Motorised valve replacement

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Hi, I'm new on here and just looking some advice. We occasionally stay in a relative's apartment. The gas boiler fires up and twenty minutes later the radiators are still stone cold. In the hot cupboard a pipe is roasting below a motorised valve and lukewarm above it. I moved the lever to manual and the radiators warmed up. The rest of the week the heating worked fine. Over the last few years this seems to be the way it goes. I suspect the valve underneath the actuator is sticking and the actuator is unable to open it automatically and a few manual turns with the lever frees it up.
My question is: Can the actuator be removed and the valve freed up manually or does the entire system need to be drained and a new motorised valve installed? Thanks.
 
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What flavour valve is it? 2 port (1 pipe in, 1 pipe out) or 3 port? Brand? (Honeywell, Drayton).
One other question to be asking- usually with motorised valves the microwitch in the valve is what tells the boiler to fire- the timeclock and room stat just open the valve when heat is required.
Back on point- yes the actuator mech is usually easily removed, if the valve turns easily with a set of pliers likely the motor has got tired, can be replaced easily enough without removing the valve.
 
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Thanks for the replies. I thought I had a photo but I can't find it. I'm 99% sure its a Danfoss 2 port valve ( White plastic head unit with chrome lever). The white head unit also gets quite warm until I manually open the valve using the lever. Then it cools and the radiators warm up. Cheers
 
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danfoss are prone to very tiny weeps on spindle that if left long enough could stop spindle moving initially so case of live with it or change to another make of valve
 
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What flavour valve is it? 2 port (1 pipe in, 1 pipe out) or 3 port? Brand? (Honeywell, Drayton).
One other question to be asking- usually with motorised valves the microwitch in the valve is what tells the boiler to fire- the timeclock and room stat just open the valve when heat is required.
Back on point- yes the actuator mech is usually easily removed, if the valve turns easily with a set of pliers likely the motor has got tired, can be replaced easily enough without removing the valve.

The motors tend to work, or not work. The actual mechanism driven by the motor is what tends to become tired and jam, due to the extreme force they are under from the return spring.

If once the head is removed, the valve can be rotated with just slightly more than bare finger pressure (pliers), then fit a new complete head/actuator.
 
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Extreme force ? from a spring a bit bigger than is in a biro

Think again, you have obviously never seen inside a valve actuator. They contain an extremely strong hair spring - they need to be strong, to both turn the valve and the unpowered motor/gearbox in reverse.
 
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Think again, you have obviously never seen inside a valve actuator. They contain an extremely strong hair spring - they need to be strong, to both turn the valve and the unpowered motor/gearbox in reverse.
pmsl seen in more valves than you have had hot dinners extremely strong spring my ar5e its a weak little spring
 
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IMG_20211229_214030.jpg
that big powerful spring in relation to a bleed key. (n)
 
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pmsl seen in more valves than you have had hot dinners extremely strong spring my ar5e its a weak little spring

Nice try, but entirely the wrong type of spring. If I can be ar5ed, tomorrow I might get around to posting a photo of an actual spring.
 
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And there is a pic of the two in situ in a Drayton valve with the second picture showing how much smaller still the Drayton spring is to the honeywell on
IMG_20211229_220514.jpg
IMG_20211229_220608.jpg
 
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It's the syncro motor which dies in the head, isn't it?

Every thing else is passive.

You can buy a new motor for a lot less than a head iianm.
 
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It's the syncro motor which dies in the head, isn't it?

Every thing else is passive.

You can buy a new motor for a lot less than a head iianm.
no the teeth on rack wear out or break, the microswitches can stick the plastic leavers can snap . there is several things that can go up with a head other than just the motor
 
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