ............................. 44

10.4 To Restart NeoTherm.................................... 44

SECTION 11.
Maintenance

11.1 System Maintenance ..................................... 46

11.2 Appliance Maintenance and Component

Description .................................................... 46

11.2.1 Burner............................................................ 46

11.2.2 Modulating Gas Valve / Venturi ..................... 46

11.2.3 Appliance Control .......................................... 46

11.2.4 Ignitor Assembly............................................ 47

11.2.5 Flame Sensor ................................................ 47

11.2.6 Transformer with Integral Circuit Breaker...... 48

11.2.7 Blower ........................................................... 48

11.2.8 Heat Exchanger Coils.................................... 48

11.2.9 Gas Pressure Switches (optional) ................. 49

11.2.10 Gas Conversion ............................................. 49

Section 12.
Trouble Shooting

12.1 Sequence of Operation ................................. 49

12.2 Short Cycling ................................................. 49

12.3 Error Codes ................................................... 49

Section 13.
Replacement Parts

13.1 General Information....................................... 52

13.2 Parts List ....................................................... 52

Page 4

LAARS Heating Systems

SECTION 1.
General Information

WARNING

NeoTherm units must be installed in accordance with
the procedures detailed in this manual, or the LAARS
Heating Systems warranty will be voided. The
installation must conform to the requirements of the
local jurisdiction having authority, and, in the United
States, to the latest edition of the National Fuel Gas
Code, ANSI Z223.1/NFPA54. In Canada, the
installation must conform to the latest edition of CSA
B149.1 Natural Gas and Propane Gas Installation
Code, and/or local codes. Where required by the
authority having jurisdiction, the installation of
NeoTherm boilers must conform to the Standard for
Controls and Safety Devices for Automatically Fired
Boilers, ANSI/ASME CSD-1. Any modifications to the
boiler, its gas controls, or wiring may void the
warranty. If field conditions require modifications,
consult the factory representative before initiating
such modifications.

1.1 Introduction

This manual provides information necessary for
the installation, operation, and maintenance of LAARS
Heating Systems NeoTherm appliances. Read it
carefully before installation.

All application and installation procedures should
be reviewed completely before proceeding with the
installation. Consult the LAARS Heating Systems
factory, or local factory representative, with any
problems or questions regarding this equipment.
Experience has shown that most operating problems are
caused by improper installation.

NeoTherm is protected against over pressurization.
A pressure relief valve is included with each NeoTherm.
Some NeoTherms may require that the PRV be installed
prior to filling the system. Refer to Figures 1-7 for PRV
locations.

IMPORTANT: The inlet gas pressure to the appliance
must not exceed 13" W.C. (3.2kPa).

All installations must be made in accordance with

1) American National Standard Z223.1/NFPA54-Latest
Edition “National Fuel Gas Code” or 2) CSA B149.1
“Natural Gas and Propane Installation Code” and with
the requirement of the local utility or other authorities
having jurisdiction. Such applicable requirements take
precedence over the general instructions contained herein.

All electrical wiring is to be done in accordance
with the local codes, or in the absence of local codes,
with: 1) The National Electrical Code ANSI/NFPA No.
70-latest Edition, or 2) CSA STD. C22.1 “Canadian
Electrical Code - Part 1”. This appliance must be
electrically grounded in accordance with these codes.

1.2 Model Identification

Consult the rating plate on the unit. The following
information describes the model number structure.

(1-2) Model Series Designation

N T = NeoTherm

(3) Usage

H = Hydronic
V = Volume Water

(4-6) Size

0 8 0 = 80,000 BTU/hr input
1 0 5 = 105,000 BTU/hr input
1 5 0 = 150,000 BTU/hr input
1 9 9 = 199,000 BTU/hr input
2 1 0 = 210,000 BTU/hr input
2 8 5 = 285,000 BTU/hr input
3 9 9 = 399,000 BTU/hr input
5 0 0 = 500,000 BTU/hr input
6 0 0 = 600,000 BTU/hr input
7 5 0 = 750,000 BTU/hr input
8 5 0 = 850,000 BTU/hr input

(7) Fuel

N = Natural Gas
P = LP Gas

(8) Options Code

X = Standard Unit
J = CSD-1, FM, GAP, IL Code

(9) Pump Options

N = Pump included
X = No pump (configuration available for all sizes)

(10) Revision

2 = Second version

(80-500 only)

(size 500-850 only)

1.3 Appliance Overview

See Figures 1 through 7.

Model Nomenclature

12 3 456 7 8 9 10
NT H 2

SERIES

N T

USAGE

H - HYDRONIC
V - VOLUME

WATER

SIZE

MBTU/h

0 8 0
1 0 5
1 5 0
1 9 9
2 1 0
2 8 5
3 9 9
5 0 0
6 0 0
7 5 0
8 5 0

FUEL

N - NATURAL
P - PROPANE

OPTIONS CODE

X - STANDARD
J - CSD-1,

FM, GAP,

(500-850 only)

IL

PUMP OPTIONS

N - PUMP INCL.

