navitron
 
Renewable Energy and Sustainability Forum
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Anyone wishing to register as a new member on the forum is strongly recommended to use a "proper" email address. Following continuous spam/hack attempts on the forum, "disposable" email addresses like Gmail, Yahoo and Hotmail tend to be viewed with suspicion, and the application rejected if there is any doubt whatsoever
 
Recent Articles: Navitron Partners With Solax to Help Create A More Sustainable Future | Navitron Calls for Increased Carbon Footprint Reduction In Light of Earth Overshoot Day | A plea from The David School - Issue 18
   Home   Help Search Login Register  
Pages: [1] 2   Go Down
  Print  
Author Topic: Combi/condenser Boiler upgrade noise problem.  (Read 38630 times)
Big Wal
Newbie
*
Offline Offline

Posts: 20


-- -- -- -- I SEE -- -- --


« on: October 18, 2011, 11:54:04 AM »

 help Just had a boiler upgrade, having vibration and noise from a number of radiator temp control units on each.
Have screwed down each open close supply valve to each radiator to trickle but find that I'm getting the vibration noise when the thermostat cuts in to warm the house. Can the team help Walter.
Logged
w0067814
Full Member
***
Offline Offline

Posts: 239


« Reply #1 on: October 18, 2011, 12:08:40 PM »

I have a Worcester Bosch combi that also makes a vibrating noise. In my case it is when the boiler is running at a low modulated setting (which is most of the time - only when the heating first comes on and the house is cold does the boiler run at full tilt) I get a vibrating noise from the boiler itself. The noise is amplified by the masonry wall to which it is attached - acting like a sounding board. If I go into the loft and sit next to the boiler you can barely hear it. There is nothing wrong with the boiler - it's just the way that it is designed in my case.

I think (guessing) that it is to do with the way that the pump speed is regulated by pulsing it with electricity, and it is these pulses that I am hearing. I've tried manually over riding the pump speeds, but to no avail.

I wonder whether your problem is the pump speed control too, but in your case your "sounding board" are the radiator values as these are the first point of resistance that the circulating water hits causing a slight water hammer effect?

When I finally turn the boiler on this winter I can look forward to waking up at 5:30am everyday when the heating kicks in. Quite annoying, but unless I fit the whole boiler on isolating mounts there isn't much I can do.

-Tim
Logged
M
Hero Member
*****
Offline Offline

Posts: 5394



« Reply #2 on: October 18, 2011, 12:20:00 PM »

Can I add similar issues. I have a Worcester combi, fitted 12 years ago.

Problem 1 since install, the thermostatic radiators valves whistlee. They do this as they are trying to close, so if room is colder than setting they are open and don't whistlee, or when warmer (ie I've got annoyed and dialled them down a bit) they are off and silent, but when close to shut off they whistlee. Spoken to no end of plumbers and none have ever heard of it. I can partially resolve, by restricting pressure via the on/off valve, or by lowering the pressure on the boiler. A plumber friend recently mentioned that he saw a bottle of 'whistlee reducer' in the plumbers merchant, but he may have been pulling my leg.

Problem 2, only started last winter, I too am getting that masonry drilling noise from boiler and wall. Only does it occasionally and only for about 2 mins at a time. Plumber friend and I took case off boiler, but hard to work out where it is coming from, he reckoned the pump too, but vibration noise is a tricky one to work out location. As it tends to only do it for a day or so after pressure has been changed (up or down) I've left it as spending money might be a waste given age of boiler.

Any thoughts? Big Wal, what boiler have you got? Is it just a coincidence that Tim and I have Worcester's?

Martyn.

Edited to whistlee's to prevent little  whistlie appearing.
« Last Edit: October 18, 2011, 03:51:18 PM by M » Logged

Just call me Mart.     Cardiff: 5.58kWp PV - (3.58kWp SE3500 + 2kWp SE2200 WNW)
ericw
Hero Member
*****
Offline Offline

Posts: 774


« Reply #3 on: October 18, 2011, 12:48:12 PM »

It might be worth checking that the flow through the valves is in the correct direction (usually marked on the valve)
Logged
tz0c0s
Full Member
***
Offline Offline

Posts: 143


« Reply #4 on: October 18, 2011, 01:11:40 PM »

A correctly set automatic bypass will help your problem, TRV direction is a good call also.

Regards Andy
Logged
w0067814
Full Member
***
Offline Offline

Posts: 239


« Reply #5 on: October 18, 2011, 03:48:52 PM »

I should say that my Worcester Bosch is a CD30i and was fitted new in 2008.

