This time of year always brings questions and concerns from heat pump owners. If you use a heat pump to heat your home, you may have experienced some “odd” traits that leave you wondering whether your system is performing as designed. The frequently asked questions below represent most of the concerns that we get during the winter months. If you have additional questions, please don’t hesitate to call or email us.

Frequently asked questions about heat pumps during the winter months

Q        Should my outdoor unit be running during the winter?

A       “Yes”- if you have a heat pump or a dual-fuel system. “No” if you have a gas furnace or straight electric heat.

Q        Sometimes I see ice on my outside unit. Is this normal?

A       “Maybe.” It is common for a small amount of frost to accumulate on the outside unit during the heating cycle. You should never see a large accumulation of ice. If you do see ice, leave the unit running for about an hour. This will give the system time to go through a defrost cycle. If the ice persists, you most likely have a problem with the system and should have a technician perform a diagnostic evaluation.

Q        Sometimes my system makes strange noises, the fan motor outside cuts off and the unit starts smoking. Is this normal?

A       “Yes.” This describes the normal series of events when a heat pump is going thru its defrost cycle. During this cycle, the system is actually reversing into the AC mode to heat up the outdoor coil and melt away any frost that has accumulated. Your heat strips (aux heat) will power on to re-heat the cold air that is being created during this cycle and therefore provides constant heat for your home. Oh… and it’s not really smoke that is created, it’s actually steam from the melting frost.

Q        Why do I sometimes see “aux heat” on my thermostat and is there a way I can turn it off?

A       It is normal to see this indicator occasionally. The auxiliary heat will power on during a) the defrost cycle, b) when you raise the set point on your thermostat more than a few degrees at a time, and c) and on extremely cold days as a supplement to the heat pump. You should not attempt to turn off this feature. It is true that more power is consumed by the system when the aux heat or “heat strips” are on because the system is creating heat instead of just moving it as when the heat pump is providing heat. To minimize the use of the aux heat, you should a) leave the set point at a constant temperature instead of making changes of more than a couple of degrees, and b) have your heat pump serviced annually to make sure that it is operating at its peak efficiency. For example, if your system has a problem, the aux heat will power on more frequently to provide heat and you may never know it… well not until your power bill comes that is.

Q        What is emergency heat? Should I use it? If so, when?

A       Emergency heat is simply your heat strips. If you switch your thermostat into the emergency heat position, the system will turn off your compressor (outdoor unit) and use only the electric heat strips to provide heat. This is a built-in safety feature so that you can heat your home if your system experiences a failure with the heat pump. You should test your emergency heat at the beginning of every heating season.

Q        Sometimes the air coming out of my vents feels cool. Why is this?

A       Heat pumps provide heated air to your home at around 90° F. As the temperature outside falls, the temperature of the air being delivered to your home will also fall slightly. While this is still warm enough to heat your home, it will “feel” cool to you because your body temperature is actually higher- around 98° F.

Q        How often should I change my filter in the winter?

A       The season does not matter. Change your filter once a month.

Q        What is the fan switch (or button) for? What is the difference between “Auto” and “On”?

A       Almost every thermostat will have this feature. When you have the fan in the “Auto” position/mode, the fan will cycle on only when the system is heating or cooling. When the fan is in the “On” position/mode, the fan will run continuously, regardless of whether the system is heating or cooling. It is not recommended to run your fan in the “On” position in our area because it will make your home feel drafty in the winter and will introduce excessive humidity during the summer.

Q        Should I have my system serviced before winter, summer or both?

A       Good question. Newer systems do not require as much maintenance as older ones do. This is because the newer systems have oil-less motors and fewer moving parts that require attention. Basically, if your system is less than about 8 years old, an annual maintenance is sufficient. During a once-per-year maintenance, we will check both the heating and cooling components. If your system is older than 8 years, then it should be maintained twice per year. Just like a car, regular maintenance will keep your system running efficient and reliable as well as help prevent untimely breakdowns.  Remember if you have a new system it is extremely important to have maintenance performed at least annually because failure to do so will void almost every manufacturer’s warranty.

Ultimately, if you are unsure of whether you need service… call us. We will be happy to schedule an appointment with you and provide an evaluation of your system. According to Energy Star, routine maintenance could save you 10% on your power bill.

Reeves Heating & Air Conditioning
910-791-1004