CleaverBrooks profire q, Installation, Operation And Maintanance

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Adjustments
4-2 750-370
ProFire Q Series Manual
4.2.2 — Gas Adjustments
Low fire combustion analysis typically is 7% to 9% O
2
and less than .04% CO (400 ppm). A high fire reading typically
is 3% to 4% O
2
and less than .04% CO.
4.2.3 — Honeywell V48A Gas Valve Adjustment
1.
The bleed valve screw should be open one (1) turn counterclockwise from the fully closed position as a starting
point.
2.
Adjust the bleed valve in 1/4 turn counterclockwise increments until the V48A gas valve opens at the desired open-
ing speed for a smooth main flame ignition.
3.
The burner should be cycled between adjustments.
4.3 — Electrical Interference Test
Prior to putting the burner into service, conduct the following test to ascertain that main power will not cause the flame
relay to pull in.
Gas Fired Test:
1.
Close the manual gas valves.
2.
Start the burner, the flame relay should not pull in (be energized).
3.
Upon completion of successful test, proceed with startup procedures.
4.
Reconnect the power supply and proceed with startup procedures.
4.4 — Gas System
4.4.1 — Gas Pressure
Gas must be supplied at a pressure high enough to overcome the pressure loss in the burner gas train and furnace
pressure while running at full input. Refer to nameplate inside control panel for gas pressure requirements at train inlet
and manifold. The pressures listed are based on nominal 1000 Btu/cu ft. natural gas at elevations up to 2000 feet above
sea level.
4.4.2 — Gas Flow
The volume of gas is measured in cubic feet as determined by a meter reading. The gas flow rate required depends on
the heating value (Btu/cu ft.). The supplying utility can provide this information as well as pressure correction factors.
To determine the required number of cubic feet per hour of gas, divide burner input (Btu/hr) by the heating value (Btu/
cu ft.).
NOTE: The gas train components ship loose, therefore, the bleed valve will need to be installed and adjusted in the field.
NOTE: When checking the input rate, Make sure no other equipment is operating on the same meter.