HVAC units produce unexpected rattling noises
90 posts across 6 communities in the last 30 days; 88% from r/hvacadvice.
“I switched from oil to natural gas. They just did a conversion of my oil burner and had to install a new chimney liner. Now when the furnace kicks in for heat or my indirect water heater there a strong whoosh then vibrating of thr chimney. Its strong enough to shake the wall…”
“Just had to put my LG AC back in the window due to a late warm spell, and it’s making this weird intermittent rattle when the compressor is on. It’s relatively quiet, but in the dead of night, it’s driving me nuts. Any idea what this might be? I’ve tried pressing on various…”
“Hi everyone, I have a Modine Hot Dawg 45,000 BTU heater that’s making a rattling noise on start up that wasn’t there last year. There were some issues with the initial installation, so I’m following up with the installer to have it inspected and make sure everything was done…”
Multiple users are experiencing unusual rattling or loud sounds coming from their HVAC systems, both new and existing. They seek advice on identifying the cause and potential solutions, ranging from DIY fixes to professional assistance.
SOURCES (60)
“Hello everyone, I recently noticed this loud noise coming from my unit that was installed 3-4 months ago. It’s been happening for a couple of days. Still under warranty so it should be covered but I was hoping I could get some information. Maybe it…”
“AC cools fine but idk if the noise it makes is normal. Just wanted to check if this is ok. submitted by /u/invertedknife [link] [comments]”
“Hi all. I just turned on my heat for the first time this season and I'm noticing this squeaky kind of sound that occurs every few seconds. The sound stops when I turn off the heat. Any idea what this might be? submitted by /u/Final-Resolution-285 [link] [comments]”
“I switched from oil to natural gas. They just did a conversion of my oil burner and had to install a new chimney liner. Now when the furnace kicks in for heat or my indirect water heater there a strong whoosh then vibrating of thr chimney. Its strong enough to shake the wall behind. When its heating our home heat (baseboard) the initial vibration is strong then reduces the subsequent times it kicks in. Is this normal or something I should be concerned about. Its really loud and annoying. Both th”
“Can someone tell me if this is normal? The unit is unusually loud and seems unstable. https://www.youtube.com/shorts/sqXAJxxkB3w submitted by /u/Wise-Ad5640 [link] [comments]”
“Just had to put my LG AC back in the window due to a late warm spell, and it’s making this weird intermittent rattle when the compressor is on. It’s relatively quiet, but in the dead of night, it’s driving me nuts. Any idea what this might be? I’ve tried pressing on various parts of the unit, checked the filter, checked the window sashes…nothing changes it, so I can only assume it’s coming from inside the unit. Help? submitted by /u/JorgeAndTheKraken [link] [comments]”
“Hi everyone, I have a Modine Hot Dawg 45,000 BTU heater that’s making a rattling noise on start up that wasn’t there last year. There were some issues with the initial installation, so I’m following up with the installer to have it inspected and make sure everything was done correctly. Based on the sound, I’m wondering whether there’s an issue with the inducer fan or its blade, but I’m not sure. Has anyone had a similar rattling noise with their Hot Dawg? What ended up causing it, and is there a”
“Hi all This is a Mitsubishi electric mszBT20vgk on wall brackets with anti-vibration dampers. The unit is in cooling mode and after a while, it makes this metallic grinding/cracking noise. I can't quite figure out where it's coming from. I haven't taken off the casing yet to inspect further, as I need to set up scaffolding first to safely reach it. Has anyone here experienced this sound before? submitted by /u/Smotjekitn [link] [comments]”
“Is it normal for a 5ton Goodman unit to sound like this? It’s 9 years old has gone through 2 caps and a fan motor. submitted by /u/nvguy2121 [link] [comments]”
“Its a new unit (3 months old) but first time hearing this intermittent noise. It comes and last a short period and goes. Does anyone knows what might be the cause? submitted by /u/Alternative-Habit894 [link] [comments]”
