Ultracom 30 cxi doesn't reach set temperature it gets close and just hovers around it it's been on for 2 hours now and hasn't switched off it is constantly burning gas I've tried balancing the system but then it short cycles it's a 2 year old system and has only started doing this since I changed a radiator from a single to a double and is not a very big system only 7 radiators any help will be gratefully apriciated
Glowworm ultracom doesn't reach set temp
- Thread starter Billybob201206
- Start date
Its set at 65 and is hovering at 65 but even if its set to *ny other temp it still does the same if you turn the temp down by 2 degrees when its at 65 to 63 it stops burning then but if you leave it it will not turn off it has to overshoot the set temp by 2 degrees before it turns of but because it modulates down it cannot reach the temp to turn off if this makes sense
Will adjusting the bypass valve make any differense as it seems like the water in the system flows to fast so it doesn't heat it enough and pumps it through the rads
Will adjusting the bypass valve make any differense as it seems like the water in the system flows to fast so it doesn't heat it enough and pumps it through the rads
Had another play tonight tried balancing again reducing pump speed changed to different temperatures the only thing I found that makes it switch off was turning the biggest radiator off in the living room tried range rating it to 14kw didn't work the total btus of the rads is 36000 the boiler is 30kw and reckons it can handle 100000btus so I can't see it being under powered it's always been set to 20 kw before and worked fine until I changed a single rad for a double is there any settings to adjust the modulation as when it's set to 82 degrees it gets there really easy but then when it modulates down it can't gain enough of a trickle to actually turn off
Would adjusting the internal bypass of the boiler affect this in any way ie sending slightly walmer water through the bypass rather than back to the boiler any help is appreciated thank
Would adjusting the internal bypass of the boiler affect this in any way ie sending slightly walmer water through the bypass rather than back to the boiler any help is appreciated thank
I don't want it to turn off I want the boiler to reach the set flow temp and then cycle like it should do not constantly burn gas for 2 hours
It sounds to me like the boiler is working as it should be!
Prior to adding the additional radiator capacity, you imply the boiler was cycling!? This was likely due to not enough heat being dispersed in your system compared to how much heat was being generated by your boiler. Now you have added ability to disperse more heat (bigger rad), the boiler is maintaining it's flow temp by modulating it's burner without the need to cycle.
Do you have a room thermostat? (I'm guessing you haven't and think this is where the issue actually is!) Adding a boiler interlock (room thermostat) will stop the boiler overheating your property by cycling at the set temperature or modulating the flow temp and is now a requirement on all new installations.
Yes I have a didpgital roomstat that's set to 21 degrees thankfully
So your saying if I wanted to run my heating 12 hours a day and didn't have a roomstat the boiler would be burning gas perminantly for 12 hours that seems a bit unlikely to me what's the point of the boiler having an in built thermostat if this is the case
If the boiler is ste to 57 degrees it should reach 57 degrees then the burner turn off completely and the pump disperse the heat through the system otherwise it would cost a fortune to use it
So your saying if I wanted to run my heating 12 hours a day and didn't have a roomstat the boiler would be burning gas perminantly for 12 hours that seems a bit unlikely to me what's the point of the boiler having an in built thermostat if this is the case
If the boiler is ste to 57 degrees it should reach 57 degrees then the burner turn off completely and the pump disperse the heat through the system otherwise it would cost a fortune to use it
It should NOT turn off !
Its more clever thatn that.
It modulates down to provide enough heat to match the heat loss of the property!
Its fine!
Tony
As per Tony's post
It is a MODULATING BOILER
it is supposed to maintain the temperature to around or just below the "set point" (the temperature selected by you) it reduces the gas rate to a point where the boiler & system is in perfect balance
Combustion Engineers have proved that a burner that cylces on off on off etc will use far more fuel than a modulating burner that runs constantly
REASON- when a burner switches off, the heat exchanger becomes a heat emitter, and all that heat goes??? yep out of the flue!!
It is a MODULATING BOILER
it is supposed to maintain the temperature to around or just below the "set point" (the temperature selected by you) it reduces the gas rate to a point where the boiler & system is in perfect balance
Combustion Engineers have proved that a burner that cylces on off on off etc will use far more fuel than a modulating burner that runs constantly
REASON- when a burner switches off, the heat exchanger becomes a heat emitter, and all that heat goes??? yep out of the flue!!
I decided as you guys say its running as it should I will leave the locksheild valves fully open as the system heats up evenly like this anyway I set the thermostatic valves to an acceptable level (3) and to let the roomstat controll the overall temp of the house it just seemed to me that the boiler not cycling seems such a waste of money ie because its always burning but you guys know better than me so thanks
And just for the sake of checking I've bought some clamp on thermometers just to see if I can balance it to get 11 degrees on each rad and try it like that for a few days just to see what the difference is
And just for the sake of checking I've bought some clamp on thermometers just to see if I can balance it to get 11 degrees on each rad and try it like that for a few days just to see what the difference is
Combustion Engineers have proved that a burner that cylces on off on off etc will use far more fuel than a modulating burner that runs constantly
REASON- when a burner switches off, the heat exchanger becomes a heat emitter, and all that heat goes??? yep out of the flue!![/quote]
to repeat a constantly burning appliance matched to system load is more efficient than an on/off type appliance FACT!
REASON- when a burner switches off, the heat exchanger becomes a heat emitter, and all that heat goes??? yep out of the flue!!
[/quote]to repeat a constantly burning appliance matched to system load is more efficient than an on/off type appliance FACT!
As it is at the moment with the locksheilds fully open it gets a differential of up to 17 degrees on initial heat up from cold but as it modulates and reaches near the set temp it goes down to about 7 degrees diferential so I though maybe if the water flow is restricted slightly it would be a higher diff and as a result be condensing more and be more efficiant
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