At a glance
- 01
Buy or keep renting
A contractor can quote a purchase so you can compare it with your monthly rental fee.
- 02
Leaving a rental, properly
Returning a rented tank has a process. Contractors who do it often know the steps.
- 03
Venting checked
Power-vented and atmospheric tanks vent differently. Changing the furnace can affect the tank.
- 04
Same-day help for leaks
A leaking tank or no hot water can go in as urgent.
Hot water tanks in Ontario homes
Most houses around Hamilton heat water with a 40- or 50-gallon tank in the basement, usually natural gas, sometimes electric or propane in rural Haldimand and Norfolk. A tank typically lasts 8 to 12 years. It usually fails in one of two ways: it stops heating, which is often a repairable part, or it starts leaking from the tank itself, which means it is done. Hot water tank replacement is a common, quick job, usually a few hours.
Renting is the Ontario default
Ontario is unusual: a large share of water heaters are rented, often from a company that was once tied to the gas utility. The monthly fee covers repairs and replacement while you rent, but over the life of a tank it usually costs far more than buying one. If your tank is rented, the bill will show the company and the monthly charge. Our guide to renting or buying a furnace or water heater works through the numbers.
If you decide to buy, a contractor installs your own tank and the old rental unit goes back to the rental company. Rental agreements set out how a tank is returned and what fees apply, so read yours or ask the rental company first. Since 2018, Ontario has banned door-to-door selling of water heaters, furnaces and air conditioners. A knock at the door offering to "check your water heater" is not a utility visit.
Types of water heater
- Conventional gas tank: vents up a chimney, often sharing it with an older furnace. The cheapest gas option.
- Power-vented gas tank: a fan pushes exhaust out through a plastic pipe in the wall. Needed when the chimney is gone or too big after a furnace upgrade.
- Electric tank: simple and no venting, but more expensive to run in Ontario than gas.
- Tankless (on-demand): heats water only as you use it. See tankless water heaters.
- Heat pump water heater: an electric tank with a small heat pump on top, much cheaper to run than plain electric. It cools and dries the basement around it.
Repair or replace?
No hot water on a gas tank is often a pilot that will not stay lit, a failed thermocouple or a faulty gas control valve. On a power-vented tank it can be the fan or a pressure switch, and on an electric tank a heating element or thermostat. Those are repairable. Water pooling under the tank, rust-coloured water from the hot taps or a tank more than 12 years old usually point to replacement. If the tank is rented, call the rental company first; repairs are their responsibility.
Safety: temperature and the relief valve
Tanks should store water at about 60 °C to prevent Legionella bacteria, but water that hot scalds quickly. A mixing valve keeps water at the taps below about 49 °C, and newer installations often include one. Every tank has a temperature and pressure relief valve with a pipe running down toward the floor. If it drips or discharges, the tank is overheating or over-pressured and needs a technician. Never cap or plug it.
Furnace changes can affect the tank
When an old mid-efficiency furnace is replaced with a high-efficiency one, the furnace stops using the chimney. A gas water heater left alone in a large chimney may not draft properly, which can spill exhaust into the basement. The fix is a chimney liner or a power-vented tank. A good contractor checks this when replacing either appliance, and every home with gas appliances should have working carbon monoxide alarms.
Who can install one
Gas and propane water heaters must be installed by a TSSA-certified gas technician working for a registered contractor. Electric tanks need correct wiring under ESA rules. The contractor should also fit a drain pan where a leak could damage finished space, and an expansion tank where the plumbing needs one.
How the request works
You request water heater service once, and we pass it to one licensed contractor who works your area. Say whether the tank is gas, electric or propane, whether it is rented or owned, roughly how old it is, and whether it is leaking. If you have a large household or want endless hot water, ask for a tankless quote too, and read tankless vs tank.
Typical prices
CAD · before GST/HST
- Gas tank, 40–50 US gal, conventional ventInstalled
- $2,000–$3,000
- Gas tank, power-vented
- $2,500–$3,500
- Electric tank, 40–60 US gal
- $1,500–$2,500
- Common repair (thermocouple, igniter, valve, element)
- $200–$600
- Rental, for comparisonBefore tax, depending on the tank and company
- $25–$45 a month
Typical 2026 installed prices in Hamilton and the surrounding area, before HST and before any rebate. They are a guide, not a quote: the contractor you are matched with sets the price after seeing the home.
Questions people ask
How much does it cost to replace a hot water tank in Hamilton?
A standard 40- to 50-gallon gas tank usually costs $2,000 to $3,000 installed, or $2,500 to $3,500 for a power-vented model, before HST. Electric tanks run $1,500 to $2,500.
Is it cheaper to rent or buy a water heater?
Over 10 to 12 years, buying almost always costs less than renting. Renting can make sense if you want no repair risk at all or are not staying in the house long.
How long does a water heater last?
Usually 8 to 12 years for a tank. Hard water, high temperature settings and skipping maintenance shorten it.
My water heater is leaking. What do I do?
Turn off the cold water supply valve on top of the tank, turn the gas control to off or switch off the breaker for an electric tank, and send an urgent request. If it is a rental, call the rental company.