How the job runs
- 1Calculate flowadd up the litres per minute of fixtures that may run at once
- 2Check gas supplymake sure the meter and gas piping are big enough for the bigger burner
- 3Plan ventingroute intake and exhaust through the wall with code clearances
- 4Mount and connectinstall the unit with service valves for flushing
- 5Commissionset the outlet temperature, open three taps together to load it, and show you the panel
01Sizing by flow
Tankless heaters are rated on how many litres a minute they can lift by a set number of degrees. In winter, the water coming from Lake Ontario through the city mains is cold, so the heater has to work harder. We size for a January morning, not a July one.
Two showers and a dishwasher at once needs a bigger unit than a single shower.
| Gas line | Often needs upsizing for the high burner input |
|---|---|
| Descaling | Hard water makes annual flushing important |
| Space saving | Frees up the floor space of a tank |
02Gas and venting
These units have powerful burners. The gas line from the meter may need to be larger. Venting goes out the side wall in plastic pipe, and the termination has to keep its code distances from openable windows, doors and the meter.
03Maintenance
Scale is the main enemy. Isolation valves let us flush the heat exchanger with a descaling solution. We recommend it every year in hard water areas.
04Condensate
High-efficiency units drain condensate to a floor drain.