Radiator banging / clicking - possible reaction to F1 protector?

[TheGiantHogweed]

Hi.

We’ve had rather a lot of noise issues with our radiators since we had a new boiler installed. Our radiators other than 2 more recent ones are all over 30 years old.

When the boiler got installed in the middle of 2020, after the first few days, we had several loud airlocks each day. Probably up to 10 times in total until we got the plumbers round to sort it out. I can’t remember exactly what they did, but the air locks stopped occurring then. But what then was the case was that whenever the heating was on, the main radiator that must remain on all the time seemed to have a sound similar to a cold tap permanently running. That sound was amplified to the room above, unless the TRV on this radiator was either on 5 or totally off.

We got the plumbers back, and they then drained the system (not a blast out though) and added some Fernox F1 Protector.

This seemed to remove the issue I described with the sound like a tap was running, but introduced a whole load more.

The system clicks and bangs occur very regularly when the heating is on. It however is much more noticeable in my bedroom, but the noise is very similar in many other places in the house. It is not coming from the radiators, but they are what makes it more audible as upstairs all the pipes are under the floorboards. The F1 Protector I’m guessing caused some sort of chemical reaction. Every single day, loads of air / gas was generated and the radiators could be bled very frequently with more build up of whatever this was. The water was also very dark grey and smelt strong. We kept dealing with this throughout the winter ourselves and although the noise remained, the issue with the gas does seem to have gone now, probably because the radiators hadn’t been used this last summer.


Now, the clicking decreases when the heating is off at the boiler, but it still clicks or bangs randomly usually at least once an hour through the night. Sometimes it can be incredibly loud.



From what I’ve read, this now could be many things:


Boiler kettling – It seemed that F1 protector it supposed to help with this, but it seemed putting that in caused trapped air and other nasty reactions.

Expanding / shrinking pipes – This sounds like it could indeed be the case. As I can lift and move my radiator slightly and feel it rubbing in the hole in the floorboards, and I can almost create the identical sounds myself by doing this. However, the radiators and pipes have not changed since our boiler got replaced, so as that is the case, I can’t understand why this should be related. Our heating with our old boiler just bade a very quiet and consistent tinkling while on, and no noise when off.

Dirty pipes – While we had the F1 protector put in supposedly to clean the system, given the reaction it caused, it probably has made it worse. We don’t have air / gas in the system now and the water seems clean, but I obviously can’t tell what the pipes are like. I don’t believe it is related to the radiators now, as I can turn them off at both the TRV and other valve and the noise still occurs from the pipes.


As it is a new boiler with very old pipes and radiators, it is hard to know if a full system flush will solve this issue. I know that these radiators and pipes can be quiet, and nothing physically should have changed about them. Just likely to be something in them.



This clicking / banging has been irritating me so much that I’ve done rather a lot of recordings of it. So I can explain what it is better.



This first link below is actually from last year. This was during the day when I was at my desk. The microphone easily picks up me pressing a few buttons on my keyboard, but then it just sounds like a hard metal object hits the radiator hard. The radiator is nowhere close to my microphone, which just shows how loud it can be. This is a good example of what can occur in the night.

http://www.wetherby.me/wiki/pub/Sandbox/RandomImages/1_Radiator_Sound.mp3

This next clip is close up to the pipe when there was an obvious reaction of some sort. You can hear what sound like fragments rolling around in the pipes, spitting, gurgling and then this clicking and banging begins. The gurgling has long since stopped, but the banging and clicking remains.

http://www.wetherby.me/wiki/pub/Sandbox/RandomImages/11_Radiator_Sound_Close_Up.mp3

Number 6 was only from a few days ago when the boiler was on, but my radiator off. I’ve edited the recording and joined many of the sounds closer together. They sound similar, but can vary a lot regarding how far apart they are.

http://www.wetherby.me/wiki/pub/Sandbox/RandomImages/06-Left_Pipe_-_Morning_Noise.mp3

This is an awful lot of information, but I’m really stuck with what this is most likely to be, and what sort of people would know most about it and be able to sort it.







Many thanks.

 

[TheGiantHogweed]

I'll check the pipes above the boiler tonight right when the heating first comes on, if I get the chance.

