central heating programmer broke i think

[poppy1]

Please bear with me - its my first post on my house and I'm not used to forums and no little about heating systems (i am a woman - is this an excuse)

I have gas central heating with a tank in the loft and a cylinder in the hot press and a boiler in the store downstairs. Hope that sorts out what type of system it is. The programmer is a sunvic select 207. It is about 10 years old i think. Till a few days ago it done what it is supposed to so, came on and off as set am and pm. Now it does not. It still works manually if i switch it on and off but the programmer/timed bit fails to work. When i switch it on/off manually the heating system/water works as it should. no other problems.

Am i correct that the programmer has given up the ghost? If so is all i have to do is buy a replacement and get someone to wire it in?

I noticed the the same model number is still on sale but looks different of course from my old one. Link to new one below.

http://www.discountedheating.co.uk/shop/acatalog/Sunvic_Select_207_XLS_2_Channel_Programmer.html

If as i think it is the problem do i just buy the above or should i leave the choice of purchase to the professional. Will the newer model work OK with my system (assumed it will the model number is the same as one on now)

Last question - who do i call to fit it - an electrician or plumber?

Thanks ever so much - im sure i have got it wrong but i have no one really to ask apart from calling a plumber. Just want a bit of direction or confirmation before i do that.

 

[TicklyT]

If your boiler is located in an external store room, in the present weather conditions the frost 'stat may be taking over control of the system instead of the programmer.

If the frost 'stat senses temperatures close to freezing it overrides both the programmer and room thermostat, and runs the boiler (often in the middle of the night, when temperatures are at their lowest) until the boiler is warm enough to stop it freezing.

A by-product of this 'unwanted' running of the system is the room 'stat may already be satisfied, and stops the boiler from firing when the timer does switch it on.

If this isn't what's happening, then it could be your programmer.

Most programmers just clip onto a fixed backplate, and can be removed without touching the wiring. If you are changing 'like for like', just release the screw at the bottom of the backplate, lift the old one off and hook the new one on.

If you are changing to another make or model of programmer the backplate may need replacing or re-wiring.

 

[poppy1]

thanks for your reply. what should I do first. call a plumber to see if the frost stat is the problem or buy and fit a programmer. I know its difficult to say but if you were me and couldnt determine the fault yourself what would you so first? It is in a store room at the back of house but a radiator is in there and operating. it is no colder in there than the rest of the house. would this lead you to thinking try new programmer first?

If it is a programmer is it an electrician i need if its not a simple like for like connect back to the back plate or a plumber - sorry if silly question - just want to get it right at the lowest cost to me as possible