Air Pressure Switch - Weil-McLain GOLD CGt Manual

GOLD CGt Gas-Fired Water Boiler — Boiler Manual
11b
Troubleshooting — components

Air pressure switch

Check pressure switch setting
1. See Figure 33.
2. Remove both air pressure switch hoses from air
pressure switch.
3. Install tees and tubing as shown in Figure 33 to
inclined manometer.
4. Turn off gas valve and set thermostat to call for heat.
Inducer will run but burners will not ignite.
5. Check for 24 VAC between both air pressure switch
terminals.
6. If manometer reading is above the setpoint of the
switch, but there is not 24 VAC between both air
pressure switch terminals — replace air pressure
switch.
Pressure switch setpoint
1. The air pressure switch should drop out when the
pressure across switch is less than 1.53 inches w.c.
Troubleshooting air pressure reading
1. If manometer reading is lower than the setpoint
of the switch — check for possible causes:
• blockage in hoses
• obstruction in inducer housing outlet
• loose inducer wheel on motor shaft
• inducer motor not in proper rpm
• inducer back plate not sealed properly
• blockage in block assembly
• blockage in flue pipe or termination
• incorrect pressure switch
Ambient temperature switch
The ambient temperature switch wires into the boiler
limit circuit. If the temperature in the vicinity of the
switch exceeds 135°F, the switch will shut down the
boiler.
44
Make sure boiler water temperature is 100 °F or cooler before starting procedure to obtain
appropriate readings.
The boiler will not operate correctly unless pressure switch hoses are correctly located. The
red hose connects from the right side (positive) hose barb of the switch to the flue collector. The
white hose connects from the left side (negative) hose barb of the switch to the connector box
(between flue collector and inducer) as shown in
Return to normal operation
When pressure reading is correct and air pressure
switch is operating properly — remove tees and
reinstall hoses to air pressure switch.
Figure 33 Manometer connections
Suction
Inclined tube
manometer
White
White
d e
S i
l Red
n e
p a
i t e
W h
d I n t
R e
e r
i o r
.
Figure 33
If the switch shuts down the boiler, check the reason
for the high temperature in the space. Increase the size
of the ventilation air openings if necessary.
Part Number 550-110-290/0501
Pressure
Red
r
e
c t o
F l u
l l e
c o
R e
a r
p a
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l
p a
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l
071038