“I’ve recently started daily driving my 04 explorer again and it seems like the blower motor is super loud. It’s the fancy climate control thing and with it on the 2nd setting is really loud. Any higher than that I can’t hear myself think. Wasn’t an issue when I was just occasionally driving it. I replaced it not too long ago and it was still loud. I know the fresh air door is usually an issue but I have it propped closed so it’s always recirculating. I do have a new door was just waiting on it t”
“It's a haier air conditioner, heard a singular thump noise, not like a long thump noise just a short bang noise inside it then it started shaking, its making the window shake for some reason along with it, never done this before, had the air conditioner for a year, is it safe to leave it on, I don't know anything about fixing ac units or air conditioning, I can assure you its shaking it just doesn't look like it from the camera for some reason submitted by /u/Familiar-Roc”
“Hey gang, there is a high-pitched whining noise coming from my oil burner (or at least, it seems to be coming from it). Clearly audible around the 10-second mark in the video. Any ideas what's going on? The oil burner is a Beckett AFG. Thank you! submitted by /u/quicksandhayabusa [link] [comments]”
“Hello! I have the York model CMB03011. Back in August this machine threw a blade and was shaking violently, opened it up and replaced the blade and it has worked fine and quietly for two months. The original blade was “winged” or had a different shape and was pointy, while the new blades are smaller. After the replacement however it worked fine and made no noise or vibrations until now. Since last week it’s been making this rattling noise. I have since cleaned out the vents/coils, opened it up a”
“Hi, I've got a new Lennox high-efficiency (not the highest high), multi-speed heat pump. When it's cooling it makes a metallic, raspy, slurping sound - I've captured it in the attached video. The installers says it's normal but I don't buy they were 100% confident. They claimed that with the unit running in low speed/pressure mode, this sound is normal. Anyone have experience with this? submitted by /u/mgstauff [link] [comments]”
“Hello, Can someone tell me why my unit is so noisy? It's making me crazy 😵💫😂 I had a professional come and check it... He put grease on a wheel and told me it would get better. If not, to call back. 112$ down the drain 😭 The unit is cleaned every year. It's always noisy, even on low, cold or heat. Thank you very much 🧡 submitted by /u/Marion_Den [link] [comments]”
“It’s a bedroom on the other side of the wall, so I wasn’t sure if it would be too noisy. It’s a Daikin unit if that matters submitted by /u/UsedBoard [link] [comments]”
“Just had a new system installed yesterday, a Carrier 27vna3 (3 ton) with fe5b (4 ton). I've noticed that the liquid line is noisy compared to the old system which I never could hear that, and now it also gets cold to the touch. I know the AHU has a TXV and the condenser has an EEV/EXV. Would that make any difference? Or is something quite wrong? When they tested it, I am showing suction as 121.7 psig 71.3f temp 46.7f vapor saturation 24.6f actual superheat and liquid at 258.7psig 84f temp 89”
“We just got this unit installed in late July and it’s been making this weird crank like sound and maybe I’m just thinking it’s getting louder, but I’m not sure if this is a normal sound submitted by /u/Mo_Maha1755 [link] [comments]”
“Just changed my capacitor few weeks ago. I did notice my condenser sounds louder these days. Does this sound unhealthy or am I overthinking it? submitted by /u/Worldly_Green_7021 [link] [comments]”
“I turned my gas furnace on for the first time this season and I caught this video of it. I’ve already got a guy coming for a tune-up, should I see if he can come sooner? Just trying to figure out what it may be, if it’s a good idea to run it, and if I need to get someone sooner. For reference, as soon as I turned on the thermostat I started hearing this sound. The clicks happen for 30-45s and get quieter and less frequent after that and eventually stop altogether. The furnace still heats fine. I”
“This air conditioner on the side of our building has been making noise and vibrating a lot during both hot and cold seasons. I'm wondering if anyone might know what's going on with it? Whether its stuffed or just needs a service. Link to video: https://imgur.com/a/vulRrG5 Thanks! submitted by /u/Main-Sector5306 [link] [comments]”
