Heatline C28 diverter valve motor test

2 Jun 2009
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United Kingdom
Hi, I,I am having hot water problem on C28 boiler. A new plate heat exchanger, valve and diverter motor was installed recently and the boiler was working fine. However now after few days, I am not getting hot water, it is a bit warm but the pipe going to radiators is burning hot. I guess the valve spindle is not being pushed correctly? I have removed the actuator motor and do not see it doing anything regardless of whether there is a demand for hot water or central heating.

My question is that if I removed the actuator motor from the valve and then demanded hot water, should I see the little spindle inside the actuator motor come out? I am not seeing the spindle move at all whether I demand hot water or central heating. Is there a way to test the actuator motor directly with ac mains supply. The connectivity between the motor and pcb seems fine (all 3 wires). Any help would be really appreciated. Thanks
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That is what is expected.

First you need to measure the voltage applied to the motor in each boiler mode. 230 vac

You can test the motor by applying neutral to centre tag and live to each of the other tags in turn.

It should motor to each position and then disconnect the motor from the supply.

Who replaced all those parts?


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