Applied Air GAS-FIRED HEATERS, Инструкция по установке и эксплуатации

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Symptom Cause Remedy
E. If pilot does not light
after 90 second pre-
purge has timed out
and there is no voltage at
fl ame safeguard relay
output terminals.
I. Return air or outside air
damper not functioning
properly (see sequence
of operations).
J. Cooling not functioning
properly.
1. Flame safeguard relay
run/test switch in test
position or is defective.
2. Burner or draft motor not
running
3. Burner or draft air
proving switch is open.
1. Damper motor and/or end switch
not wired correctly or defective.
2. Thermostat, relays and/or poten-
tiometer not wired correctly or
defective.
3. Dampers binding and/or loose.
1. Thermostat and/or relays not wired
correctly or defective.
2. Setpoint is lower than design
conditions.
3. Insuffi cient cooling.
4. Condensing section or evaporative
cooler is not operating properly.
1. Place switch in run position, see
technical cut sheet on fl ame safe
guard relay, or replace if defective.
2. Check wiring, fuses, and amp
draw on motors.
3. Check for correct rotation of
motors and/or adjust switch.
1. Check wiring and/or replace
end switch.
2. Check wiring and/or replace
bad components.
3. Check and/or replace.
1. Check wiring and/or replace bad
components.
2. Adjust thermostat to correct
setpoint.
3. If desired space temperature
is not reached and cooling is
at full capacity, system may be
undersized.
4. See Trouble Shooting Guide
for your condensing section or
evaporative cooler.
SECTION VII - TROUBLESHOOTING
continued
G. If there is no heat with
pilot on and no
voltage is present at
fl ame safeguard relay
output terminals.
H. Flame safeguard
goes into alarm when
main fl ame is trying to
establish on units with
interrupted pilot.
1. Flame safeguard relay run/test
switch in test position or is
defective.
1. Pilot gas pressure may be too
high.
1. Place switch in run position,
see technical cut sheet on fl ame
safeguard relay, or replace if
defective.
1. Adjust needle valve – typically
1-1/2 to 2 turns open from closed
position.
F. If there is no heat with
pilot on and voltage
is present at fl ame
safeguard relay output
terminals.
1. Last manual gas shut-off valve
closed.
2. No gas on outlet side of
regulator with proper inlet
pressure.
3. No gas on outlet side of valve
or actuator with proper inlet
pressure.
4. Low fi re start switch, SW-10/SW-
12 in MT-11/MTR-4 is open (if
applicable).
5. Inlet gas pressure lower than
the required gas pressure.
6. Normally open vent valve (if
applicable) not closing.
7. Gas nozzles obstructed or
plugged.
1. Turn Heat "off-on" switch to the
"off"
position. Slowly open all
manual gas shut-off valves.
2. Clear obstruction in vent orifi ce
or line. Check for correct size
spring. Replace if defective.
3. Check wiring, voltage, and
adjustment. Correct wiring or
replace if defective.
4. Check for proper operation, see
sheet in manual for proper settings.
5. Increase gas pressure.
6. Check for correct installation
and voltage. Correct or replace.
7. Clear obstruction or blockage.
(see burner IOM)