Central Heating Prob

philnicandamy

Anybody any clue about Gledhill Boilermate Gas heating systems?
this system was in a new property we moved to back in Aug last year & we've had problem after problem after problem

the latest prob is we've had no heating on the last few weeks due to the good weather BUT despite the boiler heating hot water which we have NO control over (its a thermal store) (seems to fire every 40mins or so) heat is pouring from the rads as well....each rad has a therm control which we've shut off yet still the heat comes.....we've had various engineers come to inspect the system yet nobody can see a reason as why?

my biggest worry though....we've worked out this is costing around £15 a week or so in gas (not counting any heating we would use)

has anyone got any clues?

Many thanks

Phil

Premier_2

Yes I know this system well.

You are correct - you cannot, or rather should not, stop the water from being maintained at optimum temperature in the tank as it relies on a thermal store.

If no hot water is being used (and no heating is on) them the boiler shouldn't be firing up every 40 mins - about once every 2-3 hours would be more reasonable.

Obviously as soon as you draw hot water, this will have a cooling effect on the thermal store and the boiler will then fire up to maintain the optimum temperature.

You say you've turned the heating off? This is controllable with the Gledhill programmer (usually a Grasslin device). With the heating off, the pump that pumps the water around the radiators should never operate.
(Note there is a separate pump to pump the water to/from the boiler)
Without that pump operating, the radiators should not be hot.

What's more, if the radiators are individually turned off as you describe, then the radiators cannot give out any heat unless the radiator valves are all faulty. The radiator valves cut of the water supply to the radiator if operating correctly.

Do you also have a room stat somewhere? If so try turning this down to minimum too. It won't cure the actual fault, but may stop the radiators heating up.

I do know from experience that there are many so called plumbers/heating engineers who have never seen and do not understand the Gledhill Boilermate at all - but won't say so, preferring to give out duff information.

All I can suggest is you try to find one that does understand the system and will quickly identify & hopefully rectify your problems. Unfortunately, I think Gledhill stopped trading end of last year so you can't contact them for further help.

In the meantime, if you are concerned by the amount of gas you are using, it should be possible to stop the boiler firing at all by turning off the Gledhill at the electrical isolation switch ... but that means you'll have no domestic hot water.
You could manually turn the power on for say an hour per day to heat up the tank - that should be sufficient to provide hot water for the rest of the day (obviously depending on how much you use)

Canucklehead

Good evening: A RGI in Reading is a Gledhill specialist and runs this website as well as a Gledhill forum.

HTH

Canucklehead

philnicandamy

Thanks for all your help.......Premier no room stat i'm afraid (heating off at controller/timer on boilermate)...to be honest we dont even now use a great deal of hot water either...we did have a shower that took feed from both cold & hot...but this since has been replaced with an electric shower after the central heating let us down various times with no hot water....although know what you mean though about duff info..the housing association this place belongs to apparently now have a boilermate "expert"....he came last week & shook his head saying "oh god not another one of these" & basically he didnt know why the boiler was firing every 40mins or so

Canucklehead....thank you for the info i'll post on the gledhill forum & see if I can contact someone

onething for sure....this is a very very weird problem!

Premier_2

I'm confused.

Do you think the boiler is firing up because of the heat being given out from the radiators?
Does the boilermate have the two pumps as I described?
Does the pump to the radiators start perhaps 30 seconds to 1 minute before the boiler fires up?

What is the other pump doing? i.e. the one that runs to the boiler. Is that running continuously? Or just when the boiler fires up and then shuts off a few minutes after the boiler goes out (this is how it should operate.)

Is there a small light you can see at the bottom of the boilermate? If so what is this doing? Does it remain on continuously?

I'm wondering if the boiler is firing up so often because the thermostat in the boilermate has failed (simple job to replace - they only cost about a tenner)
But this wouldn't explain why the radiators are getting hot.

What I also don't understand is that if the system is running correctly, the radiators will heat up extremely quickly compared to a traditional heating system - typically in about 1 minute or less because the already hot water in the thermal store is dumped straight to radiators. The radiators should be very hot to touch - not just warm. Your house must be like a sauna this time of year with the radiators continually hot.



Edit: The other thing to possibly check is the controls on the gas boiler. Is there some kind of adjustable/thermostatic controller on the boiler? If so, this should be set to maximum allowing the boilermate to be in control of when heat is required. If this isn't set to maximum, that could be why the boiler is firing up so often (but again doesn't explain the radiators heating up)

philnicandamy

Premier....many many thanks again for the help

we've written to the housing association & suprisingly they sent a surveyor yest to look at the system...turns out the radiators are in need of repair & the main control board on the boilermate is showing a fault

they've decided because parts are difficult to source (in particluar the main control board) they are coming tues next week to rip the system out totally & installing a combi system thank god!

Thanks again for all your assistance really really appreciated you taking the time

Phil