8.Burner may not be firing at proper rate.

Check nozzle size.

Check fuel pump pressure setting.

COF-199 . . . . . . . . . . . 110 psig

All others . . . . . . . . . . . 100 psig

9.Burner may be short cycling. Short cycling (too frequent off and on) of burner will cause sooting. If unit or burner become dirty at frequent intervals, after correcting the dirt condition also correct the control settings (or other cause of the short cycling).

10.Oil burner fan wheel may be dirty.

Clean fan wheel with a stiff brush.

11.Draft regulator may be stuck.

Check to see if valve swings freely. Clean, if vane is stuck.

12.Priming control safety reset is open.

Reset safety switch on burner mounted primary control, see SAFETY PRIMARY CONTROL, page 22.

13.Burner motor safety reset is open.

BURNER STARTS-WON'T OPERATE

1.No oil in tank.

2.Oil line valve closed.

3.Loose connection in primary control.

Check and tighten all wire connections, see SAFETY PRIMARY CONTROL, page 22.

4.Electrode out of adjustment.

Clean firing head and readjust electrodes.

5.Clogged burner nozzle.

Replace with new nozzle, see nozzle chart, page 9, table 8.

Nozzle should be replaced semiannually.

6.Dirty filter.

Replace element in oil filter.

WATER IS TOO HOT

1. Refer to WATER TEMPERATURE, page 11.

WATER HEATER MAKES SOUNDS

1.Sediment or lime scale accumulations cause noises when the tank bottom should be cleaned. Refer to MAINTENANCE, page 12-13 for details.

2.Some of the electrical components of the water heater makes sounds which are normal.

Contacts click or snap as the heater starts and stops.

Transformers often hum.

WATER LEAKAGE IS SUSPECTED

1.Check to see if the water heater drain valve is tightly closed.

2.The apparent leakage may be condensation which forms on cool surfaces of the heater and piping.

3.If the outlet of the relief valve is leaking it may represent:

Excessive water pressure.

Excessive water temperature.

Faulty relief valve.

Excessive water pressure is the most common cause of relief valve leakage. It is often caused by a "closed system". If a check valve is in the inlet system it will not permit the expanded hot water volume to equalize pressure with the main. The relief valve must release this water or the water heater or plumbing system will be damaged. This condition is not covered by the limited warranty. The solution is to add a thermal expansion tank between the check valve and the water heater.

BURNER WON'T START

When the thermostat calls for heat but the burner won't start, check to make sure that you have proper voltage to the primary control.

CAUTION

When checking the low voltage circuit at the control, DO NOT TOUCH THERMOSTAT WIRES TO FLAME DETECTOR TERMINALSAS THIS WILL BURN OUT THE SENSOR IN THE SAFETY PRIMARY CONTROL.

If the voltage checks normal:

1.Flame detector may be sooted or seeing false light and will not let the motor replay pull in.

2.Loose wiring.

3.Bad flame detector (mounted inside housing beneath transformer).

4.Reset red safety button (primary control).

5.Defective primary control.

6.Reset motor protector.

BURNER STARTS BUT FAILS TO RUN

When the burner starts (motor running) but flame is not established, the control will lock out on safety in about 15 seconds. If the control does not lock out on safety, then the control is defective and should be replaced. When the motor is running but flame is not established, then the problem becomes:

1. There is insufficient or no oil getting into the combustion chamber.

2. There is no spark to ignite the oil.

If the problem is insufficient or no oil getting into the combustion chamber, check for the following:

1.Dirt or water in the supply line.

2.Slipping coupling between motor and pump.

3.Defective pump.

4.Clogged, defective or too small a nozzle.

5.Oil tank empty.

6.Clogged filter in oil line.

7.Restriction or kink in fuel line.

8.Ice in fuel line.

9.Air leak in inlet connections.

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A.O. Smith COF-199 Burner STARTS-WONT Operate, Water is TOO HOT, Water Heater Makes Sounds, Water Leakage is Suspected