(80-500 only)

X - NO PUMP

REVISION

2 - SECOND

NeoTherm Boilers and Water Heaters

Page 5

Figure 1. Location of Components, Sizes 80–105.

Figure 2. Location of Components, Sizes 150-210.

Page 6

LAARS Heating Systems

Figure 3. Location of Components, Size 285.

Figure 4. Location of Components, Size 399.

NeoTherm Boilers and Water Heaters

Page 7

Figure 5. Location of Components, Size 500.

Figure 6. Location of Components, Size 600.

Page 8

LAARS Heating Systems

Figure 7. Location of Components, Sizes 750 and 850.

NeoTherm Boilers and Water Heaters

Page 9

1.4 Warranty

LAARS Heating Systems’ NeoTherm appliances

are covered by a limited warranty. The owner should
complete the warranty registration at www.Laars.com.

All warranty claims must be made to an authorized
LAARS Heating Systems representative. Claims must
include the serial number and model (this information
can be found on the rating plate), installation date, and
name of the installer. Shipping costs are not included in
the warranty coverage.

Some accessory items may be shipped in separate
packages. Verify receipt of all packages listed on the
packing slip. Inspect everything for damage
immediately upon delivery, and advise the carrier of any
shortages or damage. Any such claims should be filed
with the carrier. The carrier, not the shipper, is

responsible for shortages and damage to the
shipment whether visible or concealed.

1.5 Unpacking

The NeoTherm is shipped in a single crate with the
following standard components packed with the
appliance (see Figure 8):

A. exhaust vent terminal

(US only)

B. air intake terminal

C. temperature/pressure gauge kit

D. circulator pump/wire harness

(units with pump)

E. CPVC exhaust pipe section (80-500) (US only)

F. outdoor/system sensor kit

G. flow switch kit

(399-850)

H. alternate size vent/terminal screens

J. exhaust vent adapter CPVC/ST ST

(750-850)

K. 4x6 PVC adapter with 4x7 PVC pipe section

(750-850) (not to be used on exhaust in Canada)

1. Remove all packing and tie-down materials.

2. Check contents of the carton against items shown.

1.6 Dimensions

Dimensions are shown in Figure 9.

Figure 8. Contents of Shipping Package.

Page 10

LAARS Heating Systems

W L H AIR INLET VENT

SIZE IN CM IN CM IN CM IN CM IN CM

80 25 64 19½ 49 38¼ 97 2 5.1 2 5.1
105 25 64 19½ 49 38¼ 97 2 5.1 2 5.1
150 25 64 19½ 49 38¼ 97 3 7.6 3 7.6

199/210 25 64 26¾ 68 38¼ 97 3 7.6 3 7.6

285 25 64 26¾ 68 38¼ 97 4½ 11 4½ 11
399 25 64 31½ 80 38¼ 97 4½ 11 4½ 11
500 25 64 37¾ 96 38¼ 97 4½ 11 4½ 11
600 25 64 37¾ 96 38¼ 97 4½ 11 4½ 11
750 25 64 51 130 38¼ 97 4½ 11 6½ 17
850 25 64 55¼ 130 38¼ 97 4½ 11 6½ 17

Dimensions are nominal and are shown in inches, cm.

NeoTherm is shipped with adapters for the air and vent that accept

*

standard pipe of the proper size and type.

