Reviewed by the GTA Pool Contractors editorial teamLast reviewed How we research
Heater quotes look inconsistent because “heater repair” covers three different jobs: a diagnostic visit, a component repair, and a replacement. A $400 repair and a $4,000 replacement are not competing prices, and a quote that does not say which one it is cannot be compared.
The symptom tells a technician what to bring, which is often the difference between one visit and two. It also stops you approving a replacement for a $300 part.
| Symptom | Likely cause | What to check |
|---|---|---|
| No heat, no display | Breaker, fuse or control board | Check the breaker and any external timer first. If the board is dark with power present, it needs a technician. |
| Clicks, no ignition | Igniter, flame sensor or gas supply | Confirm the gas valve is open and other gas appliances work. A repeated click-then-lockout is the classic igniter pattern. |
| Fires then shuts off | Pressure switch, low flow or a blocked vent | Check filter pressure and the pump basket. A dirty filter is the most common cause of a heater short-cycling. |
| Runs but water stays cold | Scaled or failed heat exchanger, or low gas pressure | If the unit fires and the outlet pipe stays cool, the exchanger is not transferring heat. Get a quote before approving parts. |
| Loud banging or gurgling | Scale, trapped air or a failing blower | Scale is a water-chemistry problem that quietly shortens the exchanger's life. Fix the chemistry with the repair. |
A gas heater transfers heat through a metal exchanger sitting in the water. When the chemistry drifts, that metal scales, corrodes and eventually perforates. Once it is gone the unit is scrap: a new exchanger usually costs close enough to a new heater that replacement is the honest recommendation.
That is why a heater failure is worth reading as a water-chemistry signal. If the exchanger has scaled through, the same water has been working on the rest of the equipment too. Fix the balance with the repair rather than after the next failure.
A heat pump has no flame and no gas line. It moves heat from the air into the water, so the faults are electrical and refrigerant-side: a fan motor, a capacitor, a defrost sensor, a board, or low charge. It also loses output as the air cools, which is why a unit that worked in September can feel useless in a cold May.
Do not let anyone recharge a heat pump without finding the leak first. Topping up a system that is losing refrigerant buys a season at most.
Related: the full GTA repair price list and the heater troubleshooting walkthrough.
Heater repair price bands
| Service | Typical low | Typical high |
|---|---|---|
| Diagnostic service callOften credited against the repair if you approve it the same visit — ask before booking. | $95 | $185 |
| Heater repair (ignition, sensor, manifold)Common faults are a flame sensor, pressure switch or a cracked manifold. Parts included. | $350 | $900 |
| Heater replacementGas and heat-pump units are priced differently; load sizing and gas line work move the number. | $2,400 | $5,500 |
Planning ranges in CAD, before HST. Parts included unless the note says otherwise. Not quotes.
If you smell gas, stop. Shut the valve if you can reach it safely, leave the area and call your gas utility. That is not a pool contractor call.
Local crews
Public records are site checked; insurance and WSIB are not on file — verify both before you book.
Public Google Maps record
Public Google Maps record for a pool contractor listed in Brampton. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Brampton
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Toronto. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Toronto
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Burlington. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Burlington
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Oshawa. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Oshawa
Pricing
On request
Serves Oakville
Oakville service shop and equipment supplier on Redwood Square: water care, pumps, filters, heaters and salt systems.
Oakville
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Whitby. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Whitby
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Milton. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Milton
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Brampton. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Brampton
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Caledon. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Caledon
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Mississauga. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Mississauga
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Pickering. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Pickering
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Ajax. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Ajax
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Oakville. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Oakville
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Ajax. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Ajax
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Mississauga. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Mississauga
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Toronto. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Toronto
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Caledon. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Caledon
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Whitby. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Whitby
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Ajax. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Ajax
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Milton. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Milton
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Caledon. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Caledon
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Caledon. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Caledon
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Brampton. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Brampton
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Vaughan. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Vaughan
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Vaughan. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Vaughan
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Toronto. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Toronto
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Toronto. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Toronto
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Mississauga. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Mississauga
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Whitby. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Whitby
Pricing
On request
Serves Mississauga
Leak detection and underwater repair with certified divers. Same-visit detection and repair since 2007; does not take general service work.
Mississauga
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Richmond Hill. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Richmond Hill
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Brampton. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Brampton
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Oakville. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Oakville
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Whitby. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Whitby
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Whitby. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Whitby
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Ajax. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Ajax
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Markham. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Markham
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Caledon. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Caledon
Pricing
On request
Serves 5 GTA cities
East-end Toronto and York Region crew running openings, closings, vinyl liner leak detection and pre-sale pool inspections since 2008.
Toronto · Markham · Richmond Hill · Ajax + more
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Toronto. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Toronto
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Oshawa. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Oshawa
Pricing
On request
Public Google Maps record
Public Google Maps record for a pool contractor listed in Oshawa. Contact details come from the company's published listing; insurance, WSIB and TSSA are not on file.
Listed in Oshawa
Pricing
On request
Heater FAQ
A diagnostic visit is $95–$185 and is usually credited against the work if you approve it that day. The repair itself runs $350–$900 depending on whether it is ignition, a sensor, the manifold or the blower. A full replacement is $2,400–$5,500 installed, before HST, and gas line work or venting changes are extra.
In order of likelihood: a failed igniter or flame sensor, a pressure switch that will not close because the pump is not moving enough water, low gas pressure, or a blocked vent. Those are all serviceable parts. A cracked or corroded heat exchanger is the one that usually ends the unit.
Repair if the unit is under about eight seasons old and the fault is ignition, a sensor, a blower or a board. Replace when the heat exchanger is cracked or scaled through, when the cabinet has rusted out, or when the quote passes roughly half the price of new equipment. Heat exchangers fail early when pH and alkalinity are allowed to drift.
A heat pump pulls heat out of the air, so the coil runs colder than ambient and can frost in cool, damp weather. Light frosting that clears on its own during a defrost cycle is normal. A solid block of ice, or icing that never clears, points to a defrost sensor, a fan fault or low refrigerant — all technician work.
It depends on the season and your rates, not on the brochure. A heat pump is most efficient in warm air and loses capacity as the air cools, so it extends the season well in September and struggles in a cold May. Gas heats faster regardless of air temperature. Ask for the rated output at the temperature you actually swim in, not the peak number.
Yes — a covered pool loses far less heat, so the heater cycles less for the same temperature. What you should not do is run it with the pump off or with low flow: most units have a pressure or flow switch precisely because dry-running destroys the exchanger.
Describe the symptom once. We reply with available local options, including a diagnostic fee and a range — free, no obligation.