Wet UFH Limited by Floor Probe Temp

[mattwaddy]

So my ufh has been working well but has been struggling a litte during this last cold snap. The combi boiler is set at a flow temp of 55*c the manifold is set to supply 45*c and the floor probes act as a limiter with a max floor temp of 27*c. Centers were 150mm sitting on 200mm of celotex.The problem has been that the floor temp keeps getting hit on a regular basis which then restricts the heating and the room temp drop ls quite a bit. So essentially the rooms have struggled to hit the target temp of 20*c. It probably hasn't helped that we've had to remove all loft insulation for a couple of weeks, but I can't quite understand why the floor temp is getting hit so frequently. I'm just wondering if it would be worth dropping the manifold flow temp to 40*c so the floor doesn't hit the floor temp probe max so often? i.e. low and slow build up but hopefully more sustained without interruption.

Any advice appreciated

 

[Mr Chibs]

Could it be heat loss of the room?

If the floor probes are not allowing anything past 27°c, perhaps now that there is insulation missing the room can't maintain your target temperature. Do you have a room thermostat? wondering if you could could disable the floor probes for a day or two.

I haven't got floor probes, and in honesty have no idea what temp the actual floor is, the room is however, pleasantly warm at 19°c.

 

[mattwaddy]

Could it be heat loss of the room?

If the floor probes are not allowing anything past 27°c, perhaps now that there is insulation missing the room can't maintain your target temperature. Do you have a room thermostat? wondering if you could could disable the floor probes for a day or two.

I haven't got floor probes, and in honesty have no idea what temp the actual floor is, the room is however, pleasantly warm at 19°c.

Yes each room has a thermostat, I tried raising the floor probe temp to 30* and that helped. I've replaced all insulation in the loft now, so will see how it fairs.