Heat Pump Maintenance

A gas furnace in North Texas works three or four months a year and sits idle the rest. A heat pump never rests that long. It runs through our long cooling season, gets a few quiet weeks in spring and fall, then heats through a winter of frosty mornings, defrost cycles, and the occasional ice storm. All of those hours land on the same compressor, outdoor fan motor, and coils, so caring for a heat pump is closer to maintaining two systems than one.

W3 Electric Heating & A/C maintains heat pumps for homeowners in Rowlett, Rockwall, McKinney, Garland, Wylie, Forney, and throughout the Dallas area. Our electrical license matters on these visits as much as our HVAC license, because many of the parts that wear out first are electrical: the capacitor, the contactor, the defrost controls, and the backup heat strips, which carry some of the largest loads in your home.

Heat pump maintenance is the routine care that keeps the system efficient in both heating and cooling: a professional visit before each season, and simple upkeep from you between visits. Its purpose is to catch slow problems, such as a weakening capacitor, a charge that has drifted low, or a defrost sensor that has stopped reading correctly, before they become a no heat call on the coldest night of the year.

It overlaps with two services you may already know. The fall visit is a heating tune up adapted to a heat pump, and that page details the pre-season heating checklist. The spring visit covers the same ground as AC maintenance. This page explains what is specific to heat pumps and how the two visits fit together. If your heat pump has already stopped working, you need heat pump repair instead.

The homeowner side of heat pump care takes a few minutes a month, and it heads off a surprising share of the service calls we see. None of it involves opening the equipment.

A heat pump pushes air across the indoor coil in both seasons, so a clogged filter hurts it all year. In summer, weak airflow can freeze the coil; in winter, it makes the heat pump run hotter and can cause it to shut itself off as a safety measure. Check the filter monthly and replace it when it looks dirty, which for homes with pets or allergies often means every month and for others every three. Use the correct size, with the airflow arrow pointing toward the equipment, and ask about air filtration if you want more than a standard filter offers.

The outdoor unit needs open air on every side to collect heat in winter and shed it in summer. Keep about two feet clear around it, with nothing on top, and pull back mulch, leaves, grass clippings, and shrubs before they reach the coil. Keep the gutters above it clear, because water dripping onto the unit during a freeze can build ice on the top and the fan that the defrost cycle is not designed to clear. If the pad has sunk or tilted, tell us, since a unit that is not level strains its refrigerant lines and may not drain defrost water properly.

Indoors, the condensate drain carries water away from the air handler all summer. Water in the pan under an attic air handler, or dripping from a pipe above a window, which is usually the backup drain line, means the main line is blocked and needs attention before it overflows into a ceiling. Outdoors in winter, light frost on the coil is normal and the defrost cycle clears it. Never chip or scrape ice off the unit, pile snow against it, or cover it while the system is in use. If it stays encased in ice after a storm, switch to emergency heat and call us.

Before the summer heat arrives, the technician cleans and inspects the outdoor coil, checks the refrigerant charge, tests the capacitor and contactor, measures motor current, clears the condensate drain, and confirms the right temperature drop across the indoor coil. On a heat pump we also confirm the reversing valve shifts cleanly into cooling, so the first hot week of the year is not its first real test. Our AC maintenance page covers the cooling side of this visit in more detail.

Before the first cold front, the technician runs the system in heating mode and checks the parts that only matter in winter. That means shifting the reversing valve into heating, forcing a defrost cycle to confirm the control board and coil sensor respond, measuring the current draw of each heat strip, checking the sequencers or relays that bring the strips on, and testing the limit switches that protect them. The high voltage connections at the air handler and the outdoor unit are checked and tightened as well. The rest of the pre-season checklist follows our heating tune up.

Some checks matter in every season. A charge that is slightly off costs efficiency in both modes, and a heat pump low on refrigerant ices quickly in winter, so the technician measures it at each visit rather than assuming it has not changed. Electrical connections loosen as they heat and cool through thousands of cycles. Coils, indoors and out, gather dirt that cuts heat transfer in either direction. Checking twice a year catches a developing problem within months, and each visit focuses on the side of the system that is about to work hardest.