Boiler pipe layout confusing

[davidmpye]

Hi,

I've moved in to a new house.

I've been trying to get my head around the boiler cupboard plumbing layout - I have fitted a magnaclean to the Return of the boiler loop, which I'm pleased with.

However, the thing I'm mystified about is the pump location and what it's doing.

The background: System is a pressurized system, with a condensing, non-combi boiler. There's a pressure 'tank' on the upper left of the cupboard.
It appears to be an S-plan system, with the FLOW going to two motorized valves, to direct feed either the hot water tank or the central heating (or both).

However, the pump is confusing me. Its' inlet is a pipe from above the ceiling, and it isn't clear what it is, but it's the pump OUTPUT that really confuses me. The pump 'pumps' right to left in the photos, and has a one way valve on its' output to prevent backflow.

The blue-handled stop lever appears to be the mains cold water feed to the hot water tank INLET, and a filling loop is tee'd off it to allow you to refill the loop.

The pump output appears to feed into a tee which then leads to the INLET of the HW cylinder, downstream from the mains inlet. This surely can't be the case, so I am sure I must have misunderstood something? (Yes, the previous installer must've really liked copper crimp fittings....!)

Any thoughts would be very welcome!

David


David

 

[Exedon]

That pump is a secondary circulator gives you instant hot water at taps.
B t w nothing at all wrong with press fit!

 

[davidmpye]

I guess not, but there's a lot of them, and the extra cost over solder fittings must have been significant!

Thanks for the reply, that now makes perfect sense. I didn't realise we had a circulator pump, so was trying to understand why something seemed to be feeding back into the HW cylinder inlet.

David

 

[Exedon]

I guess not, but there's a lot of them, and the extra cost over solder fittings must have been significant!

Press fit fittings are more expensive but the time savings especially in plant rooms oe similar are considerable.
Plus no solder flux or blowlamp gas.
Add to that the advantage of no hot work.

 

[Why Not Indeed]

What's going on here?

 

[Harry Bloomfield]

Tundish..

 

[Nige F]

tunpipe

 

[Harry Bloomfield]

tunpipe

Never seen one before, how does that act as a telltale? You would not see the water dripping.

 

[Nige F]

You're right Harry , but maybe it sort of complies ?