When our new boiler got installed, they set it to 69 degrees claiming that was the most efficient. But we had read that this can cause noisier heating and possibly the reaction we had with the build up of gas (hydrogen?). However, since then, we turned it back to 62 or 63. Can't remember at the moment, but it was one of these two, and this was what we had our old boiler at too.

This is the pressure gauge. It looks to be just under 1.0. When I took this picture, it was the middle of the day, over 3 hours after the heating had gone off. Just like the night, there are still occasional clicks or louder bangs, but usually only a few an hour or even less. But that is a real issue at night as it is louder than anything else by a huge margin. And as I said, this does just seem to be in the pipes rather than the radiators, but the radiators are where you hear the noise more as upstairs, all the pipes are in the floorboards.

After I have checked the pipes above the boiler this evening, I will let you know and then see if I can try the alternative pump options. Though I myself still struggle to see how the pump that doesn't operate when the heating is off can be related to the bangs when the heating is off. Will see though.

 

[John.g]

If the E.vessel is effectively connected into the discharge side of the pump rather than the suction side then when running at the 6M head originally or even the 5M head now then there was/is a very good chance that the system is running under negative pressure in some parts so at least until the E.vessel piping position can be established I would recommend increasing that cold pressure (via the flexible top up hose) from just less than the present 1bar to say 1.3ish max 1.5 as you don't want to exceed ~ 2.3/2.5 bar with a hot system, then regularly vent the system with boiler off and maintain this pressure.
Flow temp anywhere < 65C should be fine IMO.

Banging is strange alright as it apparently only appeared on boiler changeout so difficult to understand why this is, also as it happens hours after normal cool down with pump off, also just ensure that the pump does in fact shut down and isn't running continuously.

All you can do is to address the obvious and the answer to the riddle might manifest itself.

 

[TheGiantHogweed]

If the E.vessel is effectively connected into the discharge side of the pump rather than the suction side then when running at the 6M head originally or even the 5M head now then there was/is a very good chance that the system is running under negative pressure in some parts so at least until the E.vessel piping position can be established I would recommend increasing that cold pressure (via the flexible top up hose) from just less than the present 1bar to say 1.3ish max 1.5 as you don't want to exceed ~ 2.3/2.5 bar with a hot system, then regularly vent the system with boiler off and maintain this pressure.
Flow temp anywhere < 65C should be fine IMO.

Banging is strange alright as it apparently only appeared on boiler changeout so difficult to understand why this is, also as it happens hours after normal cool down with pump off, also just ensure that the pump does in fact shut down and isn't running continuously.

All you can do is to address the obvious and the answer to the riddle might manifest itself.

The first part I have put in bold, I may just need describing what the two heads are.

It is true that we didn't have this banging or clicking at this volume with the old boiler. It used to just be a very quiet and consistent tinkling sound. However, this banging didn't start until after the 2nd time the radiators had been drained and refilled. And on the 2nd refill was when we had f1 protector added, which was when we had this reaction that triggered the build up of gas or air almost every day for most of last winter.

The clicking and banging is much more frequent when the heating is on - sometimes can do it many times per minute for quite some time. But usually, when it does it in the night, it is generally predictable that the clicks or bangs that you hear will be the louder sort. Almost as if something has been building up and it then releases. Hard to describe. It is a loud enough bang to cause vibration, as I was irritated enough that I tried to guess when it would happen, and I held the pipe under my TRV one time as it did it, and you can certainly feel the vibration from the bang.

As none of the pipework under the floorboards has been modified or moved in the slightest, it is hard to understand how the cause of this banging would be related to the pipes moving well after the heating has gone off. Unless it is something to do with the fact the pump makes it cool down so much quicker, that the pipes possibly done contract at the same speed, and end up taking much longer. But I really don't know here.

 

[John.g]

The pump should stop after a few minutes at most after boiler shut down.

Full speed CCIII on the UPS3 is well over 6M and CCII is over 5M, the proposed CPI is a 3M constant head which should do the job pretty well IMO.

