Malfunctions Could Drive Up Your Bill
With the winter season in full swing, it’s a good idea to check your heat pump. You may not even realize it’s malfunctioning until you see that hefty energy bill. Here are ways you can check to see if everything is running smoothly.
Auxiliary Heat
When your heat pump is set to heat mode, check to see if the outside compressor is operating when the indoor air handler is running. If it isn’t, the auxiliary resistance heat will automatically start running to heat your house, which could become expensive.
When your thermostat shows the auxiliary heat (AUX) indicator, your heat pump uses resistance heat strips inside the air handler to warm air. When the heat pump isn’t generating enough heat on its own to reach the thermostat setting, AUX will automatically turn on to compensate. Your house might get warm, but you could be using double the energy.
Some smart thermostats let you set how often you’d like to use auxiliary heat, so you can choose between saving energy, being more comfortable, or a balance between the two.
AUX mode is designed to operate when the indoor temperature is 3 degrees cooler than the thermostat setting. If you have a heat pump, increase your heat setting by 2 degrees at a time to prevent your auxiliary heat from turning on.
Test your system’s efficiency
To determine how well your HVAC is performing, it’s important to know the difference between return air temperature — what goes in your filter grille — and supply air temperature — what comes out of the vents. This is called the “split” temperature, and you can test it using a digital thermometer.
The ideal split temperature depends on the mode you’re using. Test your system’s performance on each setting:
Heat pump only: This is the most efficient setting on your heat pump because it only uses your outside compressor to generate heat, but it only works effectively when the outside temperature is above 40 degrees. The split temperature between the supply air and the air coming out of your vents should be 25 degrees or more.
Heat pump with AUX: At this setting, the split temperature should be about 30 degrees, depending on the amount of resistance heat strips. AUX also runs during the system’s defrost cycle. If the system has to defrost frequently, you should schedule maintenance with a licensed professional.
Emergency heat: This setting should only be used in a true emergency when the heating is malfunctioning, but the weather is cold enough to require heating for not only comfort, but safety.
Because many variables can impact the efficiency of your HVAC, it’s important to have a certified technician perform regular maintenance. They can also help explain how your system works and help you get the most out of it.
