I'm just sizing a radiator for my son's bedroom. The room is about 1000 (13 x 10 x
cu feet, one external wall, which faces south-east (i.e. very good for sun). At the moment the loft insulation is poor, and it is single glazed. Both of these will be changed in the next year or so.
The central heating system is a wet system, with a new Vaillant combi boiler.
2 questions:
1. I've looked at various online calculators for working out the radiator size in Btus. The results vary widely between about 1500 and 5000. What gives?
2. We're concerned about GCC, energy consumption and cost. So we're quite prepared for the radiator to be slightly 'underpowered'. If this means that on the very coldest of days the room is a bit chilly that's no problem. I intend to insulate the loft as heavily as I can, and when the time comes to fit a new window (which is about 2 sq metres, by the way) it'll be double (maybe even triple) glazed, with reflective glass, argon filled if I can get it etc.
I've read somewhere that a slightly underpowered radiator which is on all the time is better than an overpowered one which is constantly turning on and off (with the TRV).
I also read somewhere that condensing boilers may or may not work best at 'full stretch' but it wasn't clear what the poster meant
Your opinions please.
cu feet, one external wall, which faces south-east (i.e. very good for sun). At the moment the loft insulation is poor, and it is single glazed. Both of these will be changed in the next year or so.The central heating system is a wet system, with a new Vaillant combi boiler.
2 questions:
1. I've looked at various online calculators for working out the radiator size in Btus. The results vary widely between about 1500 and 5000. What gives?
2. We're concerned about GCC, energy consumption and cost. So we're quite prepared for the radiator to be slightly 'underpowered'. If this means that on the very coldest of days the room is a bit chilly that's no problem. I intend to insulate the loft as heavily as I can, and when the time comes to fit a new window (which is about 2 sq metres, by the way) it'll be double (maybe even triple) glazed, with reflective glass, argon filled if I can get it etc.
I've read somewhere that a slightly underpowered radiator which is on all the time is better than an overpowered one which is constantly turning on and off (with the TRV).
I also read somewhere that condensing boilers may or may not work best at 'full stretch' but it wasn't clear what the poster meant
Your opinions please.
