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Heater will not fire or pool will not heat.

A licensed gas technician should handle gas work, and a licensed refrigeration technician should handle the heat pump circuit.

Customers put it like this

  • heater won't come on
  • heater keeps shutting off
  • it's making a knocking noise
  • black soot on the heater
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Stop first if

  • You smell gas at the heater or pad.Leave the area. Call the gas utility or emergency services from a safe distance.
  • The heater shows flame with no call for heat, or keeps firing with the pump off.Do not run it. Close the manual gas valve only if it can be done without risk. Call a licensed gas technician.
  • Any part of the heater has been under water.Do not operate it. Call a licensed gas technician.
  • There is scorching outside the burner area, vent corrosion or carbon monoxide in the space.Keep it off. Get people out and into fresh air. Call emergency services and a licensed gas technician.
01

Ask on the call

6

Homeowner? These are the questions a good technician will ask you. Having the answers ready makes the first visit count.

  1. Is the pump running, and at what speed?
  2. Is it a gas heater, heat pump, hybrid or solar?
  3. What does the display show?
  4. Does the trouble line up with the cleaner running or a pool and spa change?
  5. Was the filter cleaned or a valve moved lately?
  6. Have you seen soot, scorch marks or water under the heater?
02

Bring

5
  • Reference pool thermometer
  • Gas pressure manometer for a licensed tech
  • Multimeter
  • Filter pressure gauge
  • Flashlight
03

Check on site

6
  1. See that the pump runs at a speed the heater accepts, with clean baskets and filter.
  2. Make sure no valve is closed, and read the display for remote mode.
  3. Switch the pump off and on and watch whether the heater shuts off each time.
  4. After start-up, compare inlet and outlet pipes and listen for boiling or knocking.
  5. Compare the heater's reading with an accurate thermometer before blaming a sensor.
  6. A licensed gas technician reads gas pressures and inspects burners, venting and exchanger.
04

Keep on the record

5
  • Photo of the display and any fault code
  • Pump speed during the visit
  • Inlet and outlet pipe temperatures
  • Gas pressure readings from the technician
  • Photos of soot or scorching

General guidance for a qualified person, not a finding about any home. The person on site decides.