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No call for flame after replacing Grasslin 2 port actuator

Postby T00true » Sat Jan 30, 2021 6:35 pm

I am using a Hive multi zone system with 2 thermostats (one for upstairs radiator and one for downstairs underfoot heating)
The downstairs heating was not coming on so I had a look at the Grasslin 2 port actuator and it appeared the motor had gone. I replaced the actuator which now works. It opens the valve which turns on the boiler pump but there is no call for flame. The other thermostat works fine and both are wired up identically. The downstairs will only heat up if the upstairs is calling for flame. Any ideas.
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Simply Build It

Postby ericmark » Sun Feb 07, 2021 3:49 pm

Orange wire from motorised valve should both start pump and boiler, but with multi pumps you need some form of relay, some times part of a control centre.
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