AB CD E F G J K MN

SIZE IN CM IN CM IN CM IN CM IN CM IN CM IN CM IN CM IN CM IN CM IN CM

80 NTH 13½ 34 9½ 24 18¼ 46 7½ 19 10¾ 28 11¾ 30 13¾ 35 21 53 10¾ 27 15¼ 39 13 33
105 NTH 13½ 34 8 21 18¼ 46 6 16 10¾ 28 11¾ 30 14¼ 36 21 53 8¾ 22 15¼ 39 13 33
150 NTH 13¼ 34 5¼ 14 18¼ 46 3¼ 8 10¾ 28 7½ 19 14¼ 36 19½ 49 7½ 19 15¼ 39 13 33
150 NTV 13¼ 34 5¼ 14 19 48 3¼ 8 10¾ 28 7½ 19 14¼ 36 19½ 49 7½ 19 15¼ 39 13 33
210 NTH 20½ 52 5¼ 14 18¼ 46 3¼ 8 17¾ 45 7½ 19 14¼ 36 19½ 49 11¾ 30 15¼ 39 13 33
199 NTV 20½ 52 5¼ 14 19 48 3¼ 8 17¾ 45 7½ 19 14¼ 36 19½ 49 11¾ 30 15¼ 39 13 33
285 NTH 20¼ 52 7¼ 19 19¼ 49 6¼ 16 11¼ 29 13½ 34 14 36 15 38 17 43 18¾ 48 13 33
285 NTV 20¼ 52 7¼ 19 19¾ 50 4¼ 16 11¼ 29 13½ 34 14 36 15 38 17 43 18¾ 48 13 33
399 NTH 25 64 5¼ 13 19¼ 49 4¼ 11 14¾ 37 18½ 47 19¼ 49 16½ 42 21¾ 55 18¾ 48 13 33
399 NTV 25 64 5¼ 13 19¾ 50 4¼ 11 14¾ 37 18½ 47 19¼ 49 16½ 42 21¾ 55 18¾ 48 13 33
500 NTH 30¼ 77 5¼ 13 19½ 50 4¼ 11 15¼ 38 20 51 20½ 52 19 48 26 66 18¾ 48 13 33
500 NTV 30¼ 77 5¼ 13 19¾ 50 4¼ 11 15¼ 38 20 51 20½ 52 19 48 26 66 18¾ 48 13 33
600 (both) 29¾ 76 5 13 19½ 50 4¼ 11 15 38 20 51 3 8 19 48 26 66 18¾ 48 8¼ 21
750 (both) 35½ 90 6 15 19½ 50 5¼ 13 19 48 40½ 103 3¼ 8 19 48 30¾ 78 18¾ 48 8¼ 21

(both) 39¾ 101 6 15 19½ 50 5¼ 13 19 48 44¾ 114 3½ 9 19 48 35 89 18¾ 48 8¼ 21

850

Figure 9. Dimensional Drawing, Sizes 80-500.

NeoTherm Boilers and Water Heaters

SECTION 2.
Locating the Appliance

Page 11

2.1 Locating the Appliance

NeoTherm is for indoor installations only.

The appliance should be located to provide
clearances on all sides for maintenance and inspection.
It should not be located in an area where leakage of any
connections will result in damage to the area adjacent to
the appliance or to lower floors of the structure.

When such a location is not available, it is
recommended that a suitable drain pan, adequately
drained, be installed under the appliance.

The appliance is design certified by CSA­International for installation on combustible flooring; in
basements; in closets, utility rooms or alcoves.

NeoTherm Boilers must never be installed on
carpeting. The location for the appliance should be

chosen with regard to the vent pipe lengths and external
plumbing and on a level surface. The unit shall be
installed such that the gas ignition system components
are protected from water (dripping, spraying, rain, etc.)
during operation and service (circulator replacement,
control replacement, etc.). When vented vertically, the
NeoTherm must be located as close as practical to the
vertical section of the vent. If the vent terminal and/or
combustion air terminal terminate through a wall, and
there is potential for snow accumulation in the local
area, both terminals should be installed at an appropriate
level above grade or the maximum expected snow line.

The dimensions and requirements that are shown
in Table 1 should be met when choosing the locations
for the appliance.

2.2 Locating Appliance for Correct Vent

Distance from Outside Wall or

Roof Termination

The forced draft combustion air blower in the
appliance has sufficient power to vent properly when
the guidelines in Table 2 are followed.

NOTE: When located on the same wall, the NeoTherm
combustion air intake terminal must be installed a
minimum of 12" below the exhaust terminal.Models 399­850 also require a minimum horizontal distance from
intake to exhaust terminal of 36".

For concentric vent terminal kit (optional), follow
installation instructions included with the kit.

APPLIANCE
SURFACE INCHES CM

Left Side 1 2.5
Right Side 12 31
Top 24 61
Back 6 15
Closet, Front (285-500) 6 15
Alcove, Front (285-500) 24 61
Front (600-850) 24 61
Vent – –

Certified by CSA for zero clearance to

STANDARD MAX EQUIV. OPTIONAL MAX EQUIV.

SIZE VENT FT. M VENT FT. M

80 2" 40 6.1 3" 100 30.5
105 2" 40 6.1 3" 100 30.5
150 3" 100 30.5 n/a — —

199/210 3" 100 30.5 n/a — —

285 4" 100 30 n/a — —
399 4" 100 30 n/a — —
500 4" 100 30 n/a — —
600 4" 100 30 n/a — —
750 4" 40 6.1 6" 100 30
850 4" 40 6.1 6" 100 30

Installations in the U.S. require exhaust vent pipe that is a combination
of PVC & CPVC complying with ANSI/ASTM D1785 F441 or stainless
steel complying with UL1738. Installations in Canada require exhaust
vent pipe that is certified to ULC S636.

Intake (air) pipe must be PVC or CPVC that complies with ANSI/ASTM
D1785 F441, ABS that complies with ANSI/ASTM D1527 or

galvanized material.

