Automatic Bypass Valve Query

[doitmyself]

Hi. Thanks for the reply. Did you see my pic and post number 3? Does the position looks wrong ?

If pipe A in the pic below goes to the boiler, it's piped wrongly. But if pipe B goes to the boiler, it's correct.

 

[John.g]

If pipe A in the pic below goes to the boiler, it's piped wrongly. But if pipe B goes to the boiler, it's correct.

View attachment 36944

Correct, and of course also assumes that B is on the boiler flow, that test above should prove it one way or the other but surely it should be also possible to trace those lines, if not already done so.

 

[Tigermad]

Hi. Pipe a and b are the same pipe. If you mean directions then a goes into the loft to the unvented cylinder and b goes down towards the boiler. The whole pipe has return written on it.

 

[John.g]

Hi. Pipe a and b are the same pipe. If you mean directions then a goes into the loft to the unvented cylinder and b goes down towards the boiler. The whole pipe has return written on it.

Can you just do one thing please and post back, turn up the cylinder stat to max (normal setting should be 60C) and see which one of those pipes gets hot first.

 

[John.g]

Hi. Pipe a and b are the same pipe. If you mean directions then a goes into the loft to the unvented cylinder and b goes down towards the boiler. The whole pipe has return written on it.

Reading your reply again, literally, the (and as I suspected) zone valve if fitted on the SUPPLY or FLOW to the hot water cylinder coil, the RETURN is the vertical pipe so the ABV is the wrong way round?.

Here is your image with arrow.

 

[doitmyself]

Hi. Pipe a and b are the same pipe. If you mean directions then a goes into the loft to the unvented cylinder and b goes down towards the boiler. The whole pipe has return written on it.

A and B are actually two separate pipes which connect to the motorized valve; but that's not important. Your second sentence answers my question as pipe B goes to the boiler, so the bypass is installed correctly.

As for checking if the bypass is set correctly, yes, it's the short length of pipe between the bypass and pipe 'B' which you need to feel. However, if the motorized valve from the HW cylinder is closed so there is no flow coming through the MV from pipe A, then you can feel pipe B to check if the ABV is opening.

If pipe B is the HW return to the boiler, where does the heating return connect?

 

[JTplumbingservices]

If pipe A in the pic below goes to the boiler, it's piped wrongly. But if pipe B goes to the boiler, it's correct.

View attachment 36944

Where is the boiler and pump in relation to this pic?

 

[Tigermad]

Where is the boiler and pump in relation to this pic?

Hi. Sorry for the late replies I did not get notifications. The boiler is downstairs under the stairs directly below the airing cupboard. The pump is in the boiler I don't have one seperatesl as far as I know

 

[Tigermad]

A and B are actually two separate pipes which connect to the motorized valve; but that's not important. Your second sentence answers my question as pipe B goes to the boiler, so the bypass is installed correctly.

As for checking if the bypass is set correctly, yes, it's the short length of pipe between the bypass and pipe 'B' which you need to feel. However, if the motorized valve from the HW cylinder is closed so there is no flow coming through the MV from pipe A, then you can feel pipe B to check if the ABV is opening.

If pipe B is the HW return to the boiler, where does the heating return connect?

Not sure where the heating return connects sorry

 

[Tigermad]

Straightforward enough.
1. Shut off the ABV, turn the setting knob clockwise to o.5
2. Ensure all zones (if fitted) on, and all TRV.s fully open.
3. Turn any/all room stats to max. (my suggestion)
4. Ensure boiler is actually firing or cycling on/off.
5. Very slowly turn ABV setting knob anticlockwise until the outlet pipe starts getting warm/hot.
6. Turn ABV setting knob clockwise by 1/2 a turn.
Forget the rest of the instructions for awhile and you can revisit them later.
Re 5 above. IMO, you can expect the pipe(s) to start to get warm at ~ setting 0.3 to 0.2.

Hi. I've done your test and the pipe only stats to get very slightly warm at around 0.25. Even when fully open the pipe is only slightly warm is that correct? By slightly warm I mean nowhere as hot as the flow going into it.