Reverse Circulation

[cassis01]

Hi there

I would be grateful for any assistance you could provide. Boiler is an Ideal Classic, fully pumped on a Y plan system in a bungalow. Boiler and cylinder are downstairs and pump,tanks and valve in loft. Completely renewed professionaly from a gravity system in the late 1990's. The system was providing heating via the rads when only hot water was demanded. The complete 3 port valve was exchanged on Monday although the problem has now returned. I tried to just change the actuator head but the problem still remains. I have heard it may be a reverse circulation problem but could the new head also be at fault ? Should I try exchanging the head or is there an easy way to check for reverse circulation ?

Many Thanks in advance

 

[doitall]

Can we assume it's done this for the last 15 years or just started.

Probably find the valves been fitted the wrong way round or wired up wrong.

 

[ChrisR]

How many rads get hot? Reverse cculation usually does it on only a couple.

Pump's not in backwards is it ? That would cause reverse circulation which could heat all the rads! That's cos the valve only works properly one way round.

 

[cassis01]

Problem only recently started. The valve wiring was checked today and valve found to be moving correctly. Valve also fitted round the correct way, b for bath. Apparently a rad was added in the last couple of years and this, somehow, is causing the system to back circulate. With hot water only on, the pipes to the hall rad, start to heat up, return pipe getting hotter first. If heating is also turned on then the return cools slightly and the flow pipe heats up. Hope this makes sense.

Thanks for all the help Looks like some repipeing is needed.

 

[doitall]

I have a slight problem with your wording.

if the problem is the new rad then the problem would exist from then and not recently.

I would expect by the sound of it and you can test by turning that rad off, that the heating flow has been taken off before the motorised valve, or the return has been connected to the common return

 

[fitz1]

Wouldnt a non return valve surfice.

 

[doitall]

Wouldnt a non return valve surfice.

Possibly if he can ID the exact pipe where the connection is wrong, first test would be to turn that rad off on it's valve and see if the circulation stops

 

[Dermo1]

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