Retrofitting central heating with thermostats?

jdpl28

Hi,

I've got an old'ish central heating system that doesn't have things like outside thermostats, thermostats on the hot water tank & an isolation valve on the hot water system. I'm wondering could I install these things myself? I persume you'd need a new control unit along with the above. Would there be any dangers involved? for instance if both the isolation values were shut down on both the tank & rads? Is there any other things like this I'd need to make sure about?

thanks,
J

darcy.jonny

first give the name and model of the boiler ... yes in junction with a time clock there can be a thermostat wired to the boiler , its just a case of running cable to your sitting room anywhere else wouldnt be worth the effort

to put a thermostatic cylinder valve on , will require you to drain down partially the heating system .. dangers apart from flooding oviously , causing sedement to build up at lower levels of the system causing the circulation of the system to be badly affected as its an old system i gather

an isolation valve on the hot water system ,,,,, firstly the isolation valve is on the cold feed to the cylinder from the storage tank . (never ever put an isolation valve on the pipe coming from the top of the cylinder . EVER) the cylinder fills from the bottom thats what trow people off ....

to do this u need to isolate the mains supply and drain down the attic storage tank , fitting the valve wouldnt be to much of a problem just be careful not to reef out of the pipes as you could damage the storage tank and the cylinder .


of the three things you mentioned the last on the isolation valve on the cold supply to the hot water cylinder is a no brainer and go ahead and do it if your confident .

the second one will require some knowledge of heating systems , if things go wrong for you here it could be an expensive lesson requiring chemically cleaning the heating system . ... but again it would be worth doing if u have a bit of knowledge

the thermostat ............ if she is and old bolier ild worry about the condition of the pcd to be going and messing around with it . i personally wouldnt bother with it , if the system is correctly balsnced , cleaned etc. it wont a great benefit to have really , not on an old system .

crosstownk

darcy.jonny wrote: »

to put a thermostatic cylinder valve on , will require you to drain down partially the heating system ..

Not necessary - a 'strap on' type cylinder stat will do.

I think the OP means zone valves when he mentions isolation valves. I get the impression that the OPs system fires up and just runs based on the boiler stat setting rather than the room/DHW temperatures. If that is the case then he could be wasting a lot of fuel. A new control unit is not necessary - a simple timer will do but obviously a two channel timer would be preferable.

jdpl28

Hi, yea. thats what i ment. Current system is:

boiler: Potterton suprima - 2 years old
control unit - Sunvic Select XL - with 2 zones (hot water & rads)

currently theres only one zone shutoff valve - on the rads. What I was proposing to do was put a second one on the hot water system (oh, the bathroom rad is also fed from the hot water zone). I was also proposing to get a system that has an outside thermostat (for shutting off the rads when not below a certain outside temperature), also a strap on thermostat to the hot water cylinder & thermostat for the main living room.

For all this I guess I'd need a new controler unit? any suggestions on what one I should go for?

also, if I was just retrofitting a zone shutoff valve for the hot water system, what do I need to consider.

thanks!
J