Why is My Pool Heater Not Working?

Swimming pool heaters are the most complex piece of pool equipment on your pool equipment pad. Making repairs to pool heaters should be performed by competent personnel. Gas pool heaters using Natural Gas or LP (Liquid Propane) gas can be risky by combustion or exhaust of the pool heater.

Florida Pool Heating has created the Pool heater FAQ below to help property owners with pool heater repairs.

Heater Pilot Won’t Light?

This could be as a result of low gas pressure, inadequate air supply, or improper venting. Ensure that the gas is turned on, and for propane, make sure the tank has fuel. Also, check for water run-off from the roof or sprinklers that may be flooding the pool heater. Check to ensure the heater pilot tubing is intact and not clogged. Confirm that the pilot orifice is not clogged with rust or small insects. For millivolt heaters, if the pilot will not stay ignited, check the thermocouple’s output for 600 mv.

Heater Won’t Reach the Acceptable Temperature?

The thermostat may be set too low. If the heat loss is greater than the heater input – the heater may be too small, outside air temperature is too low, or your heater may have an insufficient gas supply. You may need to install a solar pool cover to slow heat loss from your pool. All pool heaters have high limit switches to avoid overheating. A faulty upper limit switch could shut off the heater, or the issue could be that the heater is genuinely overheating, perhaps from improper exhaust out of the top of the heater.

The Heater Cycles On and Off Before it Reaches the Desired Temperature?

Your pool heater may have inadequate water flow due to a dirty filter, closed valve, external bypass, reversed water connections, or pressure switch out of adjustment. It is also possible that your thermostat is out of calibration or requires to be replaced. For low speed or variable speed pool heaters, the heater will not work on low flow pump speeds.

I Hear “Clicking” or “Sparking,” But My Pool Heater Will Not Ignite

Enabling the pilot to light is half the battle. If it’s trying to light, but either won’t light the pilot or light the burner tray, there could be numerous reasons. Check your pool heater owner’s manual. Ensure that the heater gas valve is in the on position, and if LP (Propane) is being used, check the gauge on the tank.

How Can I Make My Pool Heater Last Longer?

Keep your heater clean and as dry as possible always. Sweep under the burner tray and clean any leaves off of the heat exchanger. Trim back foliage around and above the heater for wind and sun to lower moisture. Don’t cover around the heater, which traps moisture.

Keep rodents out through the use of mint sachets or mothballs during winter. Nesting rodents can remove insulation and chew on wires. Investing in a winter pool heater cover is also a decent idea to keep out the elements and rodents.

Pool heaters out in the weather typically last for about 15 years. At some point, an expensive pool heater repair like a new heat exchanger or another pilot/gas valve will have you weighing the advantages of a new pool heater. A skilled person should install replacement pool heaters; and it’s especially wise to hire a professional gas contractor to make the gas connection.

Resources and References:

• Making Your Pool Heater Last Long