Sunlife Enterprises DM180, DM300, DM240 Manifold Gas Pressure Adjustment, Proper Flame Adjustment

356214-XIM-A-0108

MANIFOLD GAS PRESSURE ADJUSTMENT

Small adjustments to the high-fire gas flow may be made by turning the pressure regulator adjusting screw on the automatic gas valve.

Adjust as follows:

1.Remove the cap on the regulator. It's located next to the push-on electrical terminals.

2.To decrease the gas pressure, turn the adjusting screw counterclockwise.

3.To increase the gas pressure, turn the adjusting screw clockwise.

NOTE: The correct manifold pressure for these fur- naces is 3.65 IWG ±0.3.

BURNERASSEMBLYBRACKET

FLAMESENSORBULB

1/8"GAPBETWEENCARRY-OVER TUBEANDFLAMESENSORBULB

CARRY-OVERTUBE

FIGURE 22 - PROPER FLAME ADJUSTMENT

PILOT CHECKOUT

The pilot flame should envelope the end of the flame sensor. To adjust pilot flame, (1) remove pilot adjust- ment cover screw, (2) increase or decrease the clear- ance for air to the desired level, (3) be sure to replace cover screw after adjustment to prevent possible gas leakage.

Put the system into operation and observe through complete cycle to be sure all controls function properly.

BURNER INSTRUCTIONS

To check or change burners, pilot or orifices, CLOSE MAIN MANUAL SHUT-OFF VALVE AND SHUT OFF ALL ELECTRIC POWER TO THE UNIT.

1.Remove the screws holding either end of the mani- fold to the burner supports.

2.Open the union fitting in the gas supply line just upstream of the unit gas valve and downstream from the main manual shut-off valve.

3.Remove the gas piping closure panel.

4.Disconnect wiring to the gas valves and spark ignit- ors. Remove the manifold-burner gas valve assembly by lifting up and pulling back.

FIGURE 23 - TYPICAL FLAME APPEARANCE

Burners are now accessible for service.

Reverse the above procedure to replace the assem- blies. Make sure that burners are level and seat at the rear of the heat exchanger.

BURNER AIR SHUTTER ADJUSTMENT

Adjust burner shutters so no yellow flame is observed in the heat exchanger tubes.

CHECKING GAS INPUT

NATURAL GAS

1.Turn off all other gas appliances connected to the gas meter.

2.With the furnace turned on, measure the time needed for one revolution of the hand on the small- est dial on the meter. A typical gas meter usually has a 1/2 or a 1 cubic foot test dial.

3.Using the number of seconds for each revolution and the size of the test dial increment, find the cubic feet of gas consumed per hour from the Gas Rate - Cubic Feet Per Hour Table 23.

If the actual input is not within 5% of the furnace rating (with allowance being made for the permissible range

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