Fitting new 5111603 PCB to suprima 50

[MANDATE]

I don't quite follow your findings.
W, M and H surely stand for Water, Midway and Heating, which equate to bottom, midway and top, or top, midway and bottom.

So 'HW and CH off switch points to H'. Ok the valve stays in the last position when turned off, so being at H is understandable.

'HW on on its own switch, points to the top at M'. With no CH on and HW on demand the return spring should unwind the motor/valve/quadrant to the W position. not M, also M (midway) surely can't be at top

HW and CH on together switch is at midway W. It should be at midway if both are in demand, but midway is M.

CH only switch is back at H. This is correct and if boiler does not light then micro switch at fault.

The micro switch is mounted in the actuator head and I think you would be better getting the whole head replaced.

This type of fault will not allow CH on its own, when HW is called for with CH, the boiler is lit from the cylinder stat not the micro switch. so you do get CH, but only until the HW is satisfied and is cut off and the valve moves to CH (but does not light).
You can understand when there is CH at times it does become confusing. if the mecanics of the valve are not understood.

Another simple test with both HW and CH is to either (a) alter the cylinder stat to create a demand. Or (b) Run off some HW, which creates a demand.
You will find the boiler will light and you will get CH, but only until HW is satisfied.

 

[Grindstone]

Ok think this may make a bit more sense. I read the switch sideways on from left to right, (as you would expect). If I had been on the other side of it, then M would be W and W M, i.e. the other way round.

So CH and HW off is pointing at H

CH off and HW on is pointing at W

CH on and HW on is pointing at M

CH on and HW off is pointing at H, but not coming on, so the micro switch, in the actuator head. Where is the actuator head? Can I change that?

Big thanks for all the help here, I do feel relieved that this problems looks like it is moving now and may even get fixed

 

[MANDATE]

The actuator head is the top part of the whole 3 port valve. that you've been testing
Don't know what make your valve is, but can usually just change the head without changing the valve. Fairly straight forward.
Isolate boiler power and remove fuse. Remove securing screws and lft head off the valve spindle. Remove the related wires from the 10 terminal box. ( should be White, Grey, Orange, and Blue. and a green earth if there is one) Fit replacement head in reverse order.

I took an easier option instead of messing around in the 10 terminal box. I mounted a 25mm deep switch patress on the wall. cut the existing cable and put the wires into a 5 terminal strip mounted inside the patress. Put the new cable into the strip like for like and fitted a blanking plate.
This will have a distinct advantage in the future when testing. Especially if the micro switch is suspect, cause I can easily link white to orange to test.

 

[Grindstone]

Sorry for not replying earlier, I've been away.

I've bought a new actuator and I'll be fine changing wires etc over. The problem I have now is how do I get the exisiting switch detached?

Looking at the new one is not giving me any clues, will the old one simply pull off? I can't see how its attached to the pipe work.

Untitled

• Grindstone
• 15 Dec 2008
• 1

Untitled

• Grindstone
• 15 Dec 2008
• 1

Untitled

• Grindstone
• 15 Dec 2008
• 1

Untitled

• Grindstone
• 15 Dec 2008
• 1

 

[MANDATE]

I've bought a new actuator and I'll be fine changing wires etc over. The problem I have now is how do I get the exisiting switch detached?

Looking at the new one is not giving me any clues, will the old one simply pull off? I can't see how its attached to the pipe work.

Don't know about your actuator, but I doubt if it will just pull off.
On photos 1 and 4, I can see what looks like solid brass pillers behind the head. Securing screws have to secure to something and apart from these pillers it seems to be space.
Look at your new one to see if any holes that match the position of pillers.
Perhaps if you stated the make of the actuator head, someone may know the answer.