Installer must comply fully with manufacturer's installation instructions,
including use of minimum exhaust length CPVC, to maintain ANSI
Z21.13 safety certification.

Closet and alcove installations do not allow the use of PVC under any
circumstances

To calculate max equivalent length, measure the linear feet of the
pipe, and add 5 feet (1.5m) for each elbow used.

SUGGESTED SERVICE ACCESS CLEARANCE

combustible materials on all sides.

Table 1. Clearances.

INTAKE / EXHAUST

Table 2. Vent / Air Pipe Sizes.

Page 12

LAARS Heating Systems

SECTION 3.
Venting and Combustion Air

3.1 Combustion Air

NeoTherm boilers and water heaters must have
provisions for combustion and ventilation air in
accordance with the applicable requirements for
Combustion Air Supply and Ventilation in the National
Fuel Gas Code, ANSI Z223 1; or in Canada, the Natural
Gas and Propane Installation Code, CSA B149.1. All
applicable provisions of local building codes must also
be adhered to.

A NeoTherm unit can take combustion air from
the space in which it is installed, or the combustion
air can be ducted directly to the unit. Ventilation air
must be provided in either case.

3.1.1 Combustion Air From Room

In the United States, the most common
requirements specify that the space shall communicate
with the outdoors in accordance with method 1 or 2,
which follow. Where ducts are used, they shall be of the
same cross-sectional area as the free area of the
openings to which they connect.

HORIZONTAL INTAKE AND EXHAUST PVC VENT TERMINAL KITS

2" PVC 3" PVC 4" PVC 6" PVC

SIZE

105 included optional optional optional n/a n/a
150 n/a n/a included optional n/a n/a

199/ 210 n/a n/a included optional n/a n/a

285 n/a n/a optional optional included n/a
399 n/a n/a n/a n/a included n/a
500 n/a n/a n/a n/a included n/a
600 n/a n/a n/a n/a included optional
750 n/a n/a n/a n/a n/a included
850 n/a n/a n/a n/a n/a included

Concentric vent terminal = 10 ft. pipe length.

Standard Concentric Standard Concentric Standard Standard

CA006000 CA005900 239-44069-01

80 included optional optional optional n/a n/a

Table 3a. PVC Vent Terminal Kits.

Method 1: Two permanent openings, one

commencing within 12" (300mm) of the top and one
commencing within 12" (300mm) of the bottom, of the
enclosure shall be provided. The openings shall
communicate directly, or by ducts, with the outdoors or
spaces that freely communicate with the outdoors.
When directly communicating with the outdoors, or
when communicating to the outdoors through vertical
ducts, each opening shall have a minimum free area of 1
square inch per 4000 Btu/hr (550 square mm/kW) of
total input rating of all equipment in the enclosure.
When communicating to the outdoors through
horizontal ducts, each opening shall have a minimum
free area of not less than 1 square inch per 2000 Btu/hr
(1100 square mm/kW) of total input rating of all
equipment in the enclosure.

Method 2: One permanent opening, commencing

within 12" (300mm) of the top of the enclosure, shall be
permitted. The opening shall directly communicate with
the outdoors or shall communicate through a vertical or
horizontal duct to the outdoors or spaces that directly
communicate with the outdoors and shall have a
minimum free area of 1 square inch per 3000 Btu/hr
(734 square mm/kW) of the total input rating of all
equipment located in the enclosure. This opening must
not be less than the sum of the areas of all vent
connectors in the confined space.

Other methods of introducing combustion and
ventilation air are acceptable, providing they conform to
the requirements in the applicable codes listed above.

In Canada, consult local building and safety codes or,
in absence of such requirements, follow CAN/CGA B149.

3.1.2 Ducted Combustion Air

The combustion air can be taken through the wall, or
through the roof. When taken from the wall, it must be
taken from out-of-doors by means of the LAARS
horizontal wall terminal, shown in Table(s) 3. See Table 2
to select the appropriate diameter air pipe. When taken
from the roof, a field-supplied rain cap or an elbow
arrangement must be used to prevent entry of rain water
(see Figure10).

SIZE Boiler Flue Intake Air Boiler Intermediate Flue Intake Air Boiler Flue Intake Air

399-600 F303759
750-850

MATERIAL UNITED STATES CANADA

ABS ANSI/ASTM D1527

PVC, sch 40 ANSI/ASTM D1785 or D2665

CPVC, sch 40 ANSI/ASTM F441

Single wall galv. steel 26 gauge

PRO TECH (FasNSeal) HEAT FAB (Saf-T-Vent) Z FLEX (Z-Vent)

Adapter Termination Termination Adapter Adapter Termination Termination Adapter Termination Termination

F303759

(intake only)

FSBS4 FSAIH04

FSRC4(R.C) 303888 5400CI 2SVSRCX04

FSBS6

FSAIH04

303888 Table 3b. Approved Stainless Steel Terminations and Adapters.

Table 4. Required Combustion Air Pipe Material.

