Heating a pool through a Toronto shoulder season

In July a Toronto pool barely needs a heater. The decision between gas and a heat pump is really a decision about the shoulder seasons, and it turns on one physical fact: a heat pump moves heat from the outside air, so it loses capacity as that air cools. It is far cheaper per month while the weather is mild and progressively less able to do the job as the season closes.

That is why the same equipment reads differently in Toronto than in a milder climate. An April or October swim here leans on a gas heater in a way it simply would not further south. If you only ever intend to swim between June and early September, the heat pump's running cost is the argument that matters. If the point of the heater is to stretch the season at both ends, capacity in cool air is.

Apex Electric Mechanical, working in Toronto and the GTA, puts a natural gas pool heater at $3,500 to $9,500 total installed and an electric heat pump at $5,000 to $11,000 total installed. Swimpool 360, quoting Ontario-wide, puts a gas heater installed at $2,500 to $5,500, and PF Pools puts gas purchase and installation at $3,000 to $5,500.

The gas figures cluster tightly enough to be useful. The spread inside them is mostly the gas line: a heater sited near an existing meter is a different job from one at the far corner of a lot, and Apex prices the equipment alone at $2,000 to $5,500, which shows how much of the total is labour and connection rather than the box itself.

Ontario adds a layer that a heater price list rarely mentions. Apex Electric Mechanical lists a TSSA inspection at $50 to $200 and an ESA inspection at $100 to $300, and Swimpool 360 prices the building or gas permit at $150 to $500 on top.

None of those is large on its own. Together they are several hundred dollars that a homeowner comparing two heater quotes may find in one of them and not the other, which makes the cheaper quote look cheaper than it is. Ask directly whether inspection and permit fees are inside the number.

John C Young Design puts a whole Ontario season of heating at $400 to $1,200 a year, and Mayascapes Pools puts pool heating at about $1,000 a season in Ontario. On most Ontario pools that is the largest single line in the running costs, larger than service and larger than chemicals.

Which is why the cheapest upgrade is worth doing first. Swimpool 360 prices a thermal or solar cover at $150 to $800 and recommends it as an add-on to any heater, because most of what a heater buys is lost overnight through the surface. A cover does not replace a heating decision, it makes whichever one you make cost less.

First: where is the gas line or the electrical service, and what does it cost to reach the heater from there? That single answer explains most of the range between $3,500 and $9,500.

Second: what months is this sized for? A heat pump specified for July and asked to work in April is not underperforming, it is being used outside what it was chosen for. Getting that written down before the install is what stops the argument afterwards.

Ontario HST is 13 percent and none of the GTA heater sources checked here quote with it included, so add it before you compare against a budget.