“Hi gang, hoping someone can point me in the right direction with a noisy vent motor. It seems like the whole system ("SS1 Sideshot Vent System" by Tjernlund ) is discontinued so I am hoping I can get in there and (hopefully) patch things up. I have had it looked at professionally, but for some reason or another, no one seems to want to bother with it. I am fairly handy so wouldn't mind lubricating a bearing or two, or if it comes to it, swapping out the motor. Thanks a lot! s”
“My AC tech changed the contactor and now started making this noise. Is it bad? What could I do? submitted by /u/NoPaleontologist2872 [link] [comments]”
“I starting hearing this noise inside my basement about couple days ago but didn’t realize it came from the outdoor unit until tonight. Cooling still works inside the house and the unit is keeping the temp down. Thanks. submitted by /u/sayamilky [link] [comments]”
“Just had my condenser fan motor replaced. Old carrier unit from 2007 and they replaced with this motor https://www.grainger.com/product/4M226?RIID=70534816215&GID=&mid=OpenOrders_OrderCancellation&rfe=&gucid=EMT:10549419:Item:CSM-322&emcid=NA:Item Old Motor was a GE 5KCP39KF 1/4 HP also has AB36BS on label. It sounds horrible at startup and has a rhythmic sound when running. They used a 5 MFD capacitor on it but just doesn't sound right. All the screws along the shrouding”
“I lived in the bay for a while where the houses never had AC but since I moved inland every house basically needs a central or window AC. I’ve had this sound come out of my AC basically ever since the owner replaced it in my apartment but I never really knew what an AC is suppose to sound like. Its so loud that its been giving me headaches for a year now. It makes this noise at 5 minute intervals when its on. The last 4 seconds in this video is when the noise stops. submitted by /u/J”
“Hey HVAC experts. I have a Bradford White tankless (RTGS199N1) (NG). For awhile now when it starts up there is just this super loud “squeal” for a few seconds, which then stops once it gets going. I decided today I was going to actually figure this out after ignoring it for months (a year??). :) I assumed it was a pipe outside the unit that was just vibrating but it turns out it is coming from inside the unit on the left side where the gas comes in. I tried a few things: (1) if I turn the unit o”
“My air conditioner recently started making this noise almost constantly, even when the AC is off. The only way to make it stop is to turn off the breaker. The guy my landlord sent says there's nothing to fix, it's just like this. Is there anything that can be done? It is driving me insane! Thanks in advance to anyone who can help! submitted by /u/summoningdark177 [link] [comments]”
“I bought a house with a older heat pump. I had my furnace inspected before turning it on. When they turned on the heat pump, it made an extremely loud sound and the tech said it was a valve or something, i cannot remember. The unit is from 2012 and the tech said they wouldn't be able to find replacement parts to keep it running. is this true? The tech said this was a base model no name furnace and heat pump and told me to call when it goes out. Took measurements for a quote. submitted”
“I just moved into this brand new build 6 months ago and every time the AC turns on this rattling noise runs and stays constant until it turns off. I have a 2 story 2600 sq ft home. submitted by /u/TheTiredGuy1 [link] [comments]”
“Freezing today where I am and turned on the heat and it's all the sudden making this god awful sound. Just want an idea of what to write on my work order submitted by /u/Zombiecondie [link] [comments]”
“Every time the burner shuts off, the plate slaps shut. It doesn't sound like much in the video but I can hear it throughout my house. Is this normal or can it be adjusted? submitted by /u/Redditstar101 [link] [comments]”
“Title says it all. It isn’t very loud. I had to get my phone very close to hear it. Indoor air handler installed in our garage. We change the filter regularly. submitted by /u/onthadontrary [link] [comments]”
“We already had someone clean it. The sound was gone for maybe a week and the noise came back. What could be the issue? TIA! submitted by /u/bumbumpa0 [link] [comments]”
“If anyone can help it would be appreciated. My air handler was working fine then it started to make this sound all of a sudden. It sounds really loud when on so its been off since. submitted by /u/Shot_Butterscotch704 [link] [comments]”