KB285600 9454BUREZ-1*

INSTALLATION STANDARDS

9492

9414TERM 2SVSLA04

Air pipe material must be chosen

based upon the intended application of the boiler.

2SVSTP04

2SVSTEX0490

NeoTherm Boilers and Water Heaters

Page 13

Use ABS, PVC, CPVC or galvanized pipe for the
combustion air intake (see Table 4), sized per Table 2.
Route the intake to the boiler as directly as possible. Seal
all joints. Provide adequate hangers. The unit must not
support the weight of the combustion air intake pipe.
Maximum linear pipe length allowed is shown in Table 2.
Subtract 5 allowable linear ft. (1.5m) for every elbow used.

The connection for the intake air pipe is at the top of
the unit (see Figure 9a or Figure 9b).

In addition to air needed for combustion, air shall
also be supplied for ventilation, including air required for
comfort and proper working conditions for personnel.

3.2 Venting

WARNING

Failure to use CPVC or stainless steel venting for the
first 20" (285-600) / 30" (80-210) of vent material or for
any part of the venting that is installed inside a closet
may lead to property damage, personal injury or death.
The proper length of this material is supplied with boiler.
Boilers in U.S. may use pipe included with boiler.

WARNING

Failure to use the appropriate vent material, installation
techniques, glues/sealants could lead to vent failure
causing property damage, personal injury or death.

The unit’s vent can terminate through the roof, or

through an outside wall.

When using PVC/CPVC for vent material, venting
must be connected to the CPVC section included with
NeoTherm sizes 80-600. The CPVC vent section
included with the NeoTherm may be broken by CPVC
fittings if necessary, but never reduced in total length.
See Table 2 to select the appropriate vent pipe diameter.
Vent pipe must pitch upward, toward the vent terminal,
not less than 1/4" per foot, so that condensate will run
back to the NeoTherm to drain. Route vent pipe to the
heater as directly as possible. Seal all joints and provide
adequate hangers as required in the venting system
manufacturer’s Installation Instructions. Horizontal
portions of the venting system must be supported to
prevent sagging and may not have any low sections that
could trap condensate. The unit must not support the
weight of the vent pipe. Please see Table 2 for proper
diameter vs. length allowed.

IMPORTANT NOTE ABOUT COMMON VENTING: A
single vent that is shared by multiple NeoTherm units
MUST be engineered by a competent venting
specialist, and involves the selection of draft inducing
equipment, hardware and controls to properly balance
flue gas pressures. Do not common vent NeoTherm

WARNING

All venting must be installed according to this manual
and any other applicable local codes, including but not
limited to, ANSI Z223.1/NFPA 54, CSA B149.1,
CSAB149.2 and ULC-S636. Failure to follow this
manual and applicable codes may lead to property
damage, severe injury, or death.

The flue temperature of the NeoTherm changes
dramatically with changes in operating water
temperature. Therefore, it is necessary to assess the
application of the boiler to determine the required
certified vent class. If the NeoTherm is installed in
an application where the ambient temperature is
elevated, and/or installed in a closet/alcove, CPVC or
stainless steel material is required. If the system
temperatures are unknown at the time of
installation, class IIB or higher venting material is
recommended.

The NeoTherm is a Category IV appliance and
may be installed with PVC and CPVC that complies
with ANSI/ASTM D1785 F441, or a stainless steel
venting system that complies with UL 1738 Standard
(see Table 5).

Figure 10. Combustion Air and Vent Through Roof.

INSTALLATION STANDARDS

MATERIAL UNITED STATES CANADA

Stainless Steel UL 1738

PVC, sch 40 ANSI/ASTM D178 venting material. The venting material must be chosen

CPVC, sch 40 ANSI/ASTM F441

Table 5. Required Exhaust Vent Material.

Venting must be ULC-S636 certified for use as

based upon the intended application of the boiler.

Page 14

LAARS Heating Systems

units unless the vent system meets this
requirement. NeoTherm units are never permitted
to share a vent with Category I appliances.

A condensate drain trap is built into NeoTherm.

Connect a 3/4" PVC pipe between the drain
connection and a floor drain (or condensate pump if a
floor drain is not accessible).

The condensate drain must be installed so as to
prevent accumulation of condensate. When a con­densate pump is not used, the tubing must continuously
slope downward toward the drain with no spiraling.

Consult local codes for disposal method.

