Hi,
I'm going to ask some real dumb questions, so forgive me, we have a Baxi 105e with the CH temperature set to approx. 70 degrees, all the radiators have Honeywell 117 TRV's these are all set to the default position '4', with the exception of the 2 lounge rads which are full open as we have a Honeywell CM927 thermostat in this room.
Today I switched the CH in order to run it up for an hour or so in readiness for full running, I had to bleed one of the rads but that's it, what I did notice was that at the bottom of all the rads they were cooler than the top, none were cold and all rads were heating up at the approx the same time.
I set the CM927 to 19 Degrees and left it running , once the room temp was correct I checked the surface temperature of the rads with a digital thermometer and it was between 55 - 60f degrees at the top and then about 10f degrees cooler at the bottom and uniform across the surface of the rads, no rads were cold at the bottom.
Also, I measured the temperature of the feed and the return pipes and the difference was approx. +5 to +1 degrees on the side of the feed pipe.
Does the above sound about right, is it expected that there would be a 10 degree difference, i was expecting a couple of degrees due to convection of warm air and should the reed and feed pipes be similar in temp i thought it was supposed to about a 12 degree difference between the 2 pipes?, would we benefit from getting the system flushed and rebalanced, we've been in the properties 12 years and its never been done whilst we've been here, we did have a Spitotech magnabooster fitted when we first moved in on the advice of the HE who serviced the boiler.
Cheers Jon
I'm going to ask some real dumb questions, so forgive me, we have a Baxi 105e with the CH temperature set to approx. 70 degrees, all the radiators have Honeywell 117 TRV's these are all set to the default position '4', with the exception of the 2 lounge rads which are full open as we have a Honeywell CM927 thermostat in this room.
Today I switched the CH in order to run it up for an hour or so in readiness for full running, I had to bleed one of the rads but that's it, what I did notice was that at the bottom of all the rads they were cooler than the top, none were cold and all rads were heating up at the approx the same time.
I set the CM927 to 19 Degrees and left it running , once the room temp was correct I checked the surface temperature of the rads with a digital thermometer and it was between 55 - 60f degrees at the top and then about 10f degrees cooler at the bottom and uniform across the surface of the rads, no rads were cold at the bottom.
Also, I measured the temperature of the feed and the return pipes and the difference was approx. +5 to +1 degrees on the side of the feed pipe.
Does the above sound about right, is it expected that there would be a 10 degree difference, i was expecting a couple of degrees due to convection of warm air and should the reed and feed pipes be similar in temp i thought it was supposed to about a 12 degree difference between the 2 pipes?, would we benefit from getting the system flushed and rebalanced, we've been in the properties 12 years and its never been done whilst we've been here, we did have a Spitotech magnabooster fitted when we first moved in on the advice of the HE who serviced the boiler.
Cheers Jon
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