Noise related to hot water solar panel system ?

NB47

We have a hot water solar panel system in our house and there seems to be a constant humming sound throughout the house. Not everyone notices it but it is definitely there and is causing sleepless nights. We have had plumbers and electricians in to try and determine what is causing the noise and have ruled out mains electricity, the heating and mains water supply but now wonder if it could potentially be related to the hot water solar panels we have on the roof ? The solar system is a closed loop with a hot water tank upstairs and the panels themselves located slightly higher on the garage roof with the connecting pipes running through the loft. I have noticed a small leak in one of the pipes connecting to the hot water tank itself and wonder if this is causing a constant flow through the loop which might be causing the noise or if anyone else had any other ideas of things to check. The noise itself is like a low revving car engine, if this helps at all. Thanks in advance.

graememk

The only moving part on a solar tube system is the pump and that shouldn't be going 24/7.

Mine I can hear the controller click on and off on a good day and can hear the pump running.. just about.

If you turn it off, does the humm stop?

If you turn everything off does it stop?

DC999

https://www.boards.ie/discussion/2058296667/noise-related-to-hot-water-solar-panel-system

Have you turned off the fuseboard switches one by one to see does it disappear? Would help find out what it is.

If it's a semi detached it could be from your neighbours. They may have something run 24×7.

Compressor (motor) in a fridge or freezer would vibrate and make a noise. Heard of freezers with faults and compressor stayed on all the time.

Or a pump that is running for your water or solar thermals or something else.

Could it be outside and coming in? We live beside a busy road and get vibrations thru the house when heavy trucks go past. And a constant humn from traffic.

Could it be a pest deterent in a neighbours? Electronic device that runs all the time. My foxes have one that is supposed to stop foxes. I can hear it clearly. They can't.

When is the sound not there? Might help rule stuff out.

NB47

https://www.boards.ie/discussion/comment/120603842#Comment_120603842

thanks, yes we've tried turning the system on and off and the noise still persists. The water in the house runs through a pressurised system so the noise isn't necessarily the solar system, it's just that we've tried everything else and no success in preventing the noise, so thought on the off chance it could be related.

NB47

https://www.boards.ie/discussion/comment/120603888#Comment_120603888

yes, we've tried the fusebooard switches. ESB have been out and disconnected the house from the mains, and and Irish Water have been out and checked for links and no success there either. We live in a detached house with nearest neighbours about 20 metres away and they can't hear anything. The noise is only audible internally which kind of lead us to thinking it could be water related out, the only avenue not thoroughly explored is the solar system but perhaps it is completely unrelated.

oaklands

The water pumps on your hot water (not solar) I believe is activated when the pressure drops. So the leak you mentioned could be causing this to happen over night. Actually you likely only notice at night time because everything else is quiet.

Try disconnecting your house water pump(from mains) over night to see if it goes away. If so, the solution is to fix any leak or drips from taps or toilets etc.

Search for Intermittent Water Pump Cycling for more info

NB47

https://www.boards.ie/discussion/comment/120604019#Comment_120604019

thanks, we have low water pressure in the house so have a mains water pump to ensure we have pressure upstairs. It is quite sensitive and very loud (!), we've had a plumber out already as the pump was triggering quite frequently and have resolved that issue. Unfortunately it's a separate noise. I think the next step is to get an acoustic assessment to pinpoint the cause.

NB47

Hi, just a couple of follow up questions in regard to this. The pressure gauge running of the immersion tank is just under 4 bar, in a closed loop pressurised system, is this too high, I have read that around 1.5/2 bar is about average ? Also, there are 6 pipes running to/from the tank all of which are piping hot, I assume this is the norm ? Thanks again in advance.

Yellow_Fern

If you get air in your system, it can get very noisy.

graememk

https://www.boards.ie/discussion/comment/120683272#Comment_120683272

6 pipes? from the tank?

All go to the solar?

A coil for oil, coil for gas, coil for solid fuel?

4 bar does seem a bit high but wouldn't be dangerously high.

dumb_parade

Check the temperature probes that are connected to the tank, they got pulled out in the past and the controller kept the pump running continuously

NB47

https://www.boards.ie/discussion/comment/120684204#Comment_120684204

I think it is a looped system so hot water goes to/from the cylinder.

jbcip

Did you ever land on an answer here? I live in relatively new build, detached (rural), no solar heating, but do have a consistent humming sound that I find is pretty much 24/7 now but more noticey at night. It is causing sleepness nights.

My wife doesn't seem to hear it.

It's tough going