All installations and services must be performed by qualified service personnel.

The supply air temperature should be measured in the supply air trunkline approximately 12 inches downstream of the supply air outlet of the appliance.

NOTICE: Minimum temperature rise is 500 F.; maximum temperature rise is 800 F.

l.After final adjustments are completed, tighten all screws to fix the positions of the burner air band.

m.Check for the presence of oil leaks. Correct any oil leaks found.

n.Reassemble the burner compartment cover.

o.Start and stop the unit several times while checking for proper ignition of the burner. The flame should ignite and stabilize without any significant rumbles or pulsations.

3.Adjustment Of Heat Input Rate

This appliance was shipped from the factory with one, fixed, main burner nozzle sized to produce the low-fire input rate using no. 2 fuel oil at the pump pressure shown on the rating label. The input rate can be changed to the high-fire by switching to the larger burner nozzle and increasing the pump pressure.

The main burner oil nozzles for this unit were selected based upon the following assumed characteristic values of the fuel oil suitable for use with this appliance design:

For no. 2 distillate fuel (domestic heating) oil having a higher heating value of 140,000 BTU per gallon and a specific gravity of 0.88 @ 60 deg. F. (or “gravity” of 30 deg. API @ 60 deg. F.).

It is possible to make minor adjustments to the heat input rate by adjusting the pump pressure. Sizeable changes in input rate (especially reductions) should be made by replacing the burner nozzle. To adjust the pump pressure to the main burner:

a.With the oil shut off, remove the 1/8 in. NPT threaded pipe plug located on the lower rear side of the oil pump, refer to Figure 13. Attach a pressure gage, capable of measuring pressure in pounds per square inch gage, PSIG, in this opening, on the discharge side, of the oil pump.

NOTICE: It may be necessary to remove the oil pump to attach the plumbing required to connect a pressure gage to the pump.

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Thermo Products 36)- 80, OPB (24, 30 service manual Adjustment Of Heat Input Rate