 

[TheGiantHogweed]

I appreciate your help, I just am limited as to what I can understand as the graph doesn't mean much to me unfortunately. It is the meaning of the 6m, 5m and 3m that I don't know about.

I'm a slow learner so I may take a while to understand!

 

[Deleted member 123817]

The higher the pressure (head) the greater the circulation flow, some systems depending on number of rads length and diameter of pipework etc will require higher pump heads than others, that's why you have multiple choices of pump heads. Pump head (differential pressure) is normally expressed in meters M, M/10 = bar so 6m=0.6bar, 5M=0.5bar, etc,

 

[TheGiantHogweed]

Thanks, this hopefully will make more sense to me eventually.

We have 7 radiators. 5 being pretty large and the bathroom and my bedroom (both small rooms) have smaller ones. The hallway is the only one without a TRV as that is the main one (not sure the name for it).

Two of our radiators are newer than the others, but still over 15 years old rather than well over 30, but the pipework could well be a similar age to the house which was built in the 60s.

One example of the sounds in the night is below. I had my microphone recording it the whole night, and joined several of the sounds together. Typically, the really loud band was not there this time. The best example of what they can be like was in the first clip in my first post.

http://www.wetherby.me/wiki/pub/Sandbox/RandomImages/02-Right_Pipe_-_Night_Sounds.mp3

Our heating comes on soon, so I will make sure i check the pipes first, then let you know. They I will try changing some of the things you have suggested.

 

[TheGiantHogweed]

right, when the heating first came on, it was the pipe at the top right that first started to build up heat. After a few minutes, the other one got warm, but didn't seem to quickly get hot like the other. As the water was going along the pipes here, I could hear what sounded like fragments rolling around in the pipes above the boiler - a similar sound to what I had in my bedroom pipes a while ago.

Now the heating is on, despite my radiator being off off, the pipes are clicking and ticking away many times a minute, and while I know it can be normal for it to do this more quietly when the heating first comes on, it is the fact that it keeps stopping and starting these intervals of many clicks while the heating is still turned on.

I'm unsure on how to change the pressure gauge though.


By the way, I have also checked the pump. As is has an LED when it is on, I know that it must have been off when I last checked it later in the evening the other day when the heating was off, as the LED was off. It turns out it is on speed 1. My dad told me he had put it to 2, but it may be too long ago to remember exactly. Let me know what other mode to try now.


Thanks.

 

[John.g]

Open the black arrowed valve 90 deg anti clockwise and increase whatever pressure its showing now by 0.3 bar but no more, reclose valve.

Flow pipe on boiler seems correct.
Will revert later re pump.

 

[John.g]

To select CP1, press the setting button for 3 sec, then single presses until 1 flashing green at one end and 1 flashing yellow at the other, CP1 is now selected with a constant pump head of 3M.

 

[TheGiantHogweed]

Open the black arrowed valve 90 deg anti clockwise and increase whatever pressure its showing now by 0.3 bar but no more, reclose valve.

Flow pipe on boiler seems correct.
Will revert later re pump.

I've changed the pump mode / speed to CP1.

I just need to fully understand that valve does, and make sure that it isn't easily possible to go wrong in a way that matters in the long term. As usually, I don't do any of this stuff myself.

 

[John.g]

You cant go wrong, that valve allows mains water into the system/E.vessel and even if you forgot to close it the red topped safety (PRV) valve on the boiler top will open at 3 bar.
So just open it slowly, you should hear water passing through it and the pressure gauge should start rising slowly, reclose the valve when the pressure has increased by 0.3 bar.

 

[TheGiantHogweed]

Done that now. Got the valve to be showing a fraction over 1.2. Still hearing the clicking, but possibly should give it time and wait for the heating to go off and give it another cycle.

The last 2 things done by plumbers did make a significant change to the sound but not making it quieter!

I almost wish I had left it as it was (as in not have the plumbers drain it again) as although that was still annoying, it was nothing like as bad as this. Before the time they emptied it for the 2nd time, it sounded like a cold tap was running (not sure, but I notice virtually everywhere seems to have a louder cold tap than the hot one) You could only solve this by making sure all of the TRVs were on maximum, so it was an issure if you wanted good control of the temperature. But at least that was totally consistent and predictable, and only the case when the heating was on. This clicking and other stuff only seems to have been an issue since the system was last refilled with the f1 protector added (it didn't have a power flush at any point)

So if what you have suggested and I have now done doesn't work, I'm wondering if a power flush may be the next option, though it obviously will cost and we can't be sure it will work.

