How to Switch Your Heat Pump Between Seasons

You switch a heat pump between seasons with the thermostat, and the equipment does the rest. Set it to cool in summer and heat in winter, or leave it on auto and let it choose. What the seasonal change really calls for is a short round of checks so the system is ready before you lean on it.

Around Pasco and Richland that matters, because the shoulder seasons can swing forty degrees in a week and a heat pump that has sat idle for months tends to reveal its problems the first hot or cold day.

What the machine is actually doing

A heat pump moves heat instead of making it. In cooling mode it pulls heat out of your indoor air and releases it outside, exactly like an air conditioner. In heating mode a reversing valve flips the direction of the refrigerant flow, so the outdoor unit collects heat from the outside air and the indoor coil delivers it to your rooms.

Because it is one system doing two jobs, wear on the compressor, the coils and the valve builds year round. That is why a heat pump benefits from two service visits a year, one before each main season, rather than one.

What you can do yourself

Most of the homeowner work is simple and safe. Change or clean the filter. A one inch filter usually needs replacing every one to three months, and heat pumps run longer hours than a cooling-only system, so check yours more often than you think you need to.

• Clear leaves, cottonwood fluff, weeds and debris from around the outdoor unit, keeping a couple of feet of open space on every side
• Gently rinse dust off the outdoor coil with a garden hose on a soft setting, with the power off
• Make sure supply registers and return grilles are open and unblocked
• Run the system in the new mode for a few minutes at the thermostat and confirm the air feels right and the outdoor fan spins

What a technician should handle

The work that needs training and tools is the part that keeps the equipment safe and efficient. A technician can check the refrigerant charge, test capacitors and contactors, inspect electrical connections, verify the reversing valve shifts properly, clear the condensate drain, and look at the indoor coil and blower.

Refrigerant and electrical work is never a do-it-yourself job. If the system blows the wrong temperature after you change modes, do not keep cycling the thermostat. Call a licensed technician.

Watch the shoulder seasons

Spring and fall are when homeowners get confused, because a mild morning is followed by a chilly night. Resist the urge to flip the thermostat back and forth several times a day. Frequent mode changes make the system short cycle and add wear. Pick a mode for the week, or use auto with a few degrees of gap between the heating and cooling setpoints.

In winter, the outdoor unit will sometimes frost over and run a defrost cycle. A little steam and a brief pause in warm air is normal. A thick layer of ice that stays, or a unit that never seems to finish defrosting, is not normal.

A small habit helps here. Note the date of each seasonal check on the calendar, and glance at the outdoor unit whenever you mow or water. A stuck fan or a pile of debris is much easier to spot on a routine walk than on the first extreme day.

Signs it needs attention before the season starts

Rising energy use with no change in habits, unusual noises when the reversing valve shifts, weak airflow, or a system that struggles to reach the setpoint are all good reasons to schedule a visit early instead of waiting for the first extreme day.

Air-Tech installs and services heat pumps from its shop on N Oregon Ave in Pasco, including Trane and Mitsubishi Electric equipment, and the AT Advantage Program includes two visits a year so each season starts with a checkup. Questions about your own system are welcome at (509) 392-2021.