Issue with Mid Position Actuator

[Booie]

Hi there,
I've been having some issues with my Hot Water and Central Heating for a while now and we've had a plumber out twice who seems to fix the problem we were having at the time but then another issue arises soon later. So I was wondering if anyone could advise me to what the actual problem may be?

My Mid Position Actuator is a Drayton MA1 and my Timer is a HoneyWell C21.

At rest the lever of my Mid Position Actuator sits at H.

I then turn on just the water, this leaves the lever in the H position.

Then turning on both (CH and HW) moves the lever to M.

Then turning off the HW doesnt move the lever at all, leaving it at the M position. This also turns off the boiler (The boiler only comes on when HW is turned on).

Turning the Heating off, then returns the lever back to its original position of H. No matter what I try, I cant seem to get the lever to the W position, which means that when I turn the hot water on at the timer, the radiators all heat up. I'm assuming there's some wiring issue or something here or a faulty part? I don't know which part though and I'd very much like to know before I get anyone in to look at this issue.

Hope someone can help me.
Thank you in advance.

 

[seco services]

it's all wrong.
hw on should be in the W position not H.

 

[doitall]

The valve is also upside down which it shouldn't be.

 

[Booie]

So what would you suggest? Get the entire system looked at by someone? An electrian or a plumber?

As for it being upside down, I'm pretty sure that's just the awful angle I had to get my camera in to take the picture =)

 

[seco services]

give us a pic of inside the wiring centre so we can see the wires from the valve.
is a wiring issue.

 

[Booie]

I hope these pictures are good enough (And they help)

 

[mickyg]

thats the valve not the wiring centre! Follow the cable from the valve to where it goes, should hoepfully go to a wiring box. picture of that.

 

[seco services]

wiring centre

 

[DP]

There may be coulple of problems.

Turn power off at the isolator. The lever should restore to W, which is HW zone. This is the position valve will stay at when only HW is heated. Switching of boiler is under sontrol of cylinder thermostat if the timer is active for duration of HW heat demand.

If during this period, Heating kicks in, voltage on white wire will move the valve to midposition with cylinder thermostat maintaining power to boiler.

If HW comes to temperature and cylinderstat switches off or HW timer switches off, voltage on grey wire will drive the valve to H position and orange wires goes live to keep the boiler running.

You want to check if grey wire is live during CH demand only

 

[Booie]

Sorry, my mistake with the last photographs. Plumbing isn't really my strong point, especially when it comes to what each of the parts are called.

I don't have the tools at the moment to test if the Grey wire is live, so hopefully the issue can be spotted from the images below, if not, I'll have to go get some tools to test your theories (DP).

Good luck deciphering this.

 

[seco services]

you'll need your multi meter if you have one.

 

[Booie]

Got my multi meter now. Sorry for the delay, toolbox wasn't at home.

What do I need to test?

 

[seco services]

i would start by checking the ch/hw both off at the programmer

see what v reading you get on the grey - orange - white. terminals.

 

[Booie]

As far as I can tell, there's no voltage on any of those three terminals.

 

[seco services]

do you know what cable comes from your programmer ?


you say your valve sits at H with no call for hw/ch.
you've just tested the grey with no reading.

for the valve to hold in H position you would need power on the grey