Caution

Condensate is mildly acidic (pH
some floor drains and/or pipes, particularly those that
are metal. Ensure that the drain, drainpipe, and
anything that will come in contact with the
condensate can withstand the acidity, or neutralize
the condensate before disposal. Damage caused by

failure to install a neutralizer kit or to adequately
treat condensate will not be the manufacturer’s
responsibility.

..

.5), and may harm

..

3.2.1 Venting Requirements Unique to
Canada

NeoTherm boilers and water heaters are Vent
Category IV appliances. Per the requirements of CAN/
CSA-B149.1, only BH vent systems can be connected to
these units and such vent systems, either ULC S636
certified stainless steel or other ULC S636 certified BH
vent (eg. plastics) must be installed per the vent
manufacturer's certified installation instructions.

As a result, two items listed in the Unpacking
section (Figure 8) are

not included with NeoTherm

units for Canada (underlined):

A. exhaust vent terminal (not included)

B. air intake terminal

C. temperature/pressure gauge kit

D. circulator pump/wire harness (units with pump)

E. CPVC exhaust pipe section (80-500) (not incl.)

F. outdoor/system sensor kit

G. flow switch kit (399-850)

H. alternate size vent/terminal screens

J. exhaust vent adapter CPVC/ST ST (750-850)

It is the responsibility of the appropriately licensed
technician installing this NeoTherm unit to use ULC
S636 certified vent material consistent with the
requirements as described in the Venting and
Combustion Air section.

IMPORTANT! It is also the responsibility of the
installer to ensure that a flue gas sampling port is
installed in the vent system. This flue gas sampling port
must be installed near the flue connection of the
NeoTherm unit: within 2 feet of the flue connection.
There is no flue gas sampling port internal to the

NeoTherm, so one must be installed in the vent system
external to the NeoTherm unit. A flue gas sampling port
available as a component of the ULC S636 certified
vent system is preferred. However, if one is not
available with the certified vent system, Laars suggests
using a tee with the branch connection sized to allow for
insertion of a flue gas analyzer probe. The branch
connection must be resealable with a cap or other by
other means to ensure the vent system remains sealed

(Figure 11).

Consideration must be given to the placement and
orientation of the flue gas sampling port to ensure that
condensate is free to flow back into the NeoTherm unit
and not collect anywhere in the vent system - including
in the flue gas sampling port.

An exhaust vent terminal must be installed. If an
exhaust vent terminal is not available with the certified
vent system, Laars suggests the use of a coupler fitting
from the certified vent system into which the vent
terminal screen, included with the NeoTherm and
shown in the Unpacking section of the NeoTherm
Installation & Operating Instructions, be installed. Be
sure to install and terminate both vent and combustion
air pipes per the Venting and Combustion Air section of
the NeoTherm instructions.

3.3 Locating Vent & Combustion Air

Terminals

3.3.1 Side Wall Vent Terminal

The appropriate Laars side wall vent terminal must
be used. The terminal must be located in accordance
with ANSI Z223.1/NFPA 54 and applicable local codes.
In Canada, the installation must be in accordance with
CSA B149.1 or .2 and local applicable codes. Consider
the following when installing the terminal:

Figure 11. Test Port.

NeoTherm Boilers and Water Heaters

Page 15

1. Figure 12 shows the requirements for mechanical
vent terminal clearances for the U.S. and Canada.

2. Vent terminals for condensing appliances or
appliances with condensing vents are not
permitted to terminate above a public walkway, or
over an area where condensate or vapor could
create a nuisance or hazard.

3. Locate the vent terminal so that vent gases cannot
be drawn into air conditioning system inlets.

4. Locate the vent terminal so that vent gases cannot
enter the building through doors, windows, gravity
inlets or other openings. Whenever possible, avoid
locations under windows or near doors.

5. Locate the vent terminal so that it cannot be

blocked by snow. The installer may determine
that a vent terminal must be higher than the
minimum shown in codes, depending upon local
conditions.

6. Locate the terminal so the vent exhaust does not
settle on building surfaces or other nearby objects.
Vent products may damage surfaces or objects.

7. If the boiler or water heater uses ducted
combustion air from an intake terminal located on
the same wall, see Figures 12-14 for proper
spacing and orientation.

If the vent termination is located in an area

exposed to high winds, an optional PVC tee (the same
diameter as the vent pipe) may be used. The tee'd vent
termination offers greater protection from wind related
operating issues.

3.3.2 Side Wall Combustion Air Terminal

The LAARS side wall combustion air terminal, or

concentric terminal (see Table 3), must be used when
the heater takes air from a side wall. Contact Laars for
AL29-4C termination fittings. Consider the following
when installing the terminal (see Figures 12-14):

1. Do not locate the air inlet terminal near a source of
corrosive chemical fumes (e.g., cleaning fluid,
chlorine compounds, etc.)

