Heat Pump Struggling in the Cold: What Is Normal, and How to Hire an HVAC Technician

How Your Heat Pump Works in Cold Weather

Heat pumps heat your home differently than older furnace systems. Furnaces often provide short bursts of very hot air. Heat pumps deliver slow, steady heat instead. They ramp up to work harder on colder days and slow down on milder ones. This steady operation is most efficient. Try to keep your thermostat at a steady temperature. Lowering the temperature when you leave or making sudden changes of 3 degrees F or more can make your heat pump work less efficiently.

Always set your heat pump to “Heat” mode in winter. The “Auto” mode switches between heating and cooling by itself, which may not be what you want. If you have a backup heating system, set its thermostat lower than your heat pump’s. This makes sure the backup only turns on if the heat pump cannot keep your home warm enough. Make sure your backup system runs enough in very cold weather to protect your pipes from freezing.

Normal Heat Pump Behavior in Winter

It is normal to see frost on your heat pump’s outdoor unit. This happens when the outdoor coils get below 32 degrees F. Moisture in the air freezes on the coil. When this happens, your heat pump starts a defrost cycle. It switches to cooling mode for a short time. This sends warm refrigerant through the outdoor coils to melt the ice. This cycle usually lasts only between 5 and 15 minutes. It should not make your home feel colder.

Many new heat pumps are designed for cold climates. ENERGY STAR says these heat pumps use special parts to work well even when it is very cold outside. They are tested down to 5 degrees F. They can keep working below that temperature. But if you live where it gets even colder, pairing your heat pump with a backup heat source can heat your home most efficiently.

What You Can Do to Help Your Heat Pump

Keeping your heat pump well-maintained helps it work best. NYSERDA, New York State’s energy research and development authority, suggests these steps:

Heat Pump Homeowner Checklist

• Clean Filters: For ductless systems, vacuum or rinse the dust filters inside your indoor units every month, or when they look dirty. Clean them more often if you have pets. For ducted systems, wash or replace filters in the air handler or return air grille every 90 days. Always check your manufacturer’s guide for specific filter types, sizes, and thickness.
• Clear Outdoor Unit: Keep the outdoor unit free of anything on top of it or around it all year. After it snows, clear away any snow and ice. Leaves, shrubbery, or other items can block airflow. Your outdoor unit needs good airflow to take heat from the outside air.
• Never Cover the Outdoor Unit: Do not cover your outdoor unit in winter. It needs air to flow freely. However, you should protect it from too much snow falling off the roof. You can install it under an eave, under a deck, or use a snow shield.
• Clean Vents: If you have a ducted system, clean the supply registers (where air comes out) and return air grilles (where air goes in) once a year.

When to Call a Qualified Professional

Your heat pump needs professional service to keep running well and extend its life. NYSERDA suggests getting your heat pump checked and serviced as often as the manufacturer recommends, usually every 1 to 2 years. A qualified heat pump service technician can perform these important checks:

• Check that the heat pump has the right amount of refrigerant.
• Look for leaks of refrigerant or oil.
• Make sure there is enough airflow.
• Clean the outdoor and indoor coils.
• Clean the condensate drain pan and check for clogs.
• Inspect electrical parts.
• Seal any air leaks in your ducts.
• Check that refrigerant lines are insulated and protected from the sun.
• Confirm your thermostat settings.
• Check that your supplemental (backup) heating only turns on when it is needed.

If you notice your heat pump is not heating your home well, making unusual noises, or if ice builds up on the outdoor unit and does not melt during defrost cycles, it is time to call a technician. Do not try to fix refrigerant leaks, electrical issues, or coil cleaning beyond simple dusting yourself. These tasks require special tools and training to be done safely and correctly.

How to Hire an HVAC Technician

Hiring the right HVAC contractor is key for good service or a new heat pump installation. ENERGY STAR and the Federal Trade Commission (FTC) offer good advice.

Before You Call

• Know the model of your current heating system.
• Note its maintenance history.
• Point out any rooms that are uncomfortably cold.
• Ask friends, neighbors, and co-workers for names of contractors they trust.

Vetting Contractors

• License and Insurance: The FTC advises you to only consider contractors who are licensed and insured. Confirm their license with your state or county government. Ask them for proof of insurance.
• References: Ask contractors for customer references. Call these customers and ask about the contractor’s work. Find out if the job was finished on time and within the agreed price.

Getting an Estimate

• Home Evaluation: Expect the contractor to spend time inspecting your current system and your home. They should assess your specific heating needs. A good contractor will not just give you a quick quote over the phone.
• Proper Sizing: A bigger system is not always better. The contractor should size the heat pump based on your home’s actual features. This includes your house size, how much insulation you have, and your windows. They should not rely on a simple “rule of thumb.” Equipment that is too large can turn on and off too often, making you less comfortable and shortening its life.
• Ductwork Inspection: If you have a ducted system, ask the contractor to inspect your ducts. They should check for air leaks and insulation. Leaky ducts waste energy and can make your home less comfortable. They should also measure airflow to make sure it meets the manufacturer’s directions.
• Written Bids: Get written, itemized estimates from several contractors. Compare the costs, the energy efficiency of the proposed equipment, and the warranties. The lowest price might not be the best option if the equipment is not efficient, as your energy bills could be higher.
• Sign a Proposal: Always sign a written proposal before any work starts. This protects you by clearly stating project costs, specific model numbers, the work schedule, and warranty details.

When This Advice May Not Fit

This advice is for homeowners with typical heat pump concerns. If you are dealing with a major system failure, or if you suspect a refrigerant leak that is causing health issues, you should contact a qualified HVAC professional immediately. If you notice issues with your electrical panel related to your heat pump, contact a licensed electrician. Never attempt to work on electrical panels or refrigerant lines yourself. If your home has structural damage, or if you suspect issues with lead paint or asbestos, do not attempt to address these yourself; instead, contact professionals specializing in those fields for safe assessment and removal.