Unless i am missing something ??? I don;t see how the boiler is being supplied with 2 live's ??? as I see it only the pump is being supplied by a live via 1) the switch live or 2) a permanant live ?? , the boiler would only have 3 wire's to it S.Live , Neutral & Earth ???? switch live to boiler would be off e.g on programmer ? time clock ???
Perm and switched live to new boiler?
- Thread starter pmx_super
- Start date
Sponsored Links
Er. you've confused me now.
Most modern mass market boilers need L, SL, PL, N and Earth.
As discussed, many old perm pilot models just have SL, N and Earth provided from the airing cupboard or wiring centre.
This leaves a typical heat only condensing replacement short of 2 vital connections.
However some boilers ie; Viessmann Compact can get by with L, SL, N and Earth
Very few Band A/B boilers can do with just SL, N, Earth.
If the programmer or power supply for the entire CH system is nearby, the L is covered, so a Viessmann Compact or the Baxi mentioned earlier will work, needing just the supplied SL, N and earth.
Most modern mass market boilers need L, SL, PL, N and Earth.
As discussed, many old perm pilot models just have SL, N and Earth provided from the airing cupboard or wiring centre.
This leaves a typical heat only condensing replacement short of 2 vital connections.
However some boilers ie; Viessmann Compact can get by with L, SL, N and Earth
Very few Band A/B boilers can do with just SL, N, Earth.
If the programmer or power supply for the entire CH system is nearby, the L is covered, so a Viessmann Compact or the Baxi mentioned earlier will work, needing just the supplied SL, N and earth.
I fully understand that , but as I understand it , the question was how to provide a pump over-run with only 3 wire's going to boiler , I have seen it done on a couple of potty suprima's year's ago , most or all manu's would not allow this method ?? incidentally I believe the biasi band B condensing system's boiler does not reguire a pump over run , S Live only !!
Were about's in Surrey are you ????
Were about's in Surrey are you ????
Sponsored Links
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
