Allied A80US2VX - Heating System Service Checks; CSA Certification

508033-02Issue 2135Page 28 of 48
GAS VALVE
NEGATIVE AIR
PRESSURE PORT
POSITIVE AIR
PRESSURE PORT
MANIFOLD
PRESSURE TAP
INLET
OUTLET
SUPPLY
PRESSURE
TAP
GAS VALVE SHOWN IN THE ON POSITION
MANIFOLD PRESSURE ADJUSTMENT
(TURN CCW TO INCREASE PRESSURE)
Figure 16.
8. Move switch on gas valve to ON. Do not force. See
Figure 16.
9. Replace the access panel.
10. Turn on all electrical power to to the unit.
11. Set the thermostat to desired setting.
NOTE: When unit is initially started, steps 1 through 11
may need to be repeated to purge air from gas line.
Turning O Gas to Unit
1. Set thermostat to lowest setting.
2. Turn o󰀨 all electrical power to unit if service is to be
performed.
3. Remove access panel.
4. Move switch on valve to OFF. Do not force.
5. Replace access panel.
Failure to Operate
If the unit fails to operate, check the following:
1. Is the thermostat calling for heat?
2. Are access panels securely in place?
3. Is the main disconnect switch closed?
4. Is there a blown fuse or tripped circuit breaker?
5. Is the lter dirty or plugged? Dirty or plugged lters will
cause the limit control to shut the unit o󰀨.
6. Is gas turned on at the meter?
7. Is the manual main shut-o󰀨 valve open?
8. Is the internal manual shut-o󰀨 valve open?
9. Is the unit ignition system in lock out? If the unit locks
out again, call the service technician to inspect the unit
for blockages.
10. Is pressure switch closed? Obstructed ue will cause
unit to shut o󰀨 at pressure switch. Check ue and
outlet for blockages.
11. Are ame rollout switches tripped? If ame rollout
switches are tripped, call the service technician for
inspection.
Safety or Emergency Shutdown
Turn o󰀨 unit power. Close manual and main gas valves.
Extended Period Shutdown
Turn o󰀨 thermostat or set to “UNOCCUPIED” mode.
Close all gas valves (both internal and external to unit)
to guarantee no gas leak into combustion chamber. Turn
o󰀨 power to unit. All access panels and covers must be in
place and secured.
Heating System Service Checks
CSA Certication
All units are CSA design certied without modications.
Refer to the A80US2VX Installation Instruction.
Gas Piping
If a exible gas connector is required or allowed by
the authority that has jurisdiction, black iron pipe shall
be installed at the gas valve and extend outside the
furnace cabinet.
CAUTION
Do not over torque (800 in-lbs) or under torque (350
in-lbs) when attaching the gas piping to the gas valve.
WARNING
Gas supply piping should not allow more than 0.5”W.C.
drop in pressure between gas meter and unit. Supply gas
pipe must not be smaller than unit gas connection.
Compounds used on gas piping threaded joints should be
resistant to action of liqueed petroleum gases.
Testing Gas Piping
In case emergency shutdown is required, turn o󰀨 the
main shut-o󰀨 valve and disconnect the main power to
unit. These controls should be properly labeled by the
installer.
IMPORTANT