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TROUBLE SHOOTING GUIDES CONTINUED
General Gas Furnace
See gas furnace Instruction Manual Included with gas furnace(s) for trouble shooting details.
TROUBLE SHOOTING GUIDES CONTINUED
Electronic-Regulator
SYMPTOM
POSSIBLE CAUSE
FIELD TEST
REMEDY
1. Faulty automatic control valve.
1. Remove wire from valve, if valve doesn’t close —valve is faulty.
1. Replace automatic control valve.
2. Installation wiring error.
2. Remove wire from amplifier terminal 10 and 11. If valve remains open
check for miswiring.
2. Correct wiring.
3. Amplifier is faulty.
3. If AC voltage will not drop to zero at terminals 8 and 11 when DC voltage at
terminals 1 and 2 is above 20 V DC, amplifier is faulty.
3. Replace amplifier.
1. Faulty automatic control valve.
1. Read voltage across valve terminals. If 24 V AC, valve is faulty.
1. Replace automatic control valve.
2. Open wire to automatic valve.
2. Read voltage across terminals 8 and 11 on amplifier. If 24V AC, check for
open circuit to automatic valve. If space temperature is less than 60° or
greater than 85°F.
2. Correct wiring.
3. Amplifier is faulty.
3. If AC voltage reading remains zero when DC voltage at terminals 1 and 2 is
below 14V DC, amplifier is faulty. If space temperature is less than 60° or
greater than 85°F.
3. Replace amplifier.
1. Faulty power supply.
1. Read voltage at amplifier terminals 8 and 14 (24 V AC).
1. Power supply must be 24V AC.
2. MR valve installed backward.
2. Arrow on MR valve should point in direction of gas flow.
2. Install properly.
1. Room Override Thermostat, if used,
calls for heat.
1. Remove T115 wires from amplifier terminals 3 and 14.
1. If proper operation is obtained, check thermostat
wiring for shorts. Rotate thermostat dial above and
below room temperature to prove thermostat
function.
2. Open circuit in sensing and setting
circuit.
2. Disconnect and measure across wires connected to amplifier between
terminals 3 and 4 (A1010). Should read between 8,000 and 12,000 ohms.
2. If above 12,000 ohms check circuit for open or
loose wires.
1. Open circuit in wiring to MR valve.
1. Check wiring for defects.
1. Replace wiring if necessary.
2. Plunger jammed or installed upside
down.
2. Plunger should be smooth and clean and operate freely in solenoid sleeve. 2. Clean or replace plunger.
3. Faulty MR valve.
3. Measure voltage across MR valve.
F. Furnace won’t activate due
to constant high modulating
voltage (above 17 VDC).
1. Short circuit in sensing and setting
circuit
1. Disconnect and measure across wires connected to amplifier terminals 3
and 4 (A1010). Should read between 8,000 and 12,000 ohms.
1. If below 8,000 ohms check circuit for shorts or
miswiring.
A. Automatic control valve will
not close despite full range of
modulating voltage at terminals
1 and 2.
B. Automatic control valve will
not open despite full range of
modulating voltage at terminals
1 and 2.
C. No gas flow.
E. Continuous high fire but
automatic valve cycles.
D. Continuous high fire.
Содержание B
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