Central heating query

[bobsnail]

ok firstly i know this is a common problem and i have searched the net and these forums but im still unsure...

Basically when i turn on the hot water my radiators heat too (even with the thermostat on minimum). turning on the radiators DOES NOT seem to heat the water though (water was luke warm only when i tried today).

afraid i don't even know what type of boiler (conventional i think, as its not combi and too old for anything else)i have but its about 25 years old.

Potterton boiler
New horstmann centaurplus c27 controller.
New Horstmann HRT2 thermostat

Horstomann stuff installed by plumpers (to their mind correctly). I since had a dispute with these guys so cant ask them back.

In the loft i have a Sunvic SD2701 Sprint return Actuator... Its a 3 way jobbo..

sooo Im thinking one of 3 things :-

a) Sunvic SD2701 possibly duff from internet research etc.

b) Controller connected incorrectly (perhaps unlikely as it seems to work)

c) The previous owner said something about a lever he got a central heating 'expert' to install in the airing cupboard to allow manual switching between rads and water. Interestingly the pipe he pointed too had a gas lever on it?? the plumbers (that i fell out with due to lack of professionalism) did establish that the reason the radiators weren't working was because of that gas lever and turned it (it is a water pipe).. Radiators now work but come on with hot water too..

Can anyone conclude what the issue might be from the above info? I appreciate that it might be hard without seeing the system, but id like to have some idea before calling in the pros.. since my last call to plumbers was expensive and unpleasant

 

[outinthestix]

To check the sunvic, switch on hw only and feel the pipe coming out of the valve which goes to the rads. If it warms up it is faulty and needs replacing. Otherwise it could be an installation fault with the pipework.

 

[bobsnail]

doh....cant believe i didnt think of that..will give that a try when next out there. Im hoping it is the sunvic to be honest.. reckon i can swap that out myself

Is all of the mechanism that switches between HW and CH contained in the sunvic? I mean does the T pipe that the sunvic plugs into contain a valve that could have gone, and is that likely to need replacing too.

Sorry for the noob questions.. First time buyer and not had to do stuff like this before.

Many thanks for your reply

 

[westeleven]

seems to me that it might be a pipework problem that the previous owner knew all about and decided to have that 'lever' installed as a quick fix. If it works that way then why not just make do with having to do a manual control of the CH until such time as you decide to redo your whole system? the problem will go away soon when our summer arrives . good luck.

 

[bobsnail]

'Making do' may well be my only option... Being a first time buyer money is kinda tight and i already replaced the control systems, kitchen and bathroom, got every room replastered (previous owner used rubberised paint!!!).

Thing is i might have to 'make do' for some considerable time so if its a relatively cheap and easy fix id like to sort it. Not least becuase the lever i mentioned doesnt seem to turn (not easily anyway)

Also the rads seem to get much hotter when the hot water is on... can a radiator get too hot i wonder..

But i agree. a new system is required... i just wont be able to afford it for a few years...