Which one flow?
- Thread starter theflyingpig
- Start date
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Pipe on left appears to be heating flow so arrow wrong way round pipe on left looks like old cylinder return.
The pump always flows up into the 3 port valve, so the pipe out of the top of the pump is the flow into the bottom of the 3port and then out left and right to the CH and HW (A+B), they are flows too.
Gate valve looks to be an old redundant manual bypass but that open ended return shouldn't be left like that in case the gate valve starts to leak - the gate valve should be capped off at the bottom if that return is now redundant/disconnected too.
Gate valve looks to be an old redundant manual bypass but that open ended return shouldn't be left like that in case the gate valve starts to leak - the gate valve should be capped off at the bottom if that return is now redundant/disconnected too.
Thanks both. Makes total sence..
I'm removing all of this but need to know how to connect up new system (s plan) into existing ch plumbing....
I'm removing all of this but need to know how to connect up new system (s plan) into existing ch plumbing....
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Remove the 3 port and replace it with a 22mm tee. - Then place the 2 ports further downstream on the pipes - so the downwards left leg for the CH 2 port and the right upwards leg for the HW 2 port (if there's space).
Job's a guddun
Job's a guddun
Presumably you're going to replace the HW cylinder? What is the bypass round the pump for?
It would probably have been an old manual system bypass onto the HW primary return, wasn't really needed given it's a 3port, unless all the rads had TRV's
But it shouldn't go to the pump suction, should it? The idea of the bypass is to maintain a minimum flow through the boiler, if all the TRVs etc close (as you obviously know).
It is yes ... but that's not the negative side of the pump - the positive side of the pump is out of the top upwards towards the 3 port above - so the bypass is on the positive side and bypassing the 3 port back to the return. Even then though, at the moment it's redundant.
But IMHO it shouldn't go back to the pump return, but to the boiler return. It's the boiler we're trying to protect from low flow, not the pump (or at least not so much!)
Looks to me like it's going into what was the Cylinder Primary return.
You're right but the pipe it's connected to isn't the flow pipe into the pump - as suggested by @Hugh Jaleak , the bypass pipe from above the pump , is through the gate valve and then it's connected to what looks like it was the primary return (back to the boiler) from what must have been the old cylinder, which currently is open ended.
Zoom in on the pic and you'll see the pump and flow pipe into it is actually behind the pipe that the bypass is connected to. As also suggested though, at the moment the gate valve must be shut down as the old return pipe it's connected to is open ended and therefore must be disconnected from the system or the system is drained, but if not and the gate valves then leaks, then it's going to get wet in there
You're absolutely right, my bad. I hadn't noticed the one pipe hiding behind another.
Interesting stuff! Yes, system is currently drained.... Ripped everything out, have new unvented tank running on immersion and will fit new boiler and s plan later in the year, connecting up to flow and return here.....
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