“Recently had a company come out to look at my ac and they said they topped off the refrigerant. Now I’m noticing a water like sound in the lines when it’s running and a gurgling sound when it turns on/ off. Should I have them come back out or are these sounds normal? submitted by /u/Yodayodayoda7 [link] [comments]”
“6 months old ML series 3.5 tons. Seems like it got louder recently but wanted to see if this sounds normal. Measured about 77 decibals. Much louder than my other unit behind it. submitted by /u/BountifulRegrets6969 [link] [comments]”
“As title states, HVAC techs have been here a few hours now and can't figure out how to make it stop. I have an indoor electric only furnace. The coils needed a good deep clean, and they pointed out the prior owner of my condo likely never had the coils cleaned, ever, literally in years. The coils were cleaned, airflow is crazy good now, but now there is a very horrible whistling sound coming from the furnace ONLY when the filter is put in. We have the correct size filter. They can't figu”
“Loud grinding sound from furnace? submitted by /u/ParkingVariety9062 [link] [comments]”
“Any ideas Thinking it could be a bearing submitted by /u/sleepaccount1111 [link] [comments]”
“Hi! I just moved into a new apartment with baseboard heat. I turned it on for a moment to test it (it worked) for a minute or two and then turned it off. A couple hours later and it’s making a nonstop water dripping/crackly/ticking noise in the wall about 6 inches above it. I turned it back on and off again and it didn’t stop the noise. Almost sounds like rain and it’s drizzling out, but this wall is facing the inside of the apartment? Should I be concerned? Does it sound electrical or like it c”
“Hi all, My HVAC Outdoor unit is now making this sound when thermostat signals it to turn on. It's a little bit loud. AHU cools well, so no issues there. I also know that my refrigerant level is good. What do you think is causing this noise? Other AC's in my community, which are the same don't sound like this, and they're all the same age. It's a Lennox Unit. submitted by /u/taraowu1212 [link] [comments]”
“I ordered the fan...then I noticed the noise coming in when we weren't running water. I disabled the recirculation timer so it was set to never turn on and the noise went away. Stupidly I didn't return the fan....today I turned back in the recirc timer because it's getting colder and as soon as the first time set came around the noise came back! It is probably the recirc pump which nobody ever mentioned, soni have a new fan i can't return and have to figure out if I can do the pu”
“Sorry for my English... Please advise. We moved in to a house built in 1980s. The compressor is like jumping starts in the video, while the fan outside is constantly working during these jumps. And this only occurs when the room temperature is close to the set one, for example, I set to 79, and AC works fine until the room cools down on 79 degree then the AC will have this issue. submitted by /u/IllLunch9369 [link] [comments]”
“Just started about 3 days ago. Have had the unit for 3 years with normal-low usage. It’s this round piece I’m focused on where the tick is coming from. submitted by /u/Greentrader208 [link] [comments]”
“About 1 weeks ago our air handler was making this noise and no air was coming inside the house. So today 2 HVAC technicians came today to do a diagnostic and found nothing wrong which I’m confused about because before they came I try using thermostat yesterday and it was making this noise. They open up the air handler, ran a couple of test and turn on the thermostat and everything is working perfectly fine. They also check the ac condenser, ran a couple of test and they say everything is fine. T”
“Hello i've been hearing this hissing sound for over 2 week, i had complex mentenance 3 times (every time they said they fix it) , is this normal? Is it refrigerant leaking or just water? The sound is there 24/7 even if i dont have the AC on. I had it 2 days completly off and the sound was still there. Please help me with advices and what is the problem. submitted by /u/Emotional_Letter4181 [link] [comments]”
“Recently moved into this rental and the AC just started screaming at me! I tried turning it off for a bit and as soon as it turned back on it started screaming again. I have no idea what I’m looking at and was wondering if there’s anything I could do or take a look at. Any help would be appreciated. submitted by /u/PaulDog13 [link] [comments]”