Central Heating System Confusion

[doitall]

I'd hate to think how it's wired.

 

[DeltaT2]

I'd hate to think how it's wired.

Very true DIA, very true!!!

 

[Alfie25]

Seen this a few times with BG systems, you can't select CH on it own. Daft I know but it's done to speed up the install. As said you could sort it out with a 240Vac/240Vac SPST relay or just wire in the HW off on the programme & NO or SAT on the cylinder stat, as it should be.

I think you've hit the nail on the head here. The system is fully pumped with a 3 port valve but there's no wire going to the programmer from the 3 port valve to say HW off. I don't think the wiring is in too much of a state - like you say, they've cut this corner to save time and the last owner of the house mustn't have been bothered. I wish you were in my area Delta as you sound like you know what you're talking about! Out of interest what do you call yourself? A heating engineer? Just asking as I'm having trouble finding someone to come out and sort it.

And what does DIA stand for?

 

[mysteryman]

DoItAll presumably.

If you are in the house wanting central heating, it is likely that you will want hot water as well. That's why CH only is sometimes not offered.

 

[mysteryman]

You can't do that with a Y plan unless it's wired wrong Dickie

Oh I'm sure it's not wired like a 'Y' plan DIA. Ever seen it where they use the mid-poss valve as a divertor valve?? The grey & white is connected together!! Gawd knows what that does to the Resistors or Diode??..................

Doesn't harm them at all!

 

[DeltaT2]

Seen this a few times with BG systems, you can't select CH on it own. Daft I know but it's done to speed up the install. As said you could sort it out with a 240Vac/240Vac SPST relay or just wire in the HW off on the programme & NO or SAT on the cylinder stat, as it should be.

I think you've hit the nail on the head here. The system is fully pumped with a 3 port valve but there's no wire going to the programmer from the 3 port valve to say HW off. I don't think the wiring is in too much of a state - like you say, they've cut this corner to save time and the last owner of the house mustn't have been bothered. I wish you were in my area Delta as you sound like you know what you're talking about! Out of interest what do you call yourself? A heating engineer? Just asking as I'm having trouble finding someone to come out and sort it.

And what does DIA stand for?

Ah, DIA is my very good friend 'doitall'. A Gentleman that has forgotten more about our trade than I know, that's a very helpfull fund of knowledge & a highly respected member here...........

I'm the infamous Sir D.ck Puller, I'm a time-served Plumber/Heating Engineer & Cultural Attache for Glasgow Gorbals.

I hope you get sorted out & I'm pleased I could be of some help.

 

[DeltaT2]

You can't do that with a Y plan unless it's wired wrong Dickie

Oh I'm sure it's not wired like a 'Y' plan DIA. Ever seen it where they use the mid-poss valve as a divertor valve?? The grey & white is connected together!! Gawd knows what that does to the Resistors or Diode??..................

Doesn't harm them at all!

Thanks MM, that's reassuring.