8
3 - COMPONENT LISTING
Illustrations are a depiction of the boiler for general location of parts and may vary depending on model.
2
1
17
10
15
12
11
20
22
5
21
25
23
24
14
7
ITEM
NO.
GMHB125
1
Pump with Air Separator
2
Boiler Drain Tap
3
System Return
4a
DHW Indirect Tank Return
4b
DHW Indirect Tank Supply
5
Gas Valve
6
DHW Indirect Tank Supply
7
Low Water Pressure Cutoff
8
System Supply
9
Condensate Trap
10
3-Way Valve with Motor
11
Water Safety Thermostat
12
NTC Heating sensor (Supply /
Return) QTY 2, (1 Shown for
clarity)
13
Ignition electrode
14
Spark Generator
15
Flue Sensor
16
Aerator
17
Coaxial Flue Connector
18
Heat Exchanger Temperature
Sensor
19
Heat Exchanger
20
Burner (not shown)
21
Flame Detection Electrode
22
Air/Gas Blend Manifold
23
Acoustic Silencer
24
Fan
25
Venturi
3
13
9
6
8
4a
18
4b
16
PN 240012363 REV. A [08/31/2018]
GMHB125 Heat Only