Checking the mechanics of a motorised diverter valve

[AOSB]

I have a problem with my heating system. I discovered the powerhead of a 3 port diverter was not working properly and the microswitch was not being operated postively as the valve turned. so sometimes the boiler had no heat demand signal and sometimes it got the signal after a very long wait. I have replaced the powerhead but I am worried that when the head was off I could only turn the valve through about 60 degrees and that worried me that doesn't seem to be much movement. Its a Honeywell body by the way. I cant find a drawing that shows what the angular movement should be - any one know please?

Also I am puzzled because this single zone gas CH/HW system has two MV's; a 2 port in the HW heat exchanger feed AND a Diverter (Not Mid) 3 port MV. This does not seem to me to be one of the usual Sundial plans. Again any help would be appreciated.

 

[D_Hailsham]

I could only turn the valve through about 60 degrees

That's nothing to worry about. Honeywell say that the valve spindle only moves about 20 degrees

Also I am puzzled because this single zone gas CH/HW system has two MV's; a 2 port in the HW heat exchanger feed AND a Diverter (Not Mid) 3 port MV. This does not seem to me to be one of the usual Sundial plans.

Sounds as if someone converted a W-Plan to a sort of S-Plan.

Is the 2 port valve fed from the HW port of the diverter valve?
Is the 2-port valve controlled by a cylinder thermostat and does the valve control the boiler?
Does the diverter valve normally have the HW port open and the CH port only opens when power is applied to the valve motor?

 

[gavinda]

Also I am puzzled because this single zone gas CH/HW system has two MV's; a 2 port in the HW heat exchanger feed AND a Diverter (Not Mid) 3 port MV. This does not seem to me to be one of the usual Sundial plans. Again any help would be appreciated.

its an unvented cylinder .