Instructions / Assembly

4
RATE VERIFICATION
Refer to the lighting and Operating Instruction Plate located in control area of furnace for
instructions on lighting the pilot.
1. Make certain there is no gas flow through the meter other than to the appliance being
checked. Other appliances must remain off and the pilots extinguished (or their
consumption deducted from the meter reading).
2. With gas control knob in “ON” position, cycle main burner on and off several times by
means of thermostat o stabilize pressure regulator valve (PRV) diaphragm.
3. With second hand on watch, carefully clock gas meter to determine exact rate of gas
flow to main burner in cubic feet per hour (see CONVERSION TABLE below).
4. Compare actual input with manufacturer’s recommended hourly input stamped on rating
plate. Convert BTU per hour input rating to cubic feet of gas per hour (cfh) by using the
following formula.
Where as:
PRV = Pressure Input Rating in BTU per Hour = Cubic Feet of
Regulator Valve BTU Content of Gas per cu ft Gas per Hour
MJ= Megajoule Input Rating in MJ/hr = m3/hr
MJ of Gas per m3
M3= Metric Cube
5. If actual gas flow (cfh) does not conform to manufacturer’s recommended input rating
(cfh of BTU converted to CFH), a limited adjustment of the PRV may be made. Turn PRV
adjusting screw clockwise to increase or counter clockwise to decrease gas flow. Burner
input must not exceed nameplate rating.
6. Replace cap screw in PRV adjustment stack. Turn gas supply to other appliances back
on and re-light all pilots.
7. Place furnace in operation and observe through at least one complete cycle to be sure
all controls are operating satisfactorily.