2. Locate the terminal so that it will not be subject to
damage by accident or vandalism. It must be at
least 7 feet (2.1m) above a public walkway.

3. Locate the combustion air terminal so that it
cannot be blocked by snow. The National Fuel Gas
Code requires that it be at least 12 inches (30cm)
above grade, but the installer may determine it
should be higher, depending upon local conditions.

4. If the NeoTherm is side-wall vented to the same
wall, locate the vent terminal at least 1 foot (0.3m)
above the combustion air terminal.

5. For concentric vent, follow instructions

included with vent kit.

6. Multiple vent kits should be installed such that the
horizontal distance between outlet group and inlet
group is 36" (90cm) (see Figure 13).

7. Vent outlet for models 80-285 must be no lower
than the center of the air inlet, and must be at least

12" (30cm) away from the air inlet. Vent outlets
for models 399-850 must be at least 12" above the
top of the air inlet, and must be at least 36" (90cm)
horizontally from the air inlet (see Figure 14).

3.3.3 Vertical Vent Terminal

When the unit is vented through the roof, the vent
must extend at least 3 feet (0.9m) above the point at
which it penetrates the roof. It must extend at least 2
feet (0.6m) higher than any portion of a building within
a horizontal distance of 10 feet (3.0m), and high enough
above the roof line to prevent blockage from snow. The
vent terminal included with the NeoTherm can be used
in both vertical and horizontal applications. When the
combustion air is taken from the roof, the combustion
air must terminate at least 12" (30cm) below the vent
terminal (see Figure 11).

3.3.4 Vertical Combustion Air Terminal

When combustion air is taken from the roof, a
field-supplied rain cap or an elbow arrangement must be
used to prevent entry of rain water (see Figure 11). The
opening on the end of the terminal must be at least 12"
(30cm) above the point at which it penetrates the roof,
and high enough above the roof line to prevent blockage
from snow. When the vent terminates on the roof, the
combustion air must terminate at least 12" (30cm)
below the vent terminal.

3.3.5 Installations in the Commonwealth of
Massachusetts

In Massachusetts the following items are required if
the side-wall exhaust vent termination is less than seven (7)
feet above finished grade in the area of the venting,
including but not limited to decks and porches. From
Massachusetts Rules and regulations 248 CMR 5.08

1. Installation of Carbon Monoxide Detectors

At the time of installation of the side wall vented
gas fueled appliance, the installing plumber or gas­fitter shall observe that a hard-wired carbon monox­ide detector with an alarm battery back-up is instal­led on the floor level where the gas appliance is to
be installed. In addition, the installing plumber or
gasfitter shall observe that a battery operated or
hard-wired carbon monoxide detector with an alarm
is installed on each additional level of the dwelling,
building or structure served by the side-wall hori­zontally vented gas fueled equipment. It shall be the
responsibility of the property owner to secure the
services of qualified licensed professionals for in­stallation of hard-wired carbon monoxide detectors.
a. In the event that the side-wall horizontally vented
gas fueled equipment is installed in a crawl space or
an attic, the hard-wired carbon monoxide with alarm
and battery back-up may be installed on the next
adjacent floor level.
b. In the event that the requirements of the subdivi­sion cannot be met at the time of completion of
installation, the owner shall have a period of thirty

Page 16

U.S. Installations (see note 1) Canadian Installations (see note 2)

A= Clearance above grade, veranda, porch, 12 inches (30 cm) 12 inches (30 cm)

deck, or balcony See note 6 See note 6

B= Clearance to window or door that may be Direct vent only: 12 inches (30cm); 36 inches (91 cm)

opened Other than Direct vent: 4 ft (1.2m) below or to

side of opening; 1 ft (30cm) above opening

C= Clearance to permanently closed window See note 4 See note 5
D= Vertical clearance to ventilated soffit located

above the terminal within a horizontal See note 4 See note 5
distance of 2 feet (61cm) from the center
line of the terminal

E= Clearance to unventilated soffit See note 4 See note 5
F= Clearance to outside corner See note 4 See note 5
G= Clearance to inside corner See note 4 See note 5
H= Clearance to each side of center line 3 feet (91 cm) within a height 15 feet

extended above meter/regulator assembly See note 4 above the meter/regulator assembly

I= Clearance to service regulator vent outlet See note 4 3 feet (91 cm)
J= Clearance to nonmechanical air supply Direct vent only: 12" (30cm) 80-285; 36" (91cm)

inlet to building or the combustion air inlet 399-850. Other than Direct vent: 4 ft (1.2m) below 36 inches (91 cm)
to any other appliance or to side of opening; 1 ft (30cm) above opening

K= Clearance to a mechanical air supply inlet 3 feet (91 cm) above if within 10 feet (3 m) 6 feet (1.83 m)

horizontally

L= Clearance above paved sidewalk or paved Vent termination not allowed in this location Vent termination not allowed in this

driveway located on public property for category IV appliances. location for category IV appliances.

