New oil to gas install. Bottom of rads cold.
- Thread starter fitzykev
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My radiators will also take a long time to heat, it depends on the lock shield valve setting, and the TRV heads, and how long the boiler runs for. My thermostats are set to oil, so depending on the thermostat used it may need setting to gas now, but this should have all been done by the installer. Seems he has only done half a job.
Its a worchester bosch greenstar 4000 and it came with the bosch easy control thermostat so its the correct thermostat. The app seema to be running fine and i have set my scedules and its kicking in when it should
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Late mother house (here still using non modulating oil boiler) the radiators may get hot first thing in the morning when re-heating the room, but most of the time, the radiators were just warm, whole idea is not to turn boiler on/off/on etc, but for it to modulate i.e. turn down the output, and each TRV should regulate the output so it just maintains the room.
I did note, today the wife's bedroom TRV had kicked the boiler in, I also note, the Bosch easy control does use smart TRV heads,
so each room is independent. I would guess it works similar to my Drayton Wiser system. So the app should show something like this 
so if the room is keeping reasonably close to the setting programmed into the thermostat be it wall mounted or on radiator, then no worries. Hardly matters if top, bottom, left or right side gets warm, as long as it heats the room. I often find radiator is not hot all over, and mine is an on/off boiler, mothers house, the radiators only got warm, that is what they should do to avoid hysteresis.
I did note, today the wife's bedroom TRV had kicked the boiler in, I also note, the Bosch easy control does use smart TRV heads,
so if the room is keeping reasonably close to the setting programmed into the thermostat be it wall mounted or on radiator, then no worries. Hardly matters if top, bottom, left or right side gets warm, as long as it heats the room. I often find radiator is not hot all over, and mine is an on/off boiler, mothers house, the radiators only got warm, that is what they should do to avoid hysteresis.
The weather is warmish, the house is warmish - so there is less demand for heat from the boiler. What water the boiler does need to heat, will accumulate at the upper part of the radiators. Have you tried, setting the room thermostat, and the TRV's, to maximum?
Is your house adequately warm? If not, might the lower part of the radiators be blocked up with sediment?
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Do you mean the previous boiler didn't have that problem? Maybe increasing the pump speed would help, if it's an option on that boiler
Press and hold the ok button on the boiler display panel then put the boiler into chimney sweep mode. The boiler should now run for 10 minutes at full rate. If your radiators are fully heating then you might have an issue with your new controller or it might be set up for load compensation. If the radiators don’t heat fully then you have a circulation problem. If the issue is the latter, try turning off all the radiators and see if they’ll heat individually or call back the installer
I’ve seen a chimney sweep mode on my Vaillant EcoTEC plus 418. What does the chimney sweep mode actually do? Does it give the boiler/burners a good clear out or is it for something else?
It’s to check the CO/CO2 combustion is within the range required for the appliance. It’s normally done at a maximum and minimum setting. Cleaning the heat exchanger requires a bit of elbow grease
Maybe in my circumstances the boiler is taking into consideration the outside temp and the internal temp and is not firing fully to bring the heat up as its worked out that it does not need to fire fully to get to my desired temp
That is the sensible answer. Mine has a similar, fancy control system fitted, and I often find that just the upper part of the radiators are warm.
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