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HVAC Maintenance & Repairs

Keep a system running, and know when it is time to replace it

What a seasonal tune-up covers, the warning signs worth a service call, and how to weigh one more repair against a new system.

Before heating and cooling season

Seasonal tune-ups

  • Check refrigerant charge and the airflow across the coil
  • Clean the coils and clear the condensate drain
  • Test the safety controls, the igniter and the flame sensor
  • Tighten electrical connections and check the capacitor
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When something stops

Repairs

  • Write down what you hear, see and smell, and when it happens
  • Check the breaker, the filter and the thermostat batteries first
  • Ask for the diagnosis and the price in writing before work starts
  • Keep the old part if you want a second opinion
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Rows of air conditioning units and pipes in a plant room

Before you buy or sell

Inspections

  • An HVAC inspection goes further than a general home inspection
  • Ask for the age and model number of every unit
  • On fuel furnaces, ask about the heat exchanger and venting
  • Keep the report with the home’s other records
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An outdoor air conditioning unit fixed to an exterior wall

Weigh it up

Repair or replace

  • Look at the age of the system and how often it has failed
  • Weigh this repair against the ones likely to follow it
  • Systems that use R-22 face costly refrigerant, since production ended in 2020
  • Ask for both options, priced in writing, from the same visit
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A heat pump outdoor unit standing next to a brick wall

Checklist

Signs worth a service call

Cycling The system starts and stops every few minutes
Ice Frost or ice forms on the refrigerant lines or the coil
Water Water pools around the indoor unit or the furnace
Smell A burning or electrical smell: switch the system off and call
Alarm A carbon monoxide alarm sounds: get everyone outside and call 911

Keep reading

Related pages

AC units, furnaces, heat pumps, installs

Heating & Cooling Systems

Filtration, humidity, ventilation

Indoor Air Quality

Lower bills, efficient equipment, assessments

Energy Efficiency

Plan a smarter home climate

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