Possible faulty mid position valve?

[Jamie10]

Possibly faulty mid position valve?

Hi everyone

As the summer is here I decided to turn my central heating off but keep the programmer on for the hot water.

However, even though the programmer shows the CH as off the radiators still get hot! in line with the Water program

Could this be a faulty diverter valve. I have a mid position drayton MA1 fitted. How can I tell if this is working correctly? Do I need to drain the system down?

Any help would be much appreciated!

Thanks
Jamie

 

[alkalinepantera]

Sure does. you can tell by actually removing the powerhead on top of the divertor valve. this will give you an indication if the powerhead has gone, siezed or the valve body itself has siezed. if its a midposition actuator(three connections) then the valve spindle should be in rest mode for hot water only. You can tell this by looking at the straight edge of the divertor spindle. this should be inline with the body. if this is the case the divertor body requires replacing as it is passing. If it is on a 45' angle then the valve has siezed open to mid position(hw and heating). Usually the short term solution for this problem is manually turning it back to hw only(see above). hope this helps.

 

[ChrisR]

That valve has an indicator on the side. Does it go back to HW position or stick in the middle (M)?

 

[Jamie10]

Thanks for the replies.

Right here goes.

The spindle/indicator is in the middle position (M). When I test for movement i.e CH, CH&HW and HW there is no movement or noise from the unit/head. This obviously explains why the rads heat up coming on when the HW kicks.

When I take the head/unit off and test the indicator on the unit, it does move to its relevant positions. Although when CH & HW turned off it remains at its last program.

The spindle on the joint itself is very stiff. Should it be so stiff?

Is it possible that the head is just not powerful enough to turn the spindle.

Or am I just hoping as the other option would be to drain the system and replace the valve which sounds like alot more work!

Jamie

 

[Jamie10]

Whoops sorry should mention that one of the plastic points on the bottom of the unit has snapped off and fell down its relevant hole. Not sure if I did this or if it was already like it?

 

[Jamie10]

Any ideas on the above?

I am thinking of replacing the valve and head. How hard is it to drain the system? I think its a Y plan set up. Boiler, Tank, Pump, mid position valve and programmer.

Jamie.