11
OPERATING INSTRUCTIONS (HEATING)
NOTE: Figure 2 illustrates the proper gas valve mounting
location.
OFF
ON
Figure 11
Honeywell Gas Valve SV9500
(Top View)
IG
NIT
O
R
CO
NT
RO
L
OF
F
ON
½
PSI
IN
Figure 12
Honeywell Gas Valve SV9501
(Top View)
1. Close the manual gas valve external to the unit.
2. Turn off the electrical power supply to the unit.
3. Set the room thermostat to its lowest possible setting.
4. Remove the heat exchanger door on the side of the unit
by removing screws.
5. This unit is equipped with an ignition device which
automatically lights the pilot. Do NOT try to light burner
by any other method.
6. Turn the gas control valve knob or switch to the OFF
position. Do not force. (Figures 11 or 12)
7. Wait five minutes to clear out any gas.
8. Smell for gas, including near the ground. This is impor-
tant because some types of gas are heavier than air. If
you have waited five minutes and you do smell gas,
immediately follow the instructions on the Page 2 of this
manual. If having waited for five minutes and no gas
smell is noted, turn the gas control valve knob or switch
to the ON position. (Figures 11 or 12)
9. Replace the heat exchanger door on the side of the unit.
10. Open the manual gas valve external to the unit.
11. Turn on the electrical power supply to the unit.
12. Set the thermostat to desired setting.
GAS INPUT AND PRESSURES
Gas supply pressure and manifold pressure with the burn-
ers operating must be as specified on the rating plate.
GAS PRESSURE CHECKS
Gas inlet pressure must be checked and adjusted in accor-
dance to the type of fuel being consumed.
WITH POWER AND GAS OFF:
1. Connect a water manometer or adequate gauge to the
inlet pressure tap of the gas valve.
Inlet gas pressure can also be measured by removing the
cap from the dripleg and installing a predrilled cap with a
hose fitting(Figure 14).
WITH POWER AND GAS ON:
2. Put unit into heating cycle and turn on all other gas
consuming appliances.
Inlet Gas Pressure
Natural
Min. 5.0" W.C., Max. 10.0" W.C.
Propane
Min. 11.0" W.C., Max. 13.0" W.C.
Figure 13
Inlet Gas Pressure
Note: Inlet Gas Pressure Must Not Exceed the Maximum
Value Shown.
If operating pressures differ from above, make necessary
pressure regulator adjustments, check piping size, etc.,
and/or consult with local utility.
Figure 14
Measuring Inlet Gas Pressure
Alternate Method
CHECK THE MANIFOLD PRESSURE
A tapped opening is provided in the gas valve to facilitate
measurement of the manifold pressure. A “U” Tube manom-
eter having a scale range from 0 to 12 inches of water should
be used for this measurement. The manifold pressure must
be measured with the burners operating.