M= Clearance under veranda, porch, deck, See note 4 12 inches (30 cm) (see note 3)

or balcony

Notes:

1. In accordance with the current ANSI Z223.1 / NFPA 54 National Fuel Gas Code.

2. In accordance with the current CAN/CGA-B149 Installation Codes.

LAARS Heating Systems

3. Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.

4. For clearances not specified in ANSI Z223.1 / NFPA 54, clearance is in accordance with local installation codes and the requirements of the
gas supplier.

5. For clearances not specified in CAN/CGA-B149, clearance is in accordance with local installation codes and the requirements of the gas
supplier.

6. IMPORTANT: terminal must be placed such that it remains a minimum 12" above expected snow line. Local codes may have more
specific requirements, and must be consulted.

Figure 12. Combustion Air and Vent Through Side Wall.

*When vent terminal is less than 10 feet (3m) horizontally
from a forced air inlet, the terminal must be at least 3 feet
(0.9m) above the air inlet.

NeoTherm Boilers and Water Heaters

Figure 13. Multiple Side-Wall Terminals, Air and Vent.

(30) days to comply with the above requirements,
provided, however, that during said thirty (30) day
period, a battery operated carbon monoxide detector
with an alarm be installed.

2. Approved Carbon Monoxide Detectors

Each carbon monoxide detector shall comply with
NFPA 720 and be ANSI/UL 2034 listed and IAS
certified.

3. Signage

A metal or plastic identification plate shall be
permanently mounted to the exterior of the building
at a minimum height of eight (8) feet above grade
directly in line with the exhaust vent terminal for
horizontally vented gas fueled heating appliance or

Page 17

equipment. The sign shall read, in print no less than
one-half (1/2) inch in size: "GAS VENT DI­RECTLY BELOW, KEEP CLEAR OF ALL
OBSTRUCTIONS".

4. Inspection

The state or local gas inspector of the side-wall
horizontally vented gas fueled appliance shall not
approve the installation unless, upon inspection, the
inspector observes carbon monoxide detectors and
signage installed in accordance with the provisions
of 248 CMR 5.08(2)(a) 1-4.

3.4 Common Vent Test

NOTE: This section does not describe a method for

common venting NeoTherm units. It describes what
must be done when a unit is removed from a common
vent system. NeoTherm units require special vent
systems and fans for common vent. Contact the factory
if you have questions about common venting
NeoTherm units.

When an existing boiler is removed from a
common venting system, the common venting system is
likely to be too large for proper venting of the
appliances remaining connected to it.

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 openings 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

Figure 14. Minimum Venting Distance.

Page 18

LAARS Heating Systems

deficiencies which could cause an unsafe condition.

3. Insofar as it 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 the 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 that the installation
conforms to the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 and/or CSA B149.1, Installation
Codes. When resizing any portion of the common
venting system, the common venting system should
be resized to approach the minimum size as deter­mined using the appropriate tables and guidelines in
the National Fuel Gas Code, ANSI Z223.1 NFPA
54 and/or CSA B149.1, Installation Codes.

SECTION 4.
Gas Supply and Piping

4.1 Gas Supply and Piping

Gas piping should be supported by suitable

hangers or floor stands, not the appliance.

Review the following instructions before

proceeding with the installation.

1. Verify that the appliance is fitted for the proper type of
gas by checking the rating plate. NeoTherm will
function properly without the use of high altitude
modification at elevations up to 10,000 feet (3050 m).

2. The maximum inlet gas pressure must not exceed
13" W.C. (3.2kPa). The minimum inlet gas
pressure is 4" W.C. (1.0kPa).

3. Refer to Tables 6A, 6B, 6C and 6D to size piping.

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

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

6. A sediment trap must be provided upstream of the
gas controls.

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

8. The appliance and its individual shutoff valve
must be disconnected from the gas supply piping
during any pressure testing of that system at test
pressures in excess of 1/2 PSIG (3.45kPa).

9. The unit must be isolated from the gas supply
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
1/2 PSIG (3.45kPa).

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

11. Purge all air from gas lines.

WARNING:

Open flame can cause gas to ignite and result in
property damage, severe injury, or loss of life.

NOTE: The NeoTherm appliance and all other gas
appliances sharing the gas supply line must be firing at
maximum capacity to properly measure the inlet supply
pressure. The pressure can be measured at the supply
pressure port on the gas valve. Low gas pressure could
be an indication of an undersized gas meter, undersized
gas supply lines and/or an obstructed gas supply line.
Some NeoTherm units are equipped with low and high
gas pressure switches that are integrally vent limited.
These types of devices do not require venting to
atmosphere.