Part number 550-141-850/069976
GOLD GV Water boiler series 3 — manualGOLD GV Water boiler series 3 — manual
GOLD GV Water boiler series 3 — manualGOLD GV Water boiler series 3 — manual
GOLD GV Water boiler series 3 — manual
Troubleshooting — GCM lights (continued)XIg
CHART 3
—
LIMIT
&
POWER
lights flashing
Electrical shock hazard — Wherever you see
▲
TURN OFF POWER
▲
, follow the instructions. Failure to follow
instructions could result in severe personl injury, death or substantial property damage.
•
▲
TURN OFF POWER
▲
to boiler at 120 VAC service switch.
• Remove
CONTROL CIRCUIT
plug from control module receptacle (
Figure 34, Item 5
).
• Remove a wire from one of the limit control spade connectors.
• Connect an ohmmeter across the left and right pins on the center row of the limit circuit harness.
Does the ohmmeter indicate a shorted wire harness (zero ohms)?
NoYes
Is boiler hot?
• This is a lockout condition. The return water temperature
sensor has signaled a temperature higher than 240 ˚F, but
the boiler limit circuit is closed (indicating that the limit
control circuit did not catch the over-temperature condition).
This is probably an indication of a failure of the boiler limit
control and possibly the block temperature switch as well.
• Replace control wiring harness.
• Retest.
• Reconnect CONTROL CIRCUIT plug to control module.
• Remove WATER TEMP SENSOR plug from control
module receptacle (
Figure 34, Item 6
).
• Connector an ohmmeter across the plug pins to check
the sensor resistance.
Does the ohmmeter indicate a shorted sensor (zero ohms)?
NoYes
NoYes
• Replace water temp sensor.
• Retest.
• Close the external manual gas valve.
• Remove one wire from the limit control
space connector.
• Set a thermostat to call for heat. Then
turn on power to the boiler at the 120
VAC service switch.
• The boiler system circulator should come
on and the control module should try to
cycle the boiler.
• Allow the boiler circulator to run to cool
off boiler and system water.
• After the boiler and system water have
cooled, turn off power at the 120 VAC
service switch and open the external
manual gas valve.
• Set limit control knob to its minimum setting. Replace wire
to limit control spade connector.
• Set a thermostat to call for heat.
• Turn on power at 120 VAC service switch.
• Control module should cycle boiler on and begin heating.
• The limit control should shut off the gas valve when the
temperature at the boiler pressure/temperature gauge
has reached no more than about 20 ˚F higher than the
limit switch setting.
Does limit control shut off gas correctly?
NoYes
• Replace limit control
and block tempera-
ture switch.
• Retest.
• Replace control
module.
• Retest.