 

[Grindstone]

The one that is currently on is:

ACL Drayton
Mid position valve 22mm
679H340 - 3OLO

And the repalcement actuator is acl drayton MA1

They look similar, but are not an exact match, as the back of the new one looks different to the back of the one that is on, but they are approx the same size, shape etc

 

[MANDATE]

The one that is currently on is:

ACL Drayton
Mid position valve 22mm
679H340 - 3OLO

And the repalcement actuator is acl drayton MA1

They look similar, but are not an exact match, as the back of the new one looks different to the back of the one that is on, but they are approx the same size, shape etc

Suggest you do search for author 'goosander' on this forum. Seems he had similar problem and was informed the older valve did not have removable head, but the latest model does.
Based on that it seems you need a complete valve with head and not just the head. I noted a technical helpline 0845 130 5522 if you think its worth enquiring.

 

[Grindstone]

Hi Mandate,

Done the search and see what you mean. The thread does mention that the microswitch is interchangeable though? Are you able to tell me what that is? I guess if I change it and it works great, if I change it and it doesn't I can put the other one back on?

A full drain down and change of valve is beyond me, happy to get a plumber although I suspect they may well be in short supply at the moment

Thanks very much for your help, which ever way this goes now it would seem that this is the issue and it can be resolved.

Neil

 

[matt1e]

hi grindstone
I suggest you check your your wiring first especially the wiring of the room stat as it seems to be wired in series with the hot water circuit as opposed to the central heating

 

[Grindstone]

There are only two wires for the room stat (Drayton digistat *2) the heating won't come on unless there is a demand for heat from the stat and the water and heating are both on, the issue is that when the temperature on the stat is reached the heating stays on, secondary issue is that the HW must be on to get the heating on.

I thought the tests mandate advised were conclusive, i.e. it has to be the microswitch in the actuator, as it moves through all positions, just isn't getting the correct instructions due to the dodgy switch. Do you not agree?

 

[matt1e]

yes I agree with mandate with regards to the diagnosis of the valve but this assumes everything is wired up correctly and from your description the room stat is definitely not. and you have also had your time clock changed
try this
1) turn off all power to the system via its isolating switch(this will or should allow the valve to return to its resting position ie at the H position)
2) set HW and CH to off at the time clock
3) set the room stat to off and turn the cylinder stat up
4) turn on power and select HW on the time clock the valve should stay at rest and the boiler should fire if not this is your first wiring fault and nothing to do with the valve (yet)

matt

 

[Grindstone]

Ok, done all that, power off to everything and the valve points at H, HW on by itself, with the room stat down so there is no demand for central heating and the boiler fires, the valve has moved to W, I guess for water.

 

[MANDATE]

yes I agree with mandate with regards to the diagnosis of the valve but this assumes everything is wired up correctly and from your description the room stat is definitely not. and you have also had your time clock changed
try this
1) turn off all power to the system via its isolating switch(this will or should allow the valve to return to its resting position ie at the H position)
2) set HW and CH to off at the time clock
3) set the room stat to off and turn the cylinder stat up
4) turn on power and select HW on the time clock the valve should stay at rest and the boiler should fire if not this is your first wiring fault and nothing to do with the valve (yet)

matt

Hi Matt! what makes you think the room stat is not wired correctly.?
If the room stat was faulty then valve could not move to mid position, but it does and there is CH along with HW, but this will only be until HW is satisfied, when it should move to CH only position.
Well it is reported as moving to all positions, so that means the 'grey' wire needed to complete the move is also live, so nothing wrong with wiring.
This leaves the micro switch. When this is triggered, the orange wire becomes live to fire the boiler, but in this case it doesn't

 

[matt1e]

hi
sorry on my previous post regarding the valve I put H at rest I should have put W (I take it the valve has a H an M and a W -the M should be in the middle)
so to recap
with all power off (remember to switch off at the main switch)
the valve should return to rest (w)

HW on, cylinder stat up, CH off and room stat down
does the boiler fire?
does the valve move if so where to?

matt

 

[matt1e]

hi mandate
because on a earlier post it was stated that BOTH the room stat and the HW had to be operated for the boiler to fire ie with HW selected boiler still would not fire unless the room stat was turned up