York Sun Premier GZA1M Series Start-Up & Operation page 18

5587001-YSG-A-520 | Start-Up & Operation Guide
WARNING
If the information in this manual is not followed ex-
actly, a fire or explosion can result and cause prop-
erty damage, personal injury, or loss of life.
Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
WHAT TO DO IF YOU SMELL GAS:
1. Do not try to light any appliance.
2. Do not touch any electrical switch, and do
not use any phone in your building.
3. Immediately call your gas supplier from a
neighbor's phone. Follow the gas supplier's
instructions.
4. If you cannot reach your gas supplier, call
the fire department.
Installation and service must be performed by a qual-
ified installer, service agency, or the gas supplier.
WARNING
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly could re-
sult in serious injury, death, or property damage.
Never test for gas leaks with an open flame.
Use a commercially available soap solution made
specifically for the detection of leaks to check all
connections. A fire or explosion may result causing
property damage, personal injury, or loss of life.
CAUTION
The gas heat exchangers may have a light oil film
on them from the manufacturing process. This oil
burns off on initial start-up and can produce smoke
and an unpleasant odor.
18
Pre-Start Checks
When starting up these units, it is imperative that ALL gas
fittings within the unit (in addition to the field installed gas
connections) are leak checked with a soap solution as
part of the unit commissioning process. The heat section
must be fired when checking the joints on the manifold
side of the gas valve. If any leaks are detected, the leaks
must be repaired immediately and all joints rechecked.
Verify wiring inside the burner compartment to ensure
the wiring/terminals are tight and securely connected
to the components, such as the ignition control, flame
sensor, gas valve, rollout switches, and igniter.
The gas heat start-up sequence begins with a 30-sec-
ond pre-purge. The next step in the sequence is clos-
ing the air proving switch. The heat section has a
combustion air proving switch. This switch must close
before the ignition sequence can initiate. If the air prov-
ing switch is closed after the 30-second pre-purge, the
ignition control energizes the spark igniter and opens
the gas valve.
The furnace ignition control uses flame rectification as
verification of burner operation. The minimum allow-
able flame current for operation is 0.7 DC microamps.
When the furnace ignition control does not prove a
flame in 7 seconds, it turns off the spark signal and
closes the gas valve. It waits 30 seconds and then initi-
ates a second ignition sequence.
When a flame is not proven during the second 7-sec-
ond trial for ignition, the control turns off the spark sig-
nal, closes the gas valve, waits 30 seconds, and then
initiates a third ignition sequence.
When flame rectification is not proven on the third try,
the ignition control locks out.
The heat section has two rollout switches mounted
above the burners. The purpose of the rollout switch is
to protect the gas heat section from flame rollout, or the
flame burning outside the heat exchanger. A restriction
in the heat exchanger or breach in the flue passages
can result in a rollout situation. The rollout switch is a
manual reset device.
The unit has two high temperature limit switches. One
is located at the heat exchanger vestibule panel, and
the other located in the area of the heat exchanger re-
turn bend. These limits are automatic reset devices.
When the limit opens, the ignition control de-energizes
the gas valve. On staged gas heat, as soon as the limit
closes, the ignition control re-initiates the ignition se-
quence. When the limit opens on a modulating gas heat
section, the ignition controller locks out the heat section.
YORK