271. Heat Pump Noise During Heat
28 Jan 2026 · 4 min
Heat pumps make loud noises during defrost cycles when they reverse into AC mode and activate heat strips to melt frost. It's normal. Avoid switching to emergency heat unless necessary, since it costs much more to run.
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Foreign. Hey, this is Derek Cole, and welcome to the Derek Cole Podcast. This podcast is all about home comfort and energy savings. The majority is really comprised of short audio clips of advice and answers to questions that we've been asked over the years. We also kind of sprinkle in the Ask Derrick Cole show audio, which is a much longer Q and A kind of program. If you like this episode, and I hope you do, I would love for you to share it on social with others. Just take a screenshot of the program and hashtag it Derek Cole so I can see you. But let's get into today's episode. When it goes into defrost and it has to go on that cycle, it actually reverses the flow of refrigerant. So instead of being in heat mode, it switches to AC mode and it turns on those heat strips so you don't get cold in the house. So the reason it makes that loud noise is all that gas and refrigerant is saying back the other way. So that is the noise you're hearing. A lot of folks don't know that and probably don't need to know that, but it's actually going into AC mode because it's burning off the frost on the outdoor unit. So it's actually taking the heat that's in the house and blowing it back outside like it was. Like it was summertime. So that's how you melt that frost. So it does make quite a kind of a loud noise. And especially if it's at the bedroom or wherever the outdoor unit is, it'll probably wake you up, or at least until you get used to it, wake you up. But it's nothing to worry about. And some folks have asked too, you know, when it's really cold outside, should I just turn my unit to emergency heat only? And the answer is no, do not do that. There's still heat in the air. The heat pump can still function with the immersive heat if you go straight to immersion heat, that is three times more expensive than regular heat. So that is not a good option unless that unit is just packed with snow and ice and you can't get to it and can't defrost. And that's a good reason. But to have the unit work less by not having to go to defrost cycle is actually going to cost you more money. So just a little tidbit there, but the noise is the defrost cycle. Well, what did you think? If you found any value in this episode whatsoever, please share it with your friends and I encourage you to also rate and review on this platform. If you want to be really awesome, download the last six episodes, take a listen. It would really help us out with the rankings on this platform. Thank you so much for listening. Please reach out on social if you need any help or we can help in any way, please reach out. Until next time. Talk to you soon.
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