The sound is definitely the boiler, not the valves in my case. I can control how hard the boiler is working by altering the target water temperature on the front - if I turn it up a notch, the boiler stops modulating and goes full chat - the vibrations go away until the new target temperature is reached. Similarly it goes away if the hot water is run as the boiler runs at full chat with the tap wide open.

-Tim
Logged
M
Hero Member
*****
Offline Offline

Posts: 5394



« Reply #6 on: October 18, 2011, 03:59:06 PM »

A correctly set automatic bypass will help your problem, TRV direction is a good call also.

Regards Andy

Checked flows through valves, even recently replaced all TRV's with a newer model, no improvement.

Interested in the remark about automatic bypass. When the problem first started on day 1 it was incredibly loud. The original plumber came back and changed the tails he left on my request for future radiators in loft and conservatory. He connected the tails up, creating two new bypasses. this improved the situation a lot, but didn't cure it.

I knew that the Worcester's (mine is a 28CDi) had an inbuilt bypass, but didn't know it was adjustable. This sounds very promising. How is it adjusted, or is that a bit too complex for the forum?

Thanks

Martyn.
Logged

Just call me Mart.     Cardiff: 5.58kWp PV - (3.58kWp SE3500 + 2kWp SE2200 WNW)
Big Wal
Newbie
*
Offline Offline

Posts: 20


-- -- -- -- I SEE -- -- --


« Reply #7 on: October 18, 2011, 04:28:47 PM »

Hi Team of knowledge.
Thanks for all your suggestions, just a little of history. Previously the boiler was a Worcester Com-bi had no problems what so ever or with the radiators either. Because it was 17 years old we replaced with a Ravenheat Condenser Com bi series 780, and now that we have the central heating radiators on from this last week we are getting this hammer type noise from the thermostat valves as soon as heat gets to the radiator temp control valve, you turn setting up or down the slightest it stops over to the team.
Logged
Big Wal
Newbie
*
Offline Offline

Posts: 20


-- -- -- -- I SEE -- -- --


« Reply #8 on: October 18, 2011, 04:37:04 PM »

PS banghead
 Flow of water comes in from the left to the right on all radiators temp control is on the right they are WESTHERM valves.
Thanks team.
Logged
greentangerine
Sr. Member
****
Offline Offline

Posts: 421


Osmington, Dorset


WWW
« Reply #9 on: October 18, 2011, 05:29:30 PM »

I had a water hammer problem when I moved into my current abode 10 years ago. 

Traced it to one of the TRVs in the house being fitted the wrong way around;  resolved this and the hammer went away.
Logged

2.940 kWP (Sharp ND210/Solis 4G 2.5)
2.115 kWP (Kinve KV235-60P/SB1600)
2.000 kWP (Sharp ND250/SB1600)
65 x 58mm SunnPro/Torrent T280 RE OV/SunSpeed2 205
11kW Dean Forge Croft Clearburn 10,000 BTU
SoFar ME3000SP /Pylon US2000 19.2kW
myenergi eddi
Big Wal
Newbie
*
Offline Offline

Posts: 20


-- -- -- -- I SEE -- -- --


« Reply #10 on: October 24, 2011, 03:54:16 PM »

Problem solved . Undecided
Gentleman who did the Boiler upgrade to the new one, returned to fix problem. The TRVS knock was due to the flow of water to the radiators being the wrong way he thought the TRVS were dual flow. Sitting here now with  wackoteapot a cup of Tea, sorry mug of tea and not a knock to be heard.
Thanks to all who gave their experience and knowledge freely.
Walter
Logged
garethpuk
Full Member
***
Offline Offline

Posts: 175


« Reply #11 on: October 25, 2011, 11:46:25 AM »

Good to hear its sorted Smiley

A bit late for this but I know of two people with the same problem - both cases were different plumbers and both installed the new boiler with the flow / return the opposite way to the old boiler, neither had checked the TRV's.

Logged
M
Hero Member
*****
Offline Offline

Posts: 5394



« Reply #12 on: February 06, 2013, 07:55:53 AM »

Can I add similar issues. I have a Worcester combi, fitted 12 years ago.

Problem 1 since install, the thermostatic radiators valves whistlee. They do this as they are trying to close, so if room is colder than setting they are open and don't whistlee, or when warmer (ie I've got annoyed and dialled them down a bit) they are off and silent, but when close to shut off they whistlee. Spoken to no end of plumbers and none have ever heard of it. I can partially resolve, by restricting pressure via the on/off valve, or by lowering the pressure on the boiler. A plumber friend recently mentioned that he saw a bottle of 'whistlee reducer' in the plumbers merchant, but he may have been pulling my leg.

Martyn.

Edited to whistlee's to prevent little  whistlie appearing.

