HVAC Noise Diagnosis & Cure FAQs-3

Wooing Sounds from HVAC Systems, FAQs

Wooing sound coming from new rheem AC 14 seer non variable speed.

What is cause of wooing sound coming from new rheem AC 14 seer non variable speed. On 2018-10-16 by Alex

Reply by (mod) - wooing sound of air conditioners

Gee, Alex, I honestly don't know. Could you describe "wooing sound" a bit more. Surely the AC isn't making affectionate noises.

See HVAC NOISE-5 SCREAM SING TRUMPET WHINE WUWU - scream, sing, squeal, trumpet, water sounds, whine, whoosh, whistle, wuwuwu, or silence

for more detailed diagnostic advice.

Water Sounds from HVAC Systems, FAQs

Rushing water sound from floor vents

My townhouse has floor vents, the first few vents closest to the A/C Unit have a very loud rushing water sound coming from them. Like loud enough that it sounds like a rushing stream lies beneath my floors.

Our largest unit, is a 50 pint and it produces anywhere from 150-250 pints of water per day.

I'm still training in Home Inspection and i'm stumped on the water running sound. My landlord isn't very quick to respond to problems here, so that further complicates things.
Any suggestions on the running stream noise? On 2018-08-12 by Ryan S -

Reply by (mod) -

Check and tell me if they're running water sound is associated with refrigerant piping

Reply by Ryan S

No sir, I opened the HVAC closet and no noise like that coming from refrigerant piping.

Another thing I just noticed, when you open the HVAC closet, you get a rush of freezing air coming out, like that closet is super freezing. And the air coming out of the vents isn't near as cold.

Reply by (mod) - Flowing air doesn't sound like running water

I'm baffled myself Ryan. Flowing air doesn't usually sound like running water - perhaps there is something loose in the ductwork.

Or for my best guess: if it's not a fan noise then you could be hearing condensate running down a disposal drain.

Knocking Sounds from HVAC Systems, FAQs

Knocking sounds at our heat pump air handler

Just had new air handler put in attic for heat pump system. Sometimes now when unit shuts off we hear like a knocking in the wall. It is like the pipes are knocking. It happens in the later afternoon. On 2019-05-29 by Pat -

Reply by (mod) -

I posted your recording at

HVAC NOISE-2 CHATTER CLANK FAN GROAN - chatter, clank, clunk, cyclical sounds, fan noise, groan, growl, gurgle sounds

under "clanking" sounds - please take a look.

Knocking sound from Trane air condidtioner

Trane AC is a little over a yr old and makes a knocking noise after it shuts off. On 2018-04-24 by Ruth

Reply by (mod) -

Ruth

Watch out: I'm a little concerned with the noise you're describing could be due to liquid slugging which can damage the compressor. I would prefer to turn the system off and call your service company for an inspection and repair.

See also

BANGING NOISE at AIR HANDLERS or in DUCT SYSTEMS

Let me know what you're told and I may be able to suggest follow-up comments or questions.

Whistling Noises at HVAC Systems, FAQs

Loud whistle noise at the compressor side it starts

Hello guys!
I got a 4ton unit that is making a whistle noise at the compressor side it starts after like 10min from starting the ststem but it doesn't shut the ststem off, it sounds like the safety valve on any compresor

i can hear a small whistle, if i shut off the system and wait a minute or 2 i turn it on and it goes away for another few minutes!

My question is if this is a sign of a problem or its normal? If this is a problem what can i look for? Thanks in advance for any help given On 2017-05-21 by Angel

Reply by (mod) -

Angel

Whistling is often a problem at an expansion valve or sometimes a more serious overpressure problem at the compressor.

We discuss the common causes (and cures) for whistling noises at an A/C compressor in HVAC Noise Group 5 at https://inspectapedia.com/noise_diagnosis/HVAC_Noise_Descriptions_5.php please take a look and then don't hesitate to ask for more help.

Daniel

Whooshing or Wind Noises at HVAC Systems, FAQs

Builder says whooshing fan noise is caused by "wind gusts" getting in the vents

Moved into new construction 3 floor SW facing condo and have an intermittent, "fan like" noise which is unpredictable , lasts precisely 12 minutes, is not related to fans being on or off, is located in the ceiling area of the dining room on north side of condo and is heard in next door condo .

Builder says it is caused by "wind gusts" getting in the vents and there is nothing he can do about it.

He has never heard the sound. The noise does not necessarily occur when it is very windy , when it is colder and is not heard when the fans are turned on in the condo

What is this? On 2017-02-24 by Anonymous

Reply by (mod) re: wind gusts as sources of regular-interval building noises

Anon

I would look again at mechanical systems. It's just not reasonable that wind gusts would occur at regular intervals and be of regular lengths.

Rattling Noises at HVAC Equipment, FAQs

Rattling Noise at Fujitsu Split System

I have a Fujitsu split unit in my garage. Recently it has started making a rattling noise on the wall unit. It will go away while I touch it on the side (actually on a piece of plastic) but when I let go, it makes the same noise. It will eventually go away for a while but then happen again. I don't see anything loose on it. Please help. - On 2016-08-12 by Anonymous

Reply by (mod) re: popping, rattling, roaring, rumbling, running water sounds from air conditioners

Anon you will find some diagnostic help at

HVAC NOISE-4 POP, RATTLE, ROAR, RUMBLE - loud start, popping, rattling, roaring, rumbling, running water

• LOUD NOISE at STARTUP then quiet HVAC equipment
• POPPING or POPCORN noises - turn off the system immediately
• RATTLING & VIBRATION noises from A/C or Heat Pump System
• ROARING NOISE from A/C Compressor/Condenser unit
• RUMBLING NOISES A/C compressor/condenser or blower fan motor noise
• RUNNING WATER sounds in refrigerant piping - floodback or condensate?

where we discuss causes and cures of rattling noises.

What you describe might just be a loose part, or on the other hand, a motor that's vibrating (and on the way out) could be shaking the outdoor unit.