 

[John.g]

I wouldn't be holding my breath re the above steps.

Are you getting any air/gas when you vent now (cold).?.

There should really be a air vent right on top of the boiler or on the flow pipe as it leaves the boiler, the boiler probably has a internal one but this is generally shut off after commissioning.
I suppose any air should really gather somewhere else where you can vent it.

I honestly can't suggest any other options, a power flush may work as you say?.

The only thing that I am not 100% sure about is the boiler flow being on the right hand side, the eManual doesn't specifically say so but the schematics of different pipe layouts suggests that it is.
You might check that out with Ideal Logic or some installer here might inform.

Just one other thing, that pressure should rise and fall between a cold and hot system by maybe 0.5bar.

 

[TheGiantHogweed]

I wouldn't be holding my breath re the above steps.

Are you getting any air/gas when you vent now (cold).?.

There should really be a air vent right on top of the boiler or on the flow pipe as it leaves the boiler, the boiler probably has a internal one but this is generally shut off after commissioning.
I suppose any air should really gather somewhere else where you can vent it.

I honestly can't suggest any other options, a power flush may work as you say?.

The only thing that I am not 100% sure about is the boiler flow being on the right hand side, the eManual doesn't specifically say so but the schematics of different pipe layouts suggests that it is.
You might check that out with Ideal Logic or some installer here might inform.

At the stage we had large build ups of air or gas, it seemed that most days, virtually all the radiators in the house would get quite a lot of whatever this was in them. Some of them you could be bleeding for over 30 seconds with the water only spitting just slightly, with significantly more of whatever the air was. Presumably the reason why it was spitting liquid just slightly it was because there were a load of bubbles inside or something.

It is possible that what settled this was the summer and having no heating used at all for many months. This water was very mucky last winter when this reaction (to something) was occurring, so presumably although the water seems clean now and the air is gone, some of the muck build up must be somewhere and maybe it could be related to the noise continuing?

I've tried bleeding the radiators again and they all seem full up. Haven't noticed any air or gas in them since they have been off over summer.

 

[Ric2013]

I doubt the age of the radiators has ANY bearing to the noises. Until they leak radiators don't really change in behaviour. By age, I do literally mean any age. Two thirds of the radiators in the building where I am writing this from are 49 years old.

 

[TheGiantHogweed]

I doubt the age of the radiators has ANY bearing to the noises. Until they leak radiators don't really change in behaviour. By age, I do literally mean any age. Two thirds of the radiators in the building where I am writing this from are 49 years old.

We first thought that nothing should change with the radiators as the pipes hadn't been touched. But all the TRVs had been replaced as well as the boiler as it was that that had failed.

 

[ShaunCorbs]

Did they get cleaned eg with an ADEY magna cleanse ?

 

[TheGiantHogweed]

Hasn't been 24 hours yet, but not sure if that makes a difference. But after the adjustments made to the pump (Speed 1 to CP1) and the increase of the pressure gauge to 1.2, neither seem to have made a difference, but were worth trying. Still getting the same clicking and occasional loud bangs in the night when the heating is off.

Did they get cleaned eg with an ADEY magna cleanse ?

As I know we haven't had a power flush at any point, I presume that was never used. We just had our system drained when we had our new boiler fitted, then drained again when we complained about airlocks and noises like a tap was permanently running. They then drained the system and refilled the system with F1 protector in October a year ago. It was just after this when we started using the heating more often that we seemed to get this reaction that caused dirty water and gas / air build up as well as a load of clicking and banging.

Over the summer, the air has gone and the dirt also, unless it has settled somewhere, but nothing has been done since we had this issue. Now it is winter again, the noise has come back. It is just so hard to diagnose what it is.

 

[ShaunCorbs]

It could be something as simple as heat expansion due to the little plastic radiator clips breaking at the back where it goes onto the metal bracket