Central Heating Problems....... Fixored

[GingerMagic]

Thats a better price, thanks Peter, although I may spend a few quid more to get one from work tomorrow to save time and postage fees.

Am I better of getting a cheaper pattern part or a genuwine Honeywell or Drayton etc, for longevity reasons?

I'm assuming the fact that the manual slider goes limp when I lift it actually points to mechanical failure and not electrical...

[grasmere59]

That a Honeywell valve,if you look at the gap between the base of the silver casing of the valve and the brass body of the valve you will see little brass hex studs,the steel body is held to those with 2 x Phillips head screws which you can probably see with a mirror,if you undo those 2 screws you can lift the head off and hold it in your hand to work on replacing the motor,the lever you push across latches by lifting it up as the spring is returning it,as a make do in the past I have wedged the lever over to hold the valve open and put the hot water on constant on the programmer to get a bit of heat in the rads.

[GingerMagic]

That a Honeywell valve,if you look at the gap between the base of the silver casing of the valve and the brass body of the valve you will see little brass hex studs,the steel body is held to those with 2 x Phillips head screws which you can probably see with a mirror,if you undo those 2 screws you can lift the head off and hold it in your hand to work on replacing the motor,the lever you push across latches by lifting it up as the spring is returning it,as a make do in the past I have wedged the lever over to hold the valve open and put the hot water on constant on the programmer to get a bit of heat in the rads.

Thanks Brett - I'll look into this when I replace it, maybe keep it as a spare if I don't somehow balls it up...

A new head is about £10, but I'm not sure if I need one with a mid part or if they are all the same.

The lever has no resistance when I lift it, so the rads won't work as there isn't a mechanical means to push the microswitch, otherwise I would wedge it too......

Do I need to pull out a fuse before removing the head, or can I get away with turning off the stat and the programmer? Also, can I remove the head and put a set of mole-grips on the shaft?

( I just wrote ' shaft'... )

[grasmere59]

I don't think you'll be able to get a replacement head for £10,perhaps a motor for that.The "shaft" is like a screwdriver blade shape that locates in a slot in the plastic driveshaft that is driven by the motor,it only rotates through about 90 degs from stop to stop,it's a job to explain but inside the valve itself is a rubber ball on an arm that moves through and arc to shut off either the supply ports to the hot water or the heating or it sits in the middle to supply both,i have had it in the past where this ball has swollen (oeer missus) and jams and that will mean a need for a drain down and a complete valve replacement.The tell tale for this is slight heating up of the radiators when the hot water is on.I would check for power to the orange wires to the motor when the roomstat is switched up and down first,you can usually get the probes of the multimeter in the little joiners from the orange wires to the loom of the valve.

[GingerMagic]

Okay - I can understand how the valve works - its a bit like a mini 'swing-ball' inside the tee piece and diverts a full frontal flow either left, right or both of it stays in the middle....

Am I better off getting a complete new valve, and keep the old one for experimenting - or should I take the plunge and get a multimeter and try to pinpoint the fault with the old one although access is a bit poo

[grasmere59]

If it was me I would be changing the complete valve,you would only need to part drain the system to just below the valve so not too big a job.theres one here http://www.ebay.co.uk/itm/Honeywell-V40 ... 3f4067fd28

[GingerMagic]

Okay, I'll look at getting it replaced.

Are Boss any good, £43 and I can bring it home tomorrow....

I appreciate everyone's input.

[grasmere59]

To be honest Kelv I've never fitted a BOSS valve so I can't comment on the quality/reliability of them,i've always used Honeywell where possible but having said that I've had a few of them fail in the past.Needs must and you need the heating on and it'll come with some sort of warranty so I'd go for it.

[GingerMagic]

Well, I've set the valve to Manual and I now have heat in the rads albeit very gradually. Does this mean I won't get any hot water now..??

[grasmere59]

Feel the pipes either side of the diverter valve and if there both getting hot the chances are you'll get hot water,if you feel the pipe leaving the cylinder (the return) it's the one directly below the one that goes from the valve into the cylinder,if that is also hot you will definitely get hot water.

[GingerMagic]

I checked that earlier, and the pipes are all hot to the point of 'ouch' but I didn't know how much was heat transfer....

I'll check later on tonight - if I've got hot water and central heating then I'll replace the valve when I get some pennies together - if I have to sacrifice hot water for heating and vice-versa then I'll replace the valve sooner.

Thanks again,
Kelv.

[grasmere59]

The only problem I can see is that if you running the heating using the hot water control is that when the hot water cylinder stat is satisfied the boiler will shut down and the heating will go off.Looking again at the pics you posted the valve does not look like a Honeywell valve but a Honeywell "type".

[GingerMagic]

You are correct - its a local plumbers merchants own brand.

The hot water is really hot ( set to 60c on the boiler ) and the rads are also piping hot - to the point I have turned the hot water off so the kids don't burn themselves....

I haven't checked the stat on the cylinder but I assume the boiler over-rides it?

[grasmere59]

It's a job to tell without looking at it and seeing what is actually controlling the system with the valve in the manual position,with what you are saying it would seem that the heating/hot water is now being controlled by the boiler flow temp and not the tank stat,at least you have some sort of heating now until you can get it properly sorted.With the aftermarket valve my rubber ball theory might go out of the window as some of the aftermarket ones use a brass paddle as a diverter in the valve.

[GingerMagic]

I see - a bit like the 'cup' thing inside an isolator valve?

I've phoned my plumber acquaintance earlier who I've known for around 10 years ( I used to deliver kitchens and bathrooms ) and he has offered to pop in tomorrow to have a look before taking the plunge and going for a drain down valve swap.