Leaking 3-Way Valve ?

[rideforever]

On my old Glowworm Xtramax ! if it's only the hot water that is on (summer setting) then the nearest radiator mysteriously warms up when hw is drawn. And what has been discovered is that draining the boiler means also draining all the radiators which takes a long time, or shutting the radiators off.
So I am assuming this means that the 3-Way valve has gone ?
Is it important ?
Because these symptoms are not causing much inconvenience in general, the nearest rad is now shut off in the summer that's all.
Or is it a bigger problem that needs sorting out ?
Cheers

 

[terryplumb]

The 3 port valve needs replacing ,before winter sets in preferably. Its not likely to get any better ,and may well get worse.

 

[rideforever]

The 3 port valve needs replacing ,before winter sets in preferably. Its not likely to get any better ,and may well get worse.

Will it cause further damage ?

Considering the boiler otherwise works normally, is it just the 3 way valve and not the 3 way valve motor ? Or could it be both ? How can I tell ?

 

[terryplumb]

Quote.".will it cause further damage "
What damage has been caused so far ?
What exactly do you mean by " leaking 3 way valve " ?
If you put central heating on ,do all radiators heat normally ?

 

[rideforever]

Quote.".will it cause further damage "
What damage has been caused so far ?
What exactly do you mean by " leaking 3 way valve " ?
If you put central heating on ,do all radiators heat normally ?

Yes they all work normally and so does the HW.
However, if only the HW is on then the first radiator nearest the boiler is always warmed even though the heating is off.
And .. last year a plumber changed a part .. in order to do so he found he had to drain down not only the boiler but all the radiators. Just draining the boiler did not work, the water just kept on draining out until he realised that the radiators were also being drained. Later he realised that by shutting off the valves to all the radiators in the house then the boiler could be quickly drained. Therfore the rads are not isolated from the boiler.
Thats all I know.

 

[terryplumb]

The 3 port valve when in domestic hot water position ,should close the port to the radiators ,so rads don't heat. Sounds like yours isn't fully closing. As long as your rads ,and domestic hot water heat OK then you don't need to worry too much. As we are nearing the winter period it would be prudent to have it looked at ,its Sods law that if its going to get worse ,it will when its freezing cold and you can't get an engineer !!! It may well go on as it is for ages ,no way of knowing.

 

[rideforever]

Sounds like yours isn't fully closing.

Thanks.

One thing that it does seem to do is ... for instance with the HW, when you run the tap the boiler comes on and when you shut off the HW then the boiler stops and the restarts for a second and then stops. And it's off.

I do not know why it stops starts stops. Rather than just stopping. And I am wondering if the not fully closing 3 port valve could be the reason ???

 

[terryplumb]

When was the boiler serviced last ?
Its normal for the boiler to fire up when hot tap is opened ,as its store of hot water is depleted, but shouldn't keep going off / on/ off etc.
You should engage an engineer to check it out and sort the diverter as well.