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The Natural Philosopher
 
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Default Are room thermostats out of fashion?

Christian McArdle wrote:

It's a bit of a fudge, but I can't find a better way of doing it!


Set the TRV to full (preferably replace, so the radiator is lockshield both
ends). Then balance down the hall radiator using the lockshield so that it
warms up slowly and doesn't get very hot. Then, when the other radiators get
shut down via their TRVs, more water gets to the hall radiator. By the time
all TRVs have shut, the hall radiator gets the full force of the boiler,
heats the hall and the room stat shuts down.


I suppose you might argue that that we might as well set the stat to
45C in the evenings and let the TRVs do their job,


This would defeat the boiler interlock and make your system inefficient, as
the boiler will continue to short cycle, heating your primary water which
may lose heat into areas not required to be heated.



(hint. I have done this for some considerable time. The boiler doesn't
short cycle at all. Only in the case of very poorly insulated CH pipes
and a fairly warm set of rooms, and very cold spaces through which the
pipes run [almost impossible to achieve together with fairly warm rooms]
do you get teh '5 minute burn, five minute idle' sort of cycle. You MAY
get this with a fully TRV'ed system with a bypass buit even then its
unlikley. The water has to cool down quiet a lot to overcome boiler stat
hysteresis, and in that time its almost certain that one or more rads
will have opened up the TRV's a tad and be calling for heat anyway. )


Christian.