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DIY guideAC and heat pump

Check the AC is actually cooling

Run it, check the filter and the airflow at each register, and compare the air going in and coming out with a thermometer.

  • 20 to 40 min
  • 8 steps
  • Every step animated
Check the AC is actually cooling: the animation’s first picture

8 steps

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  1. Set the thermostat well below the room and let the AC run for 15 minutes.

  2. Look at the furnace filter. A clogged one cuts the airflow and the cooling: change it.

  3. Hold your hand at each register. Air should come out steadily in every room.

  4. Hold a thermometer at the return grille for a minute and note the reading.

  5. Do the same at the register nearest the furnace.

  6. The supply should be about 15 to 20 °F (8 to 11 °C) cooler than the return.

  7. The outdoor unit's fan should spin and blow warm air out of its top.

  8. Little difference, ice on the pipes, or the outdoor fan still: turn the AC off and ask Handyman for a heating and cooling tech.

What you need

  • A kitchen or probe thermometer
  • A new furnace filter, if it's dirty

Call a pro if

  • The air coming out is barely cooler than the air going in
  • There's ice on the pipes or the indoor coil
  • The outdoor fan doesn't spin
  • It runs all day and the house stays warm

Handyman says: Not cooling? I'll find an HVAC tech.

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