Sections
Heating
Heat pumps, furnaces, boilers and dual-fuel systems: how they work and what they cost to run.
Guides
Guide
What size heat pump do I need?
Why floor area cannot tell you, what a Manual J load calculation measures, and how to match a heat pump to the result.
11 min read
Guide
Do heat pumps work in cold climates?
What "cold climate" means on a heat pump spec sheet, and how to tell whether a unit will keep your home warm on the coldest nights.
9 min read
Latest
Explainer
How do I set the switchover temperature on a dual-fuel system?
A heat pump with a gas furnace backup should switch at the colder of two temperatures: where it stops keeping up, and where it stops being the cheaper heat.
3 min read
Explainer
What does "aux heat" mean on a heat pump thermostat?
Aux heat is the backup that switches on when the heat pump alone cannot keep up. Why it appears, what it costs, and when it points to a problem.
3 min read