What gas water heater installation involves
A gas heater connects to three systems: the water lines, the gas line and the vent. In Ontario gas work is legally limited to a registered contractor with licensed gas technicians, under TSSA rules. We check the gas pipe size and length to confirm it can deliver the input rating on the new heater's label. We confirm the vent type matches the heater. Then we fit a sediment trap and a manual shut-off on the gas drop, and leak-test with solution and a gauge.
| Venting style | How it exhausts |
|---|---|
| Natural draft | Up a lined chimney or B-vent by rising heat |
| Power vent | A fan pushes exhaust out a side wall in plastic pipe |
| Direct vent | Pulls in outdoor air for combustion and exhausts the same way |
Why North York houses need it
Many houses here were built with a gas furnace and a gas tank sharing one masonry chimney. Once the furnace becomes a high-efficiency unit venting out the side wall, the water heater ends up by itself in an oversized chimney that may not draft well. That is a common reason to switch to a power-vent tank. Henry Farm townhouses and older semi-detached homes often face this.
Plumber's tip: Install a carbon monoxide alarm on each storey of the home and outside each sleeping area. Ontario law requires them in homes with fuel-burning appliances.
How we write up the job
The order sheet records the heater model, input in BTU per hour, vent type and length, gas pressure test result, and the permit or notification filed. We also write down the draft test result for natural-draft units, because poor draft is a safety issue and not just a performance one. Details on permits are in our permits leaflet.
Signs you should call
- A pilot that goes out repeatedly.
- Soot near the burner or the vent hood.
- Your furnace was replaced and the heater now vents alone.
- A gas smell near the appliance; leave and call Enbridge's emergency line first.
If space is tight, a tankless unit may be the better fit.
Costs and what affects them
Venting changes, gas line upgrades and permits make the largest difference. We itemize each.
Job at a glance
| Category | Hot water |
|---|---|
| Tools | Pipe threader, manometer, combustion analyser, leak solution |
| Final test | Pressure test on new gas piping and a measured draft |
Tell-tale signs
- Switching from electric to gas hot water
- Moving the tank to a new location
- Venting needs to change for a new furnace
Steps on the job
- Check the gas line size and meter capacity
- Plan venting: chimney liner, B-vent or power vent
- Fit a drip leg and appliance shut-off on the new gas run
- Leak test, light, and measure combustion draft
Your questions on this one
Can I switch from electric to gas?
If there is gas in the house and a route for the line and vent, yes. It is a bigger job than a straight swap.
How long does installation take?
Replacing tank for tank normally wraps up in one visit. Venting changes can take longer.