GAS PIPING LEAK CHECK
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result 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.
Burner ignition may not be satisfactory on first startup due to resid- ual air in the gas line or until gas manifold pressure is adjusted. The ignition control will make three attempts to light before locking out.
It is recommended that when the gas supply is first connected to the furnace, the ground union be loosened until the odor of gas is detected. When gas is detected, immediately tighten the union and check for gas leaks. Allow five minutes for any gas to dissipate before continuing with the
With furnace in operation, check all of the pipe joints, gas valve connec- tions and manual valve connections for leakage using an approved gas detector, a
The furnace and its equipment
The furnace must be isolated from the gas supply piping system by closing the equipment
IGNITION SYSTEM SEQUENCE
1.Turn the gas supply ON at external valve and main gas valve.
2.Set the thermostat above room temperature to call for heat.
3.System
a.The induced draft blower motor will start and come up to speed. Shortly after inducer
b.After this warm up, the ignition module will energize (open) the main gas valve.
c.After flame is established, the supply air blower will start in about 30 seconds.
With furnace in operation, check all of the pipe joints, gas valve connec- tions and manual valve connections for leakage using an approved gas detector, a
CALCULATING THE FURNACE INPUT (NATURAL GAS)
NOTICE
Burner orifices are sized to provide proper input rate using natural
gas with a heating value of 1030 BTU/Ft3 (38.4 MJ/m3). If the heat- ing value of your gas is significantly different, it may be necessary to replace the orifices.
NOTICE
If orifice hole appears damaged or it is suspected to have been redrilled, check orifice hole with a numbered drill bit of correct size. Never redrill an orifice. A
DO NOT bottom out gas valve regulator adjusting screw. This can result in unregulated manifold pressure and result in excess over- fire and heat exchanger failures.
NOTICE
DO NOT set manifold pressure less than 3.2 in wc or more than 3.8 in wc for natural gas at sea level. If manifold pressure is outside this range, change main burner orifices.
Verify natural gas input rate by clocking meter.
1.Turn off all other gas appliances and pilots.
2.Run furnace for a minimum of 3 minutes in heating operation.
3.Measure time (in sec) for gas meter to complete 1 revolution and note reading. The 2 cubic feet dial provides a more accurate mea- surement of gas flow.
4.Refer to Table 10 for cubic feet of gas per hour.
5.Multiply cubic feet per hour by heating valve (BTU/cu ft) to obtain input.
If clocked rate does not match the input rate from the unit nameplate. follow steps in next section to adjust the manifold pressure. Repeat steps 2 - 5 until correct input is achieved.
Burner ignition may not be satisfactory on first startup due to resi- dential air in the gas line or until gas manifold pressure is adjusted. The ignition control will make 3 attempts to light before locking out.
Be sure to relight any gas appliances that were turned off at the start of this input check.
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