Radiator banging / clicking - possible reaction to F1 protector?

[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.