Central heating electrics

[benjawan]

Hi I have just joined this.
Can anybody help please I have had 3 electricians try to fix this problem and so far they have failed and I dont understand why.
When the central heatin is off and the water is on the radiators still come on and do not respond to the thermostat.

We have a system system
gas boiler
programmer
2 motorised valves
1 pump
wirless stat ( recently installed )
wireless reciever
water stat
This is driving me crazy the ist electrician installed the wireless stat before that we did not have this problem I have had him back 3 times and he still cant find out why this problem is. I have checked the times on the main contoller and that the wirless stat and reciever are talking to each other.
Can anybody please

 

[ericmark]

There are many central heating systems. Often there are levers to allow bleeding in motorised valves one could be latched which can cause this problem even when there is nothing electrical wrong.

 

[benjawan]

thanks eric where would i find one of these levers

 

[ericmark]

they are between the electric and water bit. Often the valves have micro switches which also control the system. So valve also acts as a relay. It is sometimes latched on as a quick fix when micro switches or other parts fail.

I came across it with Y plan using single 3 port valve. Not sure which plan you would be using. Which is why only really stab in dark.

 

[ericmark]

When trying to help someone before I made this web page it may help.

Links to Honeywell no longer work now you need to log in but anyone can register to down load the plans.

 

[benjawan]

hi
we have 2 motorised valves on 28 mm which are 2 way

 

[benjawan]

Thanks for the web page I will study it.

 

[benjawan]

there is nothing between those points only motorised valves 1 for the water 1 for the heating

 

[ColJack]

stupid suggestion... 1
ask the neighbours ( 2 each side at least ) if they have a wireless stat... might be cross talk between them?

my dad had a similar problem with a doorbell.. next door bought one and his rang when someone pressed their bell-push..

stupid suggestion... 2
put the wired stat back on for a few days and see if it stops playing up.. that way you know it's the new wireless stat or it's location

stupid suggestion... 3
the stat may have a "frost protection" or "comfort" setting that is set to a high default?

 

[Lectrician]

Very often when this happens it is not due to an electrical problem. The system could be wired correctly, and there could be no fault at all.

I have seen some systems plumbed incorrectly. If the returns from the radiators are not marshalled together, or not behind the return from the cylinder, you can get some 'backflow' through the rads. It is difficult to explain, a drawing would help.

If the electricians cannot find a fault, perhaps try a plumber.

 

[ColJack]

given that the system worked fine before the new stat was put in, then it's a fairly safe bet that it, or it's installation are to blame..

 

[Lectrician]

GOOD!

Untitled

• Lectrician
• 11 Jun 2009
• 1

______________________________________________



BAD!

Untitled

• Lectrician
• 11 Jun 2009
• 1

 

[Lectrician]

given that the system worked fine before the new stat was put in, then it's a fairly safe bet that it, or it's installation are to blame..

Oh, I missed that.

 

[ccrowe]

I had exactly this problem a few months ago. The trouble was that it was an intermittent fault so whenever I turned up the system worked. When I was somewhere else, the system failed.

I eventually traced the problem to a faulty valve. Replaced the actuator and all is now ok.

S Plan system if that helps.

 

[D_Hailsham]

If you have two motorized valves, you probably have a S Plan System.

This is the basic layout and wiring diagram, though yours will be slightly different as you are using a wireless stat.

View media item 71 View media item 72