Just as an update. Those who thought it was the diverter valve or venturi, WRONG!
It was simply the opentherm ESI ESRTP4RF+ that was the problem.
Apparently these controllers are nothing but problems. He fitted a wireless room thermostat instead of an opentherm one, and it has worked...
Thanks for the response. No apology needed.
I asked him that just now. He said that otherwise you fill the ''syphon trap bottle'' with all the debris, which then takes quite a while to flush out. Which makes some sense to me, but I also get why you could do it in situ. But he also said it is...
@kidgreen61. Wow. That was a bit harsh!
I was chatting with the guy and we were drinking tea as he worked. I have never seen a more professional and decent plumber. He explained what he would be doing, started draining the system down, was concerned not to make a mess or get the laminate floor...
Thanks Gas112 for replying. A lot! It was a close call between that and a brand new boiler. To be honest, he did say it didn't really need a new burner but that the original one was looking tired and as he had the old unit off and a brand new seled box in the van, it was not much on its own -...
Thanks Cross Thread - exactly what I thought as it only happens when heating is called. A bit annoying as I saw the guy service the divertor valve as mentioned, otherwise I would not have believed it was done. He fitted a brand new 'service kit' which he even showed me. It had the two end nuts...
Hello guys. I have an Ideal Combi 30 boiler. It makes an odd noise and I would love someone to say what it is.
This ONLY happens on heating, never on hot water. WIthin a few seconds of heating been called, the boiler makes a deep, booming vibration a bit like a low didgeridoo being played. If...