central heating problems

[tombolton82]

hi,
our central heating system is not working properly. we have a gravity fed system which has a switchmaster 805 timer which is really loud and the buttons dont work properly and a switchmaster valve (i think its tha three port valve which feed the water to the hot water or the central heating) which is also not working.
i think both need replacing, do i need to get like for like replacements or will different timers be compatible??
also i need to change the thermostat which is made by satchwell, for a new digital one. would that be just a straight forward swap or is it more complicated than that??
i've found this in screwfix http://www.screwfix.com/prods/94777...ls/Hortsmann-312B-Heating-Control-Master-Pack would it be any good?
any suggestions or recommendations would be greatly appreciated.
cheers guys
tom

 

[kevplumb]

i've found this in screwfix http://www.screwfix.com/prods/94777...ls/Hortsmann-312B-Heating-Control-Master-Pack would it be any good?
any suggestions or recommendations would be greatly appreciated.

you might have to change the nuts on the 3 port valve (no big deal)

and you may have a spot of wiring to do

but on the whole

go for it

 

[JayJay1978]

Don't buy Horstmann, they are unreliable junk, stick to Danfoss, Drayton or Honeywell.

 

[Boilerman2]

Ditto Horstman are rubbish!! honeywell do a Contractor pack which will have everything you need and its quality kit as well

 

[tombolton82]

I did buy the cheap crappy hosrtman in the end. I'm not going to be here long so didn't worry to much but thanks for the advice.
I've been putting it in this afternoon and I've got a bit stuck already, the timer went in easily enough the wiring was all the same. The hit I'm stuck on is the 3 port valve, the old one has more wires and they are all connected to something?? It has a blue, red, orange, White, yellow, and earth. The new one only has 5 which are blue, grey, orange, White and earth?!? Wdo I need a different valve or is there a way around it?
Cheers
Tom

 

[seco services]

sm---------new valve
earth------earth
neutral----neutral
yellow-----white
white------grey
red, join to orange----orange

 

[tombolton82]

Thanks for that. I'm a bit confussed about one bit though. What do you mean by join the red to the orange? On the old sm they are not joined so do I put the new valves orange wire where the old orange is (which goes into a junction box with a blue wire) or into where the old red is which joins a red at the junction box?

 

[tombolton82]

Sorry the oldred joins a brown wire then goes into the box with a red on the other side and the orange joins a blue with nothing on the other side of the junction box

 

[seco services]

the red, orange went to seperate terminals.
take the red,orange out then put a link wire linking them together.
then put orange in one of the terminals as the two are now linked.


sm red would be sw/l to boiler.
sm orange would be hw on from cylinder stat.

 

[tombolton82]

Ahhh I see, thanks for al your help