DIY guideThermostat
Switch the thermostat over for the season and test a full cycle
Change the thermostat from heat to cool, or back, and watch one full cycle run, so a problem shows now rather than on the first cold night or hot day.
- 20 to 40 min
- 7 steps
- Every step animated
7 steps
Tap a step to watch it again.
Set the thermostat's mode to Heat for the cold months, or to Cool for the warm ones.
If the AC's outdoor switch was off for the winter, turn it back on a day before you test cooling.
Set the temperature a few degrees above the room for heat, or below it for cool, so it has to start.
Give it a few minutes: many systems wait a little before they start. You should hear it come on.
Hold your hand at a vent or a radiator: warm for heat, cool for cool, with a steady flow.
Let it run until the room reaches the setting and it stops by itself. Then set the temperature you want.
If it never starts, blows the wrong temperature or keeps stopping and starting, check the filter and the furnace switch, then ask Handyman for a heating and cooling tech.
What you need
- A few minutes near a vent or a radiator
- Fresh batteries, if the thermostat's screen is faint
Call a pro if
- It never starts, or blows the wrong temperature
- It keeps stopping and starting
- The outdoor unit hums but its fan doesn't turn
Handyman says: Not working? I'll find an HVAC tech.
Free for every home. Handyman asks a few questions, then books a pro it trusts.
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