Worcester FW100

2 Mar 2013
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United Kingdom
Hi, Has anyone fitted the Worcester FW100 controller who can help me please.

I have one fitted with all default settings except for the UK min temp which is set to -3 as advised by Worcester technical support.

I have the comfort setting to 19c and economy to 15c.

The outside sensor is fitted correctly and registers the correct outside temp.

What I do not understand is why the FW100 mounted in the hall shows a room temp of 21-22 but yet the burner and pump intermittently goes on and off. I would have thought it the boiler would stay off until the room temp reached the comfort temp set ?

This also happens at night when the FW100 switches to economy after 10pm, I can hear the boiler going on and off throughout the night even though the FW100 in the hall shows the room temp of a higher temp.

it seems the heating temp (comfort and economy) is somehow not linked to the room temp showing on the FW100....

Please help... am I got a faulty controller or is it i have not understood the relationship between the heating parameter of comfort and economy and the showing room temp on the controller :(
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Hi Peter,

The boiler is a Worcester 42CDI installed in the loft and the FW100 mounted on wall downstairs in the hall away from sunlight etc.
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I am trying to understand the relationship between the Comfort Set Temp of 19 degrees and the displayed Room Temperature on the FW100

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