Honeywell 3-way valve defective?

[ron56]

thanks agile..this morning I switched on HW "all day" for about 30 minutes ..no hw to the cylinder but the rads got nice and hot!..nice cos it's cool today. So the "ball" is presumably stuck across and blocking the HW port of the valve...it seems to be making a perfect seal!..As I said moving the lever to manual has no effect..moving the lever does nothing..it's "floppy"/no resistance/no spring felt

 

[Agile]

It may well be that the shaft is seized or the gears jammed.

As long as there is a dimple on the case you can remove the head and inspect it.

Tony

 

[Steelmasons]

Gears jammed?..never.

 

[dilalio]

The teeth get worn on the armature or filled with gunk and the springs cause it to slip on the drive cog - I dismantled a buggered one the other day to show my son how it all works - don't think he was overly impressed as it didn't have a processor or 4K video card