Sticking mid-position valve

[echoes]

I have a Horstmann Y-plan valve which does not return to the 'hot water only' position from the mid position. ie. when both HW and CH are 'on' at the timer, but the room stat becomes satisifed.

If I wiggle the lever on the valve it does go back to the correct position, but won't go under the power of its own spring left to its own devices.

Does anyone have any tips for fixing this? (apart from avoiding Horstmann products in future - I had a room stat of theirs and that was c**p as well).

 

[Bahco]

See if This helps.

 

[BobbyBreakit]

I have a Horstmann Y-plan valve which does not return to the 'hot water only' position from the mid position. ie. when both HW and CH are 'on' at the timer, but the room stat becomes satisifed.

If I wiggle the lever on the valve it does go back to the correct position, but won't go under the power of its own spring left to its own devices.

Does anyone have any tips for fixing this? (apart from avoiding Horstmann products in future - I had a room stat of theirs and that was c**p as well).

I have the same problem, I even bought another one and it does the same..
You can even turn the power off to the whole system and it still stays mid position. This happens even if the motor is taken off the valve

 

[seco services]

maybe the valve is sticking due to crud in the system or semi seizing.