Search results

Hi again everyone - I’ve had a good look at my sizing now. Alas, I simply do not have wall space for the larger DT30 rads. I can however (just about) accommodate the DT40 sized rads. If I understand correctly, that will give me a flow / return of 70degC / 50degC ? And I’d be just below the...

Thx - I’ll have a read D

Thanks - I don’t mind paying for an app I just couldn’t find one - please send me a link to the one you are referring to Thanks D

Thank you @endecotp - that’s a very valid point. I don’t think my boiler is sophisticated enough to have weather compensation. I guess my only option would be to manually adjust flow temp in summer months. I can 100% see the merit in the recommended DT30. What I’m grappling with is the...

Firstly, thank you for advice and your generosity of time; it’s very much appreciated. There’s still lots I don’t know but I’m much better informed now, than when I started. To recap - - I didn’t get on with on-line heat loss apps - I calculated manually heat loss by room using areas / U...

I’m only altering / repairing an existing system ? Replacing the 40yr old rusty / sludge rads (and trying to get sizing correct). And the boiler and UFH has been installed by a ‘competent person’. The same person will be fitting / flushing / commissioning the rads. D

Sorry, I missed that reply; then figured it out myself 15mins later If I didn’t go the DT30 route; is it just that I’m not taking the opportunity to improve efficiency. And if I size of the DT50 data, it will suffice albeit at perhaps 10% less efficiency. Thanks D

Sorry typo (so 4,5682 4,582W for two but still 620W short of what I’d need).

If I’m calculating correctly………. One of my rooms has two rads set against requirement of 2,668W. My plan was (reading off the DT50 75/65/20 degC Table) 2x 1,400W Type 22; 450(h) x 1,100(w) = 2,800W (I can’t go taller than 450mm). Factored for DT30; the I’d need the equivalent of 5,202W (reading...

Thank you @endecotp…….. The STELRAD data I’m looking at qualifies the T50 with ‘(75/65/20 deg C)’ . So the T50 is the delta of room temp at 20 deg C to the rad temp 70 deg C (being the mean of 75/65 flow & return). if I understand correctly - there is an opportunity here to make the boiler...

Thank you @Notch7 and @Mister Banks for reply. The boiler has (just) been replaced; ecoFIT pure 825 combi; 25 kW / 85,000 BTU. (Old boiler was Potterton 60e 18Kw). New boiler plumbed with two zones: - Z1 17sqm UFH installed and running now. - Z2 x9 rads; flow/return not yet connected -...

Thanks to advice gratefully received, I’ve generated my radiator shopping list (from U values / areas etc and no Apps). I wanted to check against rads that came out (sensible advice from @oldbuffer) that I’m in the right ball-park. I get the feeling the new rads are a tad larger capacity wise...

I’m in process of moving from vented to combi…… I’d like to put a new towel rail in the airing cupboard where the old HW cylinder was removed from. I’m pondering a low wattage electric element for when the boiler is on summer holiday. The alternative (grateful of thoughts); I have a...

Thanks reply. I was concerned that because it has a high thermal mass (big lump masonry), I would need to assume something like a 10 or even 21 deg temp differential. D

I’m working through my rooms; one by one. The internal wall of two rooms is largely made up of fireplace / double chimney breast. I’ve peered in from loft - it’s a single course of bricks with about 300mm of ‘in fill’ in the void between chimney. Would someone be kind enough to suggest a U...

