Mid-position valve problem
 

Hi

I've been having problems with the central heating where the rads are
coming on when the boiler is intended to be only heating the water. I
immediately assumed there was something wrong with the mid-position
valve.

It is a drayton MA1, where the actuator push-fits onto the valve
assemble.

Examination of the actuator revealed rattling parts inside and opening
it up I have discovered that the plastic nodule holding one of the
return springs has broken, so clearly there was not enough force for
the mid-position valve to be brought back to the HW only position.

Ordered a new actuator which arrived at the weekend.

I pushed it into place a wired exactly as it was before, but this
doesnt seem to be working at all - always seems stuck in mid-position.

Does anyone know anything about these MA1 actuators? There is a black
button at the end of the assembly which sticks out on the old (broken)
actuator, but is pushed in on the new one. Does this have to be
released in order for the actuator to run freely between its three
positions? I gently tried to turn the actuator by using a screwdriver
in the valve hole, but it is stuck.

thanks
Nigel

In article .com,
writes:
Hi

I've been having problems with the central heating where the rads are
coming on when the boiler is intended to be only heating the water. I
immediately assumed there was something wrong with the mid-position
valve.

It is a drayton MA1, where the actuator push-fits onto the valve
assemble.

Examination of the actuator revealed rattling parts inside and opening
it up I have discovered that the plastic nodule holding one of the
return springs has broken, so clearly there was not enough force for
the mid-position valve to be brought back to the HW only position.

Ordered a new actuator which arrived at the weekend.

I pushed it into place a wired exactly as it was before, but this
doesnt seem to be working at all - always seems stuck in mid-position.

Does anyone know anything about these MA1 actuators? There is a black
button at the end of the assembly which sticks out on the old (broken)
actuator, but is pushed in on the new one. Does this have to be
released in order for the actuator to run freely between its three
positions? I gently tried to turn the actuator by using a screwdriver
in the valve hole, but it is stuck.

I don't know that model, but they normally have a way to lock
the valve in mid-position so you can drain down the system
when it's not powered.

--
Andrew Gabriel

In an earlier contribution to this discussion,
wrote:


Does anyone know anything about these MA1 actuators? There is a black
button at the end of the assembly which sticks out on the old (broken)
actuator, but is pushed in on the new one. Does this have to be
released in order for the actuator to run freely between its three
positions? I gently tried to turn the actuator by using a screwdriver
in the valve hole, but it is stuck.

I don't know this particular model - but didn't it come with any paperwork
explaining it's operation?
--
Cheers,
Set Square
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Hi

I've been having problems with the central heating where the rads are
coming on when the boiler is intended to be only heating the water. I
immediately assumed there was something wrong with the mid-position
valve.

It is a drayton MA1, where the actuator push-fits onto the valve
assemble.

Examination of the actuator revealed rattling parts inside and opening
it up I have discovered that the plastic nodule holding one of the
return springs has broken, so clearly there was not enough force for
the mid-position valve to be brought back to the HW only position.

Ordered a new actuator which arrived at the weekend.

I pushed it into place a wired exactly as it was before, but this
doesnt seem to be working at all - always seems stuck in mid-position.

Does anyone know anything about these MA1 actuators? There is a black
button at the end of the assembly which sticks out on the old (broken)
actuator, but is pushed in on the new one. Does this have to be
released in order for the actuator to run freely between its three
positions? I gently tried to turn the actuator by using a screwdriver
in the valve hole, but it is stuck.

thanks
Nigel

These actuator heads all have a manual operating lever on them, which is
used to flood system before full activation of all the equipment. The black
button on the side of your one is the manual lever. Have you tried moving
the valve itself? It may be the valve that is stuck, and this burnt out the
original actuator head. Place a spanner on the valve and move it. If it is
too difficult for you to move manually, then the actuator head is really
going to struggle.

Don't just blame the electrics. :-)

Thanks! I have just released the button and all is working. I should
have done that at the start, but it was stiff and I didnt want to break
it.

They are obviously shipped that way as most installations will be first
time where the mid-position needs to be held in order to fill the
system.

Wonder how long it will be before it needs another replacement :(