Lennox GWM-050IE User manual

PN# 240009475, Rev. C [03/2014]
RETAIN THESE INSTRUCTIONS FOR
FUTURE REFERENCE
These instructions must be afxed
on or adjacent to the boiler.
WALL MOUNTED GAS
BOILER
INSTALLATION
INSTRUCTIONS
PRODUCT LITERATURE
Lennox Industries Inc.
Dallas, Texas
WALL MOUNTED GAS-FIRED HOT WATER
BOILERS
TheseGas-FiredWaterboilersarelowpressure,
stainless steel boilers Design Certied by CSA
(Canadian Standards Association) for use with
Natural and Propane Gases. They are constructed
and hydrostatically tested for a maximum working
pressure of 50 psi (pounds per square inch) in
accordance with A.S.M.E. (American Society
of Mechanical Engineers) Boiler and Pressure
Vessel Code Section IV Standards for Heating
Boilers.
GWM-050IE, GWM-075IE,
GWM-100IE, GWM-150IE,
GWM-200IE,
WARNING
Improper installation, adjustment, alteration, service,
or maintenance could result in death or serious injury.
Refer to this manual for assistance. For additional
information consult a qualied installer, service
agency, or the gas supplier.

2
Description
Item No. Illustration
Fully Assembled Boiler 1
Metal Wall Bracket 2
Lag Bolt, 3/8" x 3" Hex (4 ea) 3
*Safety Relief Valve 4
3/4" Tee 5
3/4" Nipple 6
3/4" x 1/4" Elbow 7
Air Vent 8
**Temperature Pressure Gauge 9
Bushing 3/4" x 1/4" 10
3/4" Tee (Same as No. 11) 11
Nipple 1¼ x 5½ 12
Drain Valve, 3/4" 13
3/4" Tee 14
Nipple 1¼ x 5½ 15
Bushing 7/8" OD, Heyco (2 ea) 16 Used for electrical wire knockouts.
Stopper, Rubber 5/16" (2 ea) 17 Used for packaging holes on back of boiler.
Plastic Plug (2 ea) 18 Used for packaging holes on back of boiler.
Outdoor Sensor 19 Used for measuring outside temperature.
Critical Installation Instruction 20 11" x 17" Page for critical installation issues.
Document Package 21 Includes essential documents.
4
5
6
7
8
2
3
9
10
12
13
14
11
15
VERIFY CONTENTS RECEIVED
* Boiler provided with 30 psig (206 kpa) safety relief valve. Field source safety relief valve if system pressure
greater than 25 psig.
** Boiler provided with 75 psig temperature pressure gauge. Field source temperature pressure gauge if system
pressure greater than 60 psig.

3
(C)
DIMENSIONS
FIGURE 1-1 Dimensions
(D)
Wall Hanging
Bracket
(D)
(A)
(E)
Vent Connector
Combustion Air
Safety Relief
Valve
Connection
(¾ NPT)
(B)
Condensate Drain Connection (L)
Return Water (F)
Supply Water (F)
Gas Connection (K)
(G)
(J)
Table 1 : Physical Data
Models 050/075/100 150/200
Width (A) 20" (508mm) 23" (584mm)
Height (B) 30" (762mm) 40" (1041mm)
Depth (C) 14" (356mm)
16.0"
(406mm)
Bracket (D) 28" (711mm) 40" (1016mm)
Height (E) 31" (787mm) 42" (1092mm)
Water
Connections
Size(F) 1-1/4" NPT
1-1/4" NPT
Location (G) 2" (51mm) 2" (51mm)
Location (H) 5" (127mm)
2" (51mm)
Location (I) 3" (76mm)
4-½" (114mm)
Gas
Connection Location (J) 4-1/2" (114mm) 4-1/2" (114mm)
Size (K) 1/2"
NPT
3/4"
NPT
Condensate Drain
Connection (L) 3/4" NPT
3/4" NPT
Weight Shipping 111 lb (50 kg) ~182 lb
(83 kg)
Unit 91 lb (41 kg) ~157 lb
(71 kg)
Vent Connector 2" (51mm) 3" (76mm)
(H) (I)
DIMENSIONS

