Baxi Bermuda Back Boiler Being Bonkers. Possibly.

[sambotc]

It cycles on and off as the water temperature drops below the boiler thermostat temp within the heat exchanger/pipework. Boiler then fire's to satisfy thermostat again for a couple of minute's until stat is satisfied then the whole process repeats itself again and again.

You could turn the boiler stat down which will reduce the water temp but also the radiator surface temperature, it won't stop the cycling though.

Sam

 

[nogoodatfaultfinding]

Right im not having a dig but have you honestly not seen a Classic, a 240 a Solo in the last 20 years, cmon you must have seen a boiler with apilot in that time!
Ive only been doing it 10 years and 75% + of boilers i come accross are pilots

I don't do this commercially! I've installed a couple of central heating systems, but they have been in my own home (more than one house!). Other than that, I've only ever worked with non-pilot-light boilers (eg when a friend/relative has asked me to "have a look" at their boiler)

I genuinely had no idea so many homes still had pilot lights merrily wasting gas all hours of the day and night!

Anyway... I can see the issue with the HW always working with the CH, but that still doesn't explain why when the CH has achieved temperature (room stat has turned off) the boiler still fires up once every 5 minutes for about 15-20 seconds, running the hot water circuit. It's definitely the HW circuit, as if the CH is turned completely off (programmer off) the boiler still does this. The water in the cylinder is absurdley hot (I'd guess well over 80deg) and desperately needs turning down, which is a bit difficult with no cylinder stat. I'd also much rather the boiler did NOT try to keep the HW tank up to temperature all the time, but if it has to run the HW all the time the CH is on, then so be it (and what an irritating and wasteful design that is!)

First off can i appologise for coming accross as rude (If I did) as that was not my intention.
I assumed (and we know what that does) that you were just a general RGI going from job to job.
There is no way to stop the boiler cycle as this is what it is designed to do within the system you are looking at and as stated you could fit a Cylinder Stat or a C Plan but its probably more hassle than its worth.
As someone kindly posted you could turn the Boiler Stat down (should really only be at 3 quater anyway) however it will then just cycle to this temp instead of the higher one.

Once again sorry for my assumption.

Charles

 

[DavidB5]

No worries! It's very difficult on forums to judge a noob person turning up, as they could be anyone from mr-know-it-all to mr-knows-nothing. I've done exactly the same on other forums I frequent when someone turns up and says something a bit odd!

As I said, I'm not doing this commercially so have very little experience of different boiler models and how they are designed to operate. I understand the theory just fine, but I'm looking to make use of other people's experience in how certain models actually function.

Just as a sidenote, although I'm not an RGI, I'm a mechanical engineer and I do work with Gas a lot, (all out-of-scope work) and have taken training schemes that allow me to work with gas at up to 250BAR. I've also done some very "interesting" modifications to some boilers to make them do what we need them to, most of which would make an RGI panic and run away!

Getting back to this poxy bermuda... whereabouts is the boiler stat on it? The hot water temperature is way way too hot, and the radiator surface temperature is remarkably high, so I suspect it's wound up to 11. Also, does that really mean that the ONLY temperature control of the hot water cylinder is done through the boiler stat? Strikes me as crude at best.