Update, and a question to the plumbers out there - am I going to damage the boiler or myself, or more importantly Wifey, having had a 'fiddle'?

After 13 years of radiator TRV's whistling away when they start to close, I did some more googling, then some investigation. I've always assumed that there is too much pressure in the system. Not the pressure the combi is set at (though reducing the pressure down to about .7 bar helps a bit) but the pressure the water is being pumped around, forcing it to squeeze through the closing TRV. Extra bypasses, have helped, also almost closing off the on/off valve on the radiator, but doing the later makes the rad much less efficient.

So I had a good look at the pump yesterday and noticed that it had a black dial on a black background, with black 'power' symbols in raised plastic - so easy to spot!!!! Here's a photo, the flash helps a lot:



I then noticed that on the front of the pump is a power rating per setting, so I moved the dial from III to II which appears to reduce the pump from 95W down to 65W. The boiler got  a fair bit quieter, the whistling stopped, and this morning Wifey had a shower and the temp was ok (we struggle a little in the winter as our water temp drops so low you really can't keep your hands in it for long, so I have to dial up the water temp).

Appreciate as a complete ignoramous I shouldn't bguger about with a boiler, but absolutely nobody could solve this problem, and the whistling has steadily driven me insane!

Is this ok? Will there be any negatives I should look out for? Should I now put the pressure back up to a more normal 1.5(ish)bar?

Cheers.

Mart.
Logged

Just call me Mart.     Cardiff: 5.58kWp PV - (3.58kWp SE3500 + 2kWp SE2200 WNW)
desperate
Hero Member
*****
Offline Offline

Posts: 3542


Backache stuff!!


WWW
« Reply #13 on: February 07, 2013, 10:05:09 PM »

Hallo Mart, just spotted your question.
I would be a bit carefull changing the pump setting on your combi, I presume at that age it is a CDi boiler with the plate heat exchanger bolted straight on the diverter valve. When you demand hot water only, the pump circulates water round the primary gas/water exchanger  and the water/water PHE, most if not all those boilers do have modulating burners, but I think the flow rate may be quite critical to prevent the primary heat exchanger cooking itself, particularly in the summer when the incoming mains will be quite a lot warmer than at present. If you find the boiler "locking out" I would reset to the original position. Give me a couple of minutes, I have a download of the boiler structions for the CDi somewhere here, I'll have a peep.

spree Date

PS  it does indeed say in the manual to make sure that the pump speed is set to maximum.

I have also found that the fold down electrical enclosure is in the way big time if you need to do any work on the hydraulic components, and the stupid piddly little plastic hinges fall apart if you so much as look at them a bit sideways, then the whole enclosure drops and hangs on the wires facepalm facepalm not good.
« Last Edit: February 07, 2013, 10:14:18 PM by desperate » Logged

www.jandhbuilders.co.uk

still a crazy old duffer!
M
Hero Member
*****
Offline Offline

Posts: 5394



« Reply #14 on: February 08, 2013, 07:27:08 AM »

Thanks Desp, I was concerned about 'playing around with it'. So far I'm pretty sure the living room takes slightly longer to heat up, but still fast, and the shower seems ok, but we do have exceptionally cold water after 2 days or so of zero temps outside.

I will heed your comments about the water temp in summer, could I change the pump speed back to 3 (III) when the heating is off as the boiler has served us very well, but that whistlie is astonishing. It was much worse originally, but the installer connected up two sets of tails (one for the conservatory, and one for the loft) into bypasses, and that helped a fair bit. No longer plan to heat conservatory (have seen sense), and loft will need minimum heating if we ever bother - probably just use a TRV as and when (or if) needed.

Actually just had a thought - we have a 28CDi running 9 rads (3 bed semi) with 2 of those rads in the living room. We actually went for a larger boiler than really needed for expansion into the conservatory and the loft. Could this be a factor, in that the boiler is capable of pushing more water, greater distances than we have ever asked it to, hence it's a little 'overpowered'?

The boiler is in an upstairs bedroom, and the loft rad if/when we re-decorate it will be about 1.5m above boiler, probably something like a 600 to 800mm double.

Seems to be working so far, but as you warn, I don't want to cause damage down the line. Also thinking about replacing it for a more modern / efficient model, but it's pretty reliable and our gas consumption is only about 400pa (insulate, insulate, insulate!!!!) so watching and waiting.

Mart.
Logged

Just call me Mart.     Cardiff: 5.58kWp PV - (3.58kWp SE3500 + 2kWp SE2200 WNW)
Pages: [1] 2   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.20 | SMF © 2013, Simple Machines
SMFAds for Free Forums
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!