Plumber telling me porkies? Drayton ZA5 dud needs full drain

[Agile]

Based on the second picture, the little black button is I think the later design which can be pressed to turn and remove the head.

As you have been told, the body may have a tight shaft causing it to stick. In that case its best to replace all of the valve.

However, that model is not very reliable and often the problem is just in the head.

If the head is removed, it should be possible to turn the shaft with your fingers. If thats the case then just the head can be changed.

Any competent heating engineer would check that before giving a price as changing the head is a simple job hence our lower price of just £144.

Tony

 

[jdamnation]

Does anyone know if I can just take this sucker off? I've turned off the system. Safe for a 'non plumber' or something for an expert!?

I was thinking - I'll take it off, and let him come in to replace it - I'll then tell him the 'good news' that I figured out how to remove it without draining the system!



I can see the small button on the front but I think there is some sort of other lock clip elsewhere.

JD

 

[Agile]

I had my motorized 3-port valve replaced last year (it was the old type with a non-removable actuator). The total cost - parts (Honeywell valve and a new ball valve in the F/E tank) and labour was about £160. Time taken about 2 hours.

Pretty much in line with the price that I quoted after taking into account that it was a three port and the Honeywell is a bit more expensive than the Drayton!

I would have expected that you would have done that simple job yourself Dave!

Tony

 

[nickso]

what's all this fannying about and talk of 3 hours to change a two port valve?

jdamnation, just push the black button and lift the head off forcefully. the fault is likely to one of three common issues on this valve.

first the spindle on the brass body has siezed. if so spray it with lubricant and work it back and forth until it's free again. they often last months or years if that is done. if it is leaking through the spindle it will need replaced.

second the return spring posts break off inside the head and the microswitch stays closed leaving the boiler on. can be repaired but new heads are not expensive so most dont bother.

third, the microswitch is faulty. new microswitches are available for pence.

if the body does need changing then change it on it's own and keep the current head....should take no more than an hour unless it's in an awkward position.

 

[Agile]

It could take less than an hour to replace the body only, but thats only if draining and refilling is easy.

When draining I close off the rad valves when they are working and so I only have to drain the pipework. That can be just 20 litres which I can do from the valve.

In other cases with stuck rad valves and a stuck drain cock it can be a much more involved job and take 1-2 hours. In fact on new cream carpets I might decline the job.

Funny how some people spend £2000 on cream carpets but dont get jammed rad valves replaced for £200 !

Tony

 

[D_Hailsham]

I would have expected that you would have done that simple job yourself Dave!

There's enough unemployment where I live without me indirectly contributing to it. In any case, I had already diagnosed the fault so all my tame plumber had to do was change the valve!

The faulty ball valve only came to light when he tried to refill the system. The valve was stuck shut - which shows that the water level in the F/E tank had not changed for years.

 

[nickso]

It could take less than an hour to replace the body only, but thats only if draining and refilling is easy.

When draining I close off the rad valves when they are working and so I only have to drain the pipework. That can be just 20 litres which I can do from the valve.

In other cases with stuck rad valves and a stuck drain cock it can be a much more involved job and take 1-2 hours. In fact on new cream carpets I might decline the job.

Funny how some people spend £2000 on cream carpets but dont get jammed rad valves replaced for £200 !

Tony

again, unnecessary fannying about. bung the header, drain it at the valve, replace, unbung, job done. if it's a sealed system it often takes less than 20 minutes.

the only time it should take more than 1 hour is if the valve is in an awkward position, siezed on or there is no movement in the pipes.

 

[Whitespirit66]

Keep going. Should be able to get 4 or 5 pages out of this one. Things are slow here too.

And, OP. If you are replacing the whole valve, please spend the extra few pennies and get the Honeywell valve. Not this Drayton nonsense.

 

[jdamnation]

Now we're getting somewhere!

Obviously the experts are all working late and don't get up until noon!

Right then - here is what I have found.

Popped the button, thing just comes off. Bit dusty, isolated mains had a look inside, nothing really exciting in there.

The identical HW one seems to work like this:

Turn system on.

Note actuator is in 'A' position - closed.

Turn HW on - little lever moves from A to B. We have HW!

Turn HW off - little lever moved back from B to A - HW off.

That's all great. Now - it's evil twin - the CH.

Turn CH on..... nothing. Little lever still on A.

Move the plastic catch to force the valve to B. CH starts working!

Turn CH off..... nothing. Have to switch off system in order to get lever back to A.

Does that offer up any more clues as to where the problem might be?

JD

 

[nickso]

this expert was busy getting drunk.

take the head off and try to turn the spindle with your fingers. it only moves 30-40 degrees but should be easy to turn. if not it needs lubricating.

if that's ok then i would be looking at changing the motor in the head but you have to confirm the motor is getting power from the clock first really.

 

[jdamnation]

Yep I can turn it easily - actually feels a bit loose!

So just a new head it must be then. Compete re-drain my *ss.

This bad boy is quite close up against the wall - I'm wondering if the honeywell ones are any bigger - might not fit?

JD

 

[jdamnation]

The motor must be getting power from the clock, because after I force the CH setting from A to B - when I switch the mains off - the lever moves back to A.

If there was no power from the clock I wouldn't be able to move it to B - it seems like it needs power to hold it there....

JD

 

[nickso]

a honeywell will fit if a drayton does but you don't need a new valve or even the head. difficult to tell from here but my money is on a shagged motor, that can be replaced on it's own or you could probably change the head yourself if you feel confident with swapping 5 wires.

remember you need to confirm 240v to the motor before we can be sure it's that.

 

[nickso]

The motor must be getting power from the clock, because after I force the CH setting from A to B - when I switch the mains off - the lever moves back to A.

If there was no power from the clock I wouldn't be able to move it to B - it seems like it needs power to hold it there....

JD

240v moves the motor to b position. the valve is spring loaded so moves back itself when the power is removed.

 

[jdamnation]

Right so if there was no power - if I forced the lever from A to B - it would just slide back to A again right?

Because it's saying on B and going back when I cut the power - I must have 240V going to the motor right?

JD