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the port motor is probably stuck. powering down electrics watching that small leaver on the box will reveal whats happening. it can also be slid and locked over to make the flow manualy. easy to change the box only though if your competant with basic electrics
if box feels quite wrm then motors jammed, it might free off powering off supply.
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Ryse wrote:
December 7th, 2019, 2:07 pm
I tried moving the lever manually but nothing wrks could I need a new 2 port valve
i would change it after trying what i said first.
power off-remove little screw on side casing to reveal two screws inside box fixing controler to brass valve.
you can either get the honeywell replacement for about £60-70 or a copy part (the metal ones are all honeywell compatible)
the rest is swap the wiring in the white box like for like the re-attatch motor head to valve.
By joni os
When changing motorized valves best to match with existing because nuts and threads differ between makes and removal of olives to change nuts can cause problem especially if old 3/4"pipes are present. Tracing cable back to junction box, grey wire should be permanent energized. brown wire energized on call for heat and when valve fully open orange wire also becomes live. The orange wire becomes live through contact in valve but sometimes wear in valve prevents contact and then boiler will not fire, Checking this sequence on replacement head will confirm everything OK.

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