Tank vs Tankless Water Heaters

Tanks are cheaper up front and simple; tankless saves space and standby losses but costs more and needs maintenance.

A tank water heater keeps a reservoir of hot water ready. It is simple and less expensive to install, but it loses heat while sitting and can run out during heavy use. A tankless unit heats water only as it flows, saving standby energy and space, but it costs more and may need a larger gas line and new venting.

In winter, incoming water from Lake Ontario is cold, which reduces the flow a tankless unit can heat to shower temperature. Sizing for the coldest months is important. Scale from moderately hard water means tankless units need periodic descaling.

For households with modest demand, a tank remains a reliable, economical choice. For larger households or those short on space, tankless can be worthwhile.

1. Count bathrooms and peak simultaneous use
2. Check gas line size and venting options
3. Compare up-front and long-term costs
4. Consider water hardness and descaling

• Notepad for your hot water use

1. 01

   Note the most hot-water taps your household opens at the same moment

2. 02

   Check your gas line and meter size

3. 03

   Look at where venting can go

4. 04

   Compare upfront cost with long-term use

5. 05

   Consider water hardness and descaling

Tankless units heat water on demand but need enough gas flow to keep up when several taps run.

Whitby Plumbing, from the job

• You need a gas line upgrade
• Venting is complex
• You want a sizing check

Ring the desk for sizing help before your old tank fails.

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