How to Clean a Hayward Pool Heater Remove the screws from the pool heater top and take this piece off. Check the burner flames. Turn off the burners and allow them to cool. Disconnect the high-limit wires from the heat exchanger and the thermistor leads from the control panel. Remove the four screws from the retaining air deflector and take if off. Click to see full answer. In this manner, can a secondary heat exchanger be cleaned?The secondary heat exchanger or “reheat coil” is almost always located directly above the blower making them prone to collecting more dust and debris than air conditioning coils. This is why it is imperative to access, inspect and clean these coils in order to properly clean the system.Furthermore, how do you maintain a pool heater? General maintenance Regularly inspect the pool heater’s burner intake ports and remove any build up of debris. Check the burners for fraying or corrosion. Regularly clean your filter; heaters require a steady flow of water through the pool filter to operate properly. Moreover, how do you change the Armistor on a Hayward pool heater? To replace the thermistor: Turn pump, gas supply, and heater power “OFF”. Drain the heat exchanger of all water. Remove the front access panel. Remove the control box cover. Unplug the thermistor connector from the ignition control board. How often should you clean a heat exchanger?The association recommends reducing fuel costs by regularly cleaning heat exchangers to prevent fouling, which is often caused by a dirty, malfunctioning burner. Inspect heat exchangers at least once per year and clean them when they look dirty.