Discount Pool and Spa Supplies - Troubleshooting pool heaters and spa heaters

PROBLEM	CAUSE	SOLUTION

Heater cycling on and off continuously.	Dirty filter	Backwash filter.

	Low water level in pool	Raise water level.

	External bypass setting out of adjustment	Adjust bypass

	Pressure switch out of adjustment*	Adjust pressure switch

	Defective High Limit Switch	Replace High Limit Switch

Pilot outage - Millivolt systems only	Weak pilot generator	Replace pilot generator or assembly.
	Restricted pilot	Clean pilot.

	Low gas pressure	Adjust gas pressure.

Takes long time to heat pool or spa.	Calculate temperature in degrees/hr	Heat rise (degrees/hr.) = Heater output Refer to heater sizing chart or refer to heater sizing chart. This does not take into account heat loss due to weather.

	Dirty filter	Clean filter.

	Filter not running long enough	Reset time clock.

	Gas line or meter undersized	Refer to installation instructions.

Lazy yellow flame	Low gas pressure	Adjust gas pressure.

	Insects or debris clogging burner intake ports	Clean bumers.

Outer jacket very hot (paint blistered)	Broken refractory caused by shipping damage or improper combustion*	Replace refractory panels

	Excessive sooting of heat exchanger	Determine cause of sooting & correct.


Liming	Bypassing too much water	Inspect bypass for movement. If no movement, replace.

	U. G. not functioning	Replace if no movement when heated.

Leaking at well	Overacid	Replace well and maintain proper water chemistry

Leaking at heat exchanger	Overacid	Replace heat exchanger and maintain proper water chemistry

Gasket brittle and leaking (overheated)	Heater running after pump shuts off	Pressure switch needs adjustment or replacement.

	Retractory damage	Replace refractory.

	Sooted heater	Determine cause of sooting and correct.

Harmonics, or whining noise	U.G. inoperative	Check movement by putting in hot water (110-F or higher). If no movement, replace.

	Debris or restriction in system*	Locate the restriction and remove. Flush system and clean.

	Debris in gas line*	Remove debris or blow out gas line.
	Low flow	Scale forming in heat exchanger-clean heat exchanger. Check pool pH and total alkalinity.

Liming or scale forms on heat exchanger	Water out of balance	Recommended pH should be between 7.4 and 7.8 total alkalinity 100-150 PPM maximum. Hardness 150-400 PPM maximum.

Sooting	High flow rates	Reduce by adding manual bypass valve. Adjust by putting thermometer in header (1/4" NPT) drain opening. Set bypass so thermometer reads between 105-110 degrees Fahrenheit.
	U.G. Inoperative	Check movement by putting in hot water (110 degrees F or higher). If no movement, replace.

	Air starvation*	Refer to installation instructions.

	Improper venting*	Follow recommended installation instructions.

	Insects or debris clogging burner intake ports	Clean burners.

	*(Usually occurs on initial start-up)**

HEATER TROUBLE SHOOTING GUIDE