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Pool Heater Repair in Underwood, Markham

On-time pool heater repair — get your pool warm again in Underwood, Markham.

Call (437) 475-2233
24 hour response
Licensed & insured
OEM parts on the truck

A pool heater that won't fire or won't hold temperature is the fastest way to shorten a swim season. Our team in Underwood, Markham services natural gas, propane, and heat-pump pool heaters — Hayward, Jandy, Pentair, Raypak, Rheem, Sta-Rite — and carries the ignition, sensor, and gas-valve parts that account for most repairs.

Why pool heater repair matters in Underwood, Markham

Season-Length Matters

Every day the heater is down is a day of the swim season you don't get back. Fast turnaround is the whole point of a specialist service in Underwood, Markham.

Efficient Heating

A well-maintained heater burns cleanly, hits temperature faster, and costs less to run — especially with today's gas prices.

Safe Combustion

Pool heaters live outside, often exposed to weather and debris. Regular repair-side attention keeps ignition, venting, and gas trains working the way they should.

Our pool heater repair process

  1. 1

    Full Diagnostic

    We test ignition, flame sensing, pressure switches, water flow, and control-board fault codes before naming a repair.

  2. 2

    Quote And Approval

    You get a written quote before we replace anything — parts, labour, and total up front.

  3. 3

    OEM Repair

    Factory-quality parts, sized to your specific heater. No universal substitutes on the gas train.

  4. 4

    Water Chemistry Note

    Where relevant, we point out chemistry issues (low pH, high salt) that are quietly destroying your heat exchanger.

  5. 5

    Startup And Verification

    We bring the heater up to temperature, verify the run, and hand you a report.

Common findings in Underwood, Markham

  • Failed ignition control modules
  • Corroded heat exchangers on older units
  • Sooted burners from restricted airflow
  • Low water flow triggering pressure-switch shutoffs

What you get

Back In The Water Fast

Most repairs in Underwood, Markham are completed on the first visit thanks to a stocked service vehicle.

Longer Heater Life

Small repairs done well beat replacing a $4,000 heater a season early.

Honest Assessment

If your heater is at end of life, we'll tell you and quote a proper replacement — no games.

Pool Heater Repair reviews in Underwood, Markham

4.9 average from 743 verified customer reviews
Bundled two services, saved the trip fee
Had the chimney and the dryer vent done on the same visit. Cheaper and half the disruption.
Farah N. - Markham - 2025-12-27
A real person answers the phone
No call centre, no chasing. Booked in two minutes and got a text when the truck was on the way.
Ryan K. - Mississauga - 2026-02-28
Documentation on everything
Photos, readings, and a written summary after every visit. Makes it easy to keep records for the house file.
Doug T. - Burlington - 2026-01-11
Reliable across three jobs
Used them for a sweep, a dryer vent, and a fireplace service. Same standard every time and the same technician twice, which I appreciated.
Helena B. - Toronto - 2026-04-17

FAQ

Do you service heat pumps?

Yes, alongside natural gas and propane heaters.

Is diagnosis free?

A flat trip and diagnostic fee applies and is credited toward the repair.

What brands do you service?

Hayward, Jandy, Pentair, Raypak, Rheem, Sta-Rite, Lochinvar, and Seresco among others.

Book your pool heater repair today

24 HOUR RESPONSE GUARANTEED — call now to lock in a slot in Underwood, Markham.

Call (437) 475-2233

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