Bryan Williams
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I just looked at a couple of YouTube vids and someone said ideally on the return, that's the only reason I pointed to that one, pick a pipe, I'm open to advice
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Seadog
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??
Pigeon_Droppings2
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I've also got a busted expansion thingy...as a work around I emptied most of the water out of 1 radiator and that acts as the expansion vessel.
It was only a temporary fix....2 years ago...still working a treat
.
It was only a temporary fix....2 years ago...still working a treat
.
Kayos
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Fairly complex subject, each system has a natural neutral point where flow is minimum and the return starts to have an effect. Additional neutral points can be created with tees, such as a cold feed on an incorrectly piped system, thats why they block at that point
As the vessel moves, if it's on the flow it can cause the water to change speed, creating a neutral point that can block the pipework, however in the ops case, the pump in the boiler will likely overcome this
There is a huge amount of science behind central heating, I have done advanced hydronics so have a good understanding, I just like to help where I can, without getting into the science though
Seadog
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Hmm, to my mind the water is either flowing or it's not. With an incorrectly regulated system I can understand dead spots, cold rads for example. But I can't see how the position of the PV affects things.
Kayos
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Complicated subject, Google advanced hydronics
Bryan Williams
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Looking like im doing it myself.. It seems to scare plumbers off..
Plan is, turn off the power isolate water, drain from front room rad, remove elbow on flow and replace with tee reducing to 15mm and then to vessel hung below.
Refill system top up with fernox, bleed, set pressure, keep checking for pressure and air in rads, does this sound anything like?
How would I go about finding the right size vessel? I've googled replacement Worcester Bosch ones but the spec doesn't give up much..
Cheers.
Plan is, turn off the power isolate water, drain from front room rad, remove elbow on flow and replace with tee reducing to 15mm and then to vessel hung below.
Refill system top up with fernox, bleed, set pressure, keep checking for pressure and air in rads, does this sound anything like?
How would I go about finding the right size vessel? I've googled replacement Worcester Bosch ones but the spec doesn't give up much..
Cheers.
Just a quick one - what's the process for checking pressure in the expansion vessel? Does it need to be disconnected from the system or prior to system fill or with the system open (i.e. bleed point open so pressure is neutral)? Not sure if it matters but may be worth someone who knows clarifying for Bryan.
gaz1
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undo the 15mm feed silver fit a 15mm tee you will need a length of pipe
drill through the top or dont bother your choice
trim copper pipe to fit into tee silver compression should be the same as normal compression nut not always though
1 straight you will need the nut from it fit pipe inbetween and tighten dont over tighten the olives are crap nowadays
tee into expansion tank or pipe inside of the unit and refit where needed
Bryan Williams
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Bryan Williams
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Did the obvious thing in the end re finding vessel size, phoned Worcester Bosch.
Apparently it's just a six ltr vessel at the back of this boiler,used to be a 10ltr but they went smaller. Advised 12 or bigger the better according to him, which I was a bit surprised at, I thought it would be more critical.
Apparently it's just a six ltr vessel at the back of this boiler,used to be a 10ltr but they went smaller. Advised 12 or bigger the better according to him, which I was a bit surprised at, I thought it would be more critical.
Pigeon_Droppings2
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At a guess I'd say they fit the smallest they can get away with. Bigger should mean the system pressure is more stable from hot to cold (is range)...but I'm no plumber...just guessing based on its purpose.
Seadog
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To check the expansion vessel the system needs to have no pressure in the heating circuit. If you need to repressurise at any time,, go slightly over since, in my experience you lose pressure detaching the valve adaptor, and the volume in the vessel is not very great.
