T/he header tank is quite clean to be fair and they have fitted a Bosch magnetic filter for the reason you stated.
So maybe just the lack of TRV's/ leaking valves, and the fact that it is not working.
T/he header tank is quite clean to be fair and they have fitted a Bosch magnetic filter for the reason you stated.
The process is quick, easy and fairly informal.
I would suggest that for many people that couldn't be further from the truth..when did you last apply for a court judgement?
20 years ago when I issued my 1st claim it was far more straightforward but the process is now more time critical and formal.
Right.... now I`ve been here before so I`m not going to count my chickens but... I turned the pump down to one and all the whooshing noises have stopped and I`ve been able to turn ALL the rads on, all hot, all quiet (previously I could only open 3 before the noises and vibration set in.) As I say, the morning will be the test but as it stands, what can I say, this seems to have solved it. Again, what, in laymans terms, has happened?Is the pump running?, if so what are those colours. Grundfos frequently recommend running at full speed, initially, constant curve III below, one green LED followed by two amber, this allegedly gets rid of the air eventually (I have my doubts about this) but it can create havoc with a OV system like yours if it is or has been left running at this speed as it will pump at a head of 6.4M which can cause pump over into the feed & expansion cistern leading to constant air ingress, if it is running in this mode&setting I would suggest changing it to constant curve I, just one solid green LED, which should still give a more than adequate head of 4.2M and far less chance of pump over, just press the setting button briefly to change settings.
This "valve" you show is probably a manual air vent, if there is a square on the top, a rad bleed/vent key should fit it, ensure you vent this often/repeatedly until all air is gone.
THe section of pipe where the cold feed is teed in frequently gets blocked/partially blocked leading to all sorts of problems, carry over etc and sometimes requires cutting out and replaced with a new section of piping, you could also convert it, like my 53 year old system, to a combined vent&cold feed with a almost 100% guarantee of no pump over.
Can you also follow the pipe back from the pump bottom (inlet), you might see a 15mm pipe with a 22mm pipe a bit further back but no more than 150mm/6ins from it, the 15mm pipe will be the cold feed from the feed&expansion cistern and the 22mm will be the vent that should carry on up and over the cistern and then turn back down with its end pointing into the cistern.
If you wish you can initially run the pump on speed III and look or get someone to look into the cistern and watch for any pump over through that vent on pump start up and again on pump shut down, then change to Speed I and look again in the cistern
View attachment 390741
Returning, if I may, to the problem of your heating malfunction (as I expect that nursing the good lady back to health has a higher priority than taking on the injustice system).This "valve" you show is probably a manual air vent, if there is a square on the top, a rad bleed/vent key should fit it, ensure you vent this often/repeatedly until all air is gone.
The section of pipe where the cold feed is teed in frequently gets blocked/partially blocked leading to all sorts of problems...
Can you also follow the pipe back from the pump bottom (inlet), you might see a 15mm pipe with a 22mm pipe a bit further back but no more than 150mm/6ins from it, the 15mm pipe will be the cold feed from the feed&expansion cistern and the 22mm will be the vent that should carry on up and over the cistern and then turn back down with its end pointing into the cistern.
Again, what, in laymans terms, has happened?

Well done Steve.THANK YOU TO EVERYONE WHO HAS CONTRIBUTED IDEAS TODAY, I APPRECIATE ALL YOUR TIME AND i WILL CONSIDER ALL YOUR THOUGHTS OVER NEXT COUPLE OF DAYS - ALTHOUGH HOPEFULLY, FINGERS CROSSED, WE HAVE A SOLUTION.
THANKS AGAIN!
STEVE
Yep, I will do that, but it is virtually silent now. Previously at switch on it sounded like there was a babbling brook flowing through the kitchen radiatorWell done Steve.
There may be air still in the system. Every now and then, go round and bleed the radiators and the air nipples in your airing cupboards.
Do be patient and only open the nipples so that you hear air. Not too much!!!
And make sure the heating is off and the pump isn't running when you do this.
Once again, THANK YOU to everyone who offered their advice, esp. johntheo5, I really can`t express what a relief it is to be able to finally put this behind me.
I`ll be honest, I want nothing further to do with them. Absolutely nothing. I didn`t pay for 3of the 4 visits, but absurdly they are still after £100 for coming outon the 3rd:
This morning, for the first time since June, the heating came on, silently, and all the radiators are hot. It seems the problem IS finally solved! (Sadly it`s so hot I can`t actually revel in my new-found warmth, but the time will come)
Yep, I will do that, but it is virtually silent now. Previously at switch on it sounded like there was a babbling brook flowing through the kitchen radiator
I`ve been round the radiators and there`s no trace of air, will keep an eye on everything as you suggest but it all seeems to be running as it used to. (I did get them to add inhibitor after they last flushed it)
Once again, THANK YOU to everyone who offered their advice, esp. johntheo5, I really can`t express what a relief it is to be able to finally put this behind me.
Glad you're satisfied.Glad you're sorted more or less now, there's another item that you might have a look at.
All gas boilers have a ABV (automatic bypass valve), its internal if the boiler is a system one but external if, like yours, a heat only boiler with a externally mounted pump, its purpose is to circulate water around the boiler and through the heat exchanger for a few minutes to cool/prevent it from overheating after the zone valve(s) close and the burner shuts down. It should look something like the one at the top of the photo and will have a numbered index which represents the pressure that it opens at, the idea is that it will partially open when the pump pressure rises slightly after the zone valves close, check its setting, if its set to < 0.35/0.4, check the pipework at either side, it should be cool, then with all rad valves open and the boiler firing, keep turning the setting knob very slowly clockwise until you just feel the pipe getting hot, stop then and maybe just turn it back anticlockwise say a 1/16th of a turn or so.
Ignore the txt in the attachment, I wrote that when assisting someone with a ABV problem
Was the UPS3 a new pump that was installed by these people.?
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