4
1 - Introduction............................................................................................................................... 5
2 - Important Safety Information.................................................................................................... 6
3 - Component Listing ..................................................................................................................... 7
4 - Locating Boiler......................................................................................................................... 11
5 - Hydronic Piping........................................................................................................................ 13
5.2 Special Conditions................................................................................................................. 13
5.3 Safety Relief Valve and Air Vent............................................................................................ 13
5.4 Trim Piping........................................................................................................................... 14
5.5 System Piping....................................................................................................................... 14
6 - Combustion Air And Vent Piping............................................................................................... 21
6.2 Removal of Existing Boiler From Common Vent System........................................................... 21
6.3 Venting Materials ................................................................................................................. 21
6.4 Vent Pipe Installation............................................................................................................. 22
6.5 Vent Termination .................................................................................................................. 22
6.6 Venting Congurations........................................................................................................... 23
6.7 Side Venting Terminal Requirements..........................................................................................28
6.8 Multiple Boiler Venting Installation............................................................................................30
6.9 Condensate Piping................................................................................................................. 31
7 - Gas Supply Piping .................................................................................................................... 32
8 - Electrical Connections.............................................................................................................. 34
8.3 Line Voltage Connections ....................................................................................................... 34
8.4 External Connections............................................................................................................. 34
9 - Start Up Procedure................................................................................................................... 36
9.6 Perform CSD-1 Compliance Test ......................................................................................................40
9.7 Complete Start Up Procedure.................................................................................................. 41
10 - Operating Instructions........................................................................................................... 42
11 - General Maintenance And Cleaning ........................................................................................ 43
12 - Ratings And Capacities........................................................................................................... 46
13 - Trouble Shooting.................................................................................................................... 47
14 - Wiring Diagram...................................................................................................................... 65
15 - Glossary................................................................................................................................. 68
Appendix A - Control Module ......................................................................................................... 70
1.1 Introduction ......................................................................................................................... 70
1.2 Operation............................................................................................................................. 70
1.3 Status Indication................................................................................................................... 70
1.4 Sequence of Operation........................................................................................................... 71
1.5 User Menu ........................................................................................................................... 73
TABLE OF CONTENTS

5
1.1 Designated Use
• Hot water heating boiler.
• Indoor installation.
• Closet or alcove installation.
• Direct vent boiler.
• For use with natural gas or liqueed petroleum gases
(LP/propane).
1.2 The unit MUST NOT:
• Directly heat potable water. Indirect heating is acceptable.
• Heat water with non-hydronic heating system chemicals
present (example, swimming pool water).
• Exceed 150 psig (1.03 MPa) maximum allowable
working pressure.
• Exceed 195°F (90.5°C) system design temperature.
1.3 Operational Features
• Modulating: 20-100%.
• Integral Dual Limit.
• Integral Low Water Cutoff (with test button).
• Outdoor Temperature Reset.
• Integral Multiple Boiler Control.
Information and specications outlined in this manual in effect at the
time of printing of this manual. ManufacturerManufacture reserves the right to
discontinue, change specications or system design at any time without
notice and without incurring any obligation, whatsoever.
1 - INTRODUCTION

6
2.3 Installation shall conform to requirements of
authority having jurisdiction or in absence of such
requirements:
• United States
• National Fuel Gas Code, ANSI Z223.1/NFPA 54 .
• National Electrical Code, NFPA 70.
• Canada
• Natural Gas and Propane Installation Code,
CAN/CSA B149.1.
• Canadian Electrical Code, Part I, Safety Standard
for Electrical Installations, CSA C22.1
2.4 Where required by authority having jurisdiction,
installation shall conform to Standard for Controls
and Safety Devices for Automatically Fired Boilers,
ANSI/ASME CSD-1.
Additional manual reset low water cutoff may be required.
2.5 Requirements for Commonwealth of
Massachusetts:
Boiler installation must conform to Commonwealth of
Massachusetts code 248 CMR which includes but is not
limited to: Installation by licensed plumber or gas tter.
NOTICE
Used to address practices not related to personal
injury.
CAUTION
Indicates a hazardous situation which, if not avoided,
could result in minor or moderate injury.
!
WARNING
Indicates a hazardous situation which, if not avoided,
could result in death or serious injury.
!
DANGER
Indicates a hazardous situation which, if not avoided,
WILL result in death or serious injury
!
This is the safety alert symbol. Symbol alerts you to
potential personal injury hazards. Obey all safety messages
following this symbol to avoid possible injury or death.
2.2 Become familiar with symbols identifying
potential hazards.
2.1 General
Boiler installation shall be completed by qualied agency.
See glossary for additional information.
WARNING
Fire, explosion, asphyxiation and electrical shock
hazard. Improper installation could result in death or
serious injury. Read this manual and understand all
requirements before beginning installation.
!
2 - IMPORTANT SAFETY INFORMATION

7
3.1 Component Listing - Refer to diagrams on
following pages.
1. User Interface Displays information regarding boiler
condition. Allows adjustment of boiler operating
parameters. NOTE: Does not replace thermostat used
to control central heating space.
2. Combustion Air Inlet (2"/3") See section 6.
3. Return Water From Heating System (In)
Connection supplied at bottom of boiler. See section 5.
4. Low Voltage Terminal Strip Connection of all low
voltage wiring, including thermostat.
5. Igniter
6. Flame Sensor
7. Sight Glass Permits observation of burner ame.
8. Burner (see page 40)
9. Heat Exchanger
10. Condensate Collector
11. Return Water Temperature Sensor
12. Drain Valve (see page 14)
13. Internal Primary Loop Ball Valve
14. Supply Water Outlet to Heating System (Out)
Connections supplied for connecting from bottom of
boiler. See section 5.
15. Vent Temperature Sensor
16. Condensate Drain Boiler produces a liquid
(condensate) as a by-product of combustion. Condensate
must be piped to appropriate drain. See section 6.
17. Heat Exchanger Pump
18. Gas Shutoff Valve Fuel supply isolation during
servicing. See section 7
19. Combustion Air Blower Delivers proper quantity of
combustion air, receives fuel from gas valve, mixes air
and fuel sending mixture to burner for combustion.
20. Gas (Control) Valve Delivers proper quantity of fuel
to Combustion Air Blower. See section 7.
21. Supply Water Temperature Sensor and High Limit
Switch
22. Low Water Cutoff Senses inadequate quantity of
water. Turns off boiler before damage can occur.
23. Safety Relief Valve Factory supplied, Field installed.
See section 5.
24. High Voltage Junction Box For connection of 120V
components. See section 8.
25. Vent Connector See section 6.
26. Gas Connection See section 7.
27. Wall Hanging Support Bracket (see page 12)
Integral to boiler. Allows wall mounting when used
with supplied wall mounting bracket. See section 4.
28. Air Vent
29. Boiler Control Module
30. Lower Jacket Panel Gently pull upward then forward
to access.
31. Transformer Supplies 24V power to low water cutoff.
32. Flue Air Mixture Pressure Test Port - Not available
on all models.
33. Combustion Analysis Test Port
34. Internal Pump Relay - Not available on all models.
35. Heat Exchanger Surface Temperature Switch
36. ASME Plate
3 - COMPONENT LISTING

8
FIGURE 3-1 Boiler Components (Viewed from Back of Boiler)
VENT CONNECTOR
NOTE:
See Section 5-3 For
Safety Relief Valve
Piping Instructions
COMBUSTION
AIR INLET
SAFETY RELIEF VALVE
AIR VENT
FIGURE 3-2 Upper and Lower Jacket Latch (Viewed
from front of boiler)
Lift Jacket up,
engage jacket with
chassis,
push down.
Upper and Lower
Jacket Latch
WALL MOUNT
SUPPORT
BRACKET
3 - COMPONENT LISTING

9
FIGURE 3- Boiler Components 50/75/100 MBH (View from Front of Boiler) As seen on front cover
(18) GAS SHUTOFF
VALVE
(SHOWN IN OPEN
POSITION)
(25) VENT CONNECTOR
(19) COMBUSTION
AIR
BLOWER
(20) GAS (CONTROL)
VALVE
(22) LOW
WATER CUTOFF
(23) SAFETY RELIEF VALVE
(28) AIR VENT
(2) COMBUSTION
AIR INLET
NOTE:
See Section 5
For Piping
Instructions
(17) HEAT EXCHANGER
PUMP
(10) CONDENSATE
COLLECTOR
(3) RETURN WATER
FROM HEATING
SYSTEM (IN)
(14) SUPPLY WATER TO
HEATING SYSTEM (OUT)
(4) LOW VOLTAGE
TERMINAL STRIP
(15) VENT
TEMPERATURE
SENSOR
(26) GAS CONNECTION
(33) COMBUSTION
ANALYSIS TEST
PORT
(24) HIGH VOLTAGE
JUNCTION BOX
(9) HEAT
EXCHANGER
(29) BOILER
CONTROL
MODULE
Fuse and
Holder
(5) IGNITER
(6) FLAME
SENSOR
(7) SIGHT GLASS
(32) FLUE
AIR MIXTURE
PRESSURE
TEST PORT
(16) CONDENSATE
DRAIN
(7) SIGHT GLASS
(7) SIGHT GLASS
(33) COMBUSTION
(33) COMBUSTION
(15) VENT
TEMPERATURE
(31) TRANSFORMER
(6) FLAME
(1) USER INTERFACE
(11) RETURN WATER
TEMPERATURE SENSOR
(33) COMBUSTION
(33) COMBUSTION
(33) COMBUSTION
(33) COMBUSTION
(13) INTERNAL PRIMARY
LOOP BALL VALVE
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
INTERNAL PRIMARY
(19) COMBUSTION
(19) COMBUSTION
(35) HEAT EXCHANGER
SURFACE TEMPERATURE
SWITCH
3 - COMPONENT LISTING
(36) ASME
PLATE
(21) SUPPLY WATER
TEMPERATURE SENSOR
& HIGH LIMIT SWITCH

10
FIGURE 4-1 Clearance to Combustible Materials
TABLE 2: BOILER CLEARANCES
Dimension Combustible
Materials (1) Service(1)(2)
Model 050/075/100/
150/200 050/075/100/ 150/200
Top (A) 0" (0 cm) 14" (36 cm)
Left Side (B) 0" (0 cm) 0" (0 cm)
Right Side (C) 0" (0 cm) 0" (0 cm)
Front (D) 0" (0 cm) 6" (16 cm)
Back (E) 0" (0 cm) 0" (0 cm)
Bottom (F) 0" (0 cm) 12" (32 cm)
Combustion Air/Vent
piping
0" (0 cm) 6" (16 cm)
Hot Water Piping See local code 6" (16 cm)
(1) Required distances measured from boiler jacket.
(2) Service, proper operation clearance recommendation.
A
E
ED
A
C
B
A
FLOOR
FLOOR
A
D
FF
F
F
4.1 Boiler Location Considerations
• Ambient room temperature always above 32°F (0°C) to
prevent freezing of liquid condensate.
• Approved for installation in closets.
• Protect gas ignition system components from water
(dripping, spraying, rain, etc.) during operation and
service (circulator replacement, condensate trap, control
replacement, etc.).
• Wall mount only.
• Access to outdoors to meet minimum and maximum
pipe lengths for combustion air and vent piping. See
section 6.
• Disposal of condensate. See section 6.
• Drainage of water (or water - antifreeze solution) during
boiler service or from safety relief valve discharge. See
section 5.
• Access to system water piping, gas supply, and electrical
service. See sections 5, 7 and 8.
• Clearances to combustible materials and service
clearances. See Table 2 and gure 4-1.
• Multiple Boilers can be wall mounted, placed side by
side, or back to back.
4 - LOCATING BOILER