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Those radiator fans are interesting, I think they would be a good solution to aid me in my rented apartment.
Does anyone have some real world figures if they actually help? And how noisy are they? I am a bit oversensitive to environmental noise.
Yep:
The lower the temperature the bigger the boost. about 60% or so at 35C flow temp.
I can't speak for the ones you buy, as I made my own from PC fans and a PWM speed controller. Mine is audible when sitting next to the rad but it's a lot less noisy than the fridge (it's in the kitchen).
Yep:
The lower the temperature the bigger the boost. about 60% or so at 35C flow temp.
I can't speak for the ones you buy, as I made my own from PC fans and a PWM speed controller. Mine is audible when sitting next to the rad but it's a lot less noisy than the fridge (it's in the kitchen).
Interesting that, so am I right that the room is warmer, but the radiators aren't cooled more by the fans (if they were then it would mean the boiler works harder and costs go up).
Our flow temp. is about 60, maybe 65, even so, as we have an old house ('20's) with no cavity walls it's still bloody hard to heat. We do have double glazing but it's at least 30 years old.
Our boiler is well over specced and the rads are what the engineer recommended - all the same, it takes quite a few hours (maybe 3, dependsing on outdoor temp.) to warm up the rooms, then they cool fast when the heat goes off. I can't bear the idea of keeping the heat on 24/7, which seems to be what heating engineers universally recommend, as SO much just goes straight out the walls.
Anyone got a link to a rad, fan solution that works and one can buy, please?
so am I right that the room is warmer, but the radiators aren't cooled more by the fans (if they were then it would mean the boiler works harder and costs go up).
No - the coooler the radiator is (at the exit) the warmer the room will be, because the heat is being transferred from the rad to the room. There is a temperature drop across the radiator called delta T - Normally at 65C it might be I dunno, 8C, so the input is 65C and the outlet is 57C. If you stick a fan on, the outlet might be 55C which means more heat has been transferred from the rad to the room. The outlet water is cooler, and that mixes in to the outlet water from all the other rads to make the return temperature to the boiler slightly cooler. And the boiler will have to work slightly harder. But, a cooler return temp on a condensing boiler actually improves efficiency anyway slightly. It's exactly the same as having a larger radiator. However, fans do also distribute the air better.
Costs will go up a tiny but but that's because you're putting more heat into the room, so it makes sense.
If your house is poorly insulated (sounds like it is) then you're NOT better off keeping it on all the time. That only works if you have decent insulation.
so am I right that the room is warmer, but the radiators aren't cooled more by the fans (if they were then it would mean the boiler works harder and costs go up).
No - the coooler the radiator is (at the exit) the warmer the room will be, because the heat is being transferred from the rad to the room. There is a temperature drop across the radiator called delta T - Normally at 65C it might be I dunno, 8C, so the input is 65C and the outlet is 57C. If you stick a fan on, the outlet might be 55C which means more heat has been transferred from the rad to the room. The outlet water is cooler, and that mixes in to the outlet water from all the other rads to make the return temperature to the boiler slightly cooler. And the boiler will have to work slightly harder. But, a cooler return temp on a condensing boiler actually improves efficiency anyway slightly. It's exactly the same as having a larger radiator. However, fans do also distribute the air better.
Costs will go up a tiny but but that's because you're putting more heat into the room, so it makes sense.
If your house is poorly insulated (sounds like it is) then you're NOT better off keeping it on all the time. That only works if you have decent insulation.
thanks for the explanation, and the link - looks like it's £107 for each radiator - might be cheaper to just let the rad's come on earlier? Unless we use 'em for years I guess. I can see why you made your own. Then there's the issue of getting the power near to the rads. hmm, looks like I'll have to continue rug on lap and rab hut boots on with a down jacket on top! (this with the room stat set to 20 - and it's maybe reached 18, but not near the floorboards I guess )
Bigger rads ?
Do you have T22 double panel double convector rads installed now? Might be a better bet to increase the btu available from the existing boiler and pipe works. If you can source taller rads that fit I would do that as well. Surprisingly cheap and certainly DIYable .
Maybe do 1 room first to see if you get some gains , will cost more in gas for the initial hour as the hw returns temps will be lower .
Just shut the lock shield valve down on the radiators to get a bigger delta T across the radiator. They should be all balanced anyway with the correct delta T for the heat source.
LOL, mine went on properly a while ago, when it dipped below zero. Now down to -10 and 30 cm of snow out there. Forecast is colder over the weekend
Just shut the lock shield valve down on the radiators to get a bigger delta T across the radiator
That doesn't always work - for whatever reason, the run is too long on mine or the rad is too low down or something. If I throttle down the rads to the appropriate dT/temperature the kitchen one does get warmer but not quite enough.
Do you have T22 double panel double convector rads installed now?
T22s are noticeably thicker and whilst good, don't always fit. However T21s are nearly as good as T22s but barely any thicker than T11 so are a good investment IMO.
Well, won't need the heating this afternoon, just cleared about 30m of path and dug the car out. 40 cm of snow...
thanks for the explanation, and the link - looks like it's £107 for each radiator - might be cheaper to just let the rad's come on earlier?
It can be surprising how much difference changes can make, 5 or 6 years ago I replaced the manual TRV valves on my radiators with "smart" ones, cost me nearly 300 for them and I wondered how long it would take to pay for them, but my next bill was 400 less than the previous few years. Maybe that was a particularly mild winter, but I don't recall it being so.
Of course with the rising costs of energy since they have gone up and last years bill has just come in and is 750 more then that low.
I am also on a communal heating system, all the buildings in the suburb I live in (or at least those built since the 1980's) have to be connected to it, unfortunately it is a bit more expensive than more traditional individual building solutions but is meant to be better environmentally. I was hoping that it might be a bit more insulated from the rising energy cost, as I think they a chunk of the energy comes from burning waste, but that is not proving to be the case.
https://www.entega.ag/geschaeftsfelder/netze/fernwaermenetz/
There is talk of them adding some sort of heat pump to the system, not sure I understand how that would work on such a scale as I believe that the connections from the source to the buildings is high temperatures and that the buildings have some sort of heat exchange instead of boilers.