Raypak pool heater troubleshooting

The company Raypak was founded in the 1947 in Southern California, USA. It is a leader in the production of copper finned boilers and heaters. Raypak supplies equipment worldwide. In particular, the company manufactures and supplies pool heaters. The troubleshooting table is represented below for cases of malfunction of Raypak pool heaters.

Harmonics, or whining noiseU.G. inoperative Check movement by putting in hot water (110°F or higher). If no movement, replace.
Debris or restriction in systemLocate 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 and check pool pH and total alkalinity.
Heater going on and off continuouslyDirty 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
Liming or scale forming on heat exchangerPool water Recommended pH should be between 7.4 and 7.8 Total alkalinity 100-150 PPM maximum.
Hardness 150-400 PPM maximum.
SuitingHigh flow rates Reduce by adding manual bypass valve. Adjust manual bypass valve until heater outlet water temperature is between 105° and 110°F.
U.G. Inoperative Check movement by putting in hot water (110°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.
Pilot outageLow gas pressure Adjust gas pressure. Clean pilot.
Restricted pilot Replace pilot.
Weak pilot generator
Yellow lazy flameLow gas pressure Adjust gas pressure. Clean burners.
Insects or debris clogging burner intake ports
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.
Takes long time to heat pool or spa.Calculate temperature in °/hr Heat rise (°/hr.)= Htr. output
Filter not running long enough Pool gallonage x 8.33 or refer to heater sizing chart. This does not take into account heat loss due to weather.
Dirty filter Reset time clock.
Gas line or meter undersized Clean filter.
Refer to installation instructions.
LimingBypassing 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 water chemistry properly.
Leaking at heat exchanger.Overacid Replace heat exchanger and maintain chemistry properly.
Gasket brittle and leaking - (overheated).Heater running after pump shuts off See pressure switch adjustment.
Refractory damage Replace refractory.
Sooted heater Determine cause of sooting and correct.
Combustion fan not runningFan relay Replace fan relay
Fan Loose connection or failed motor
Burned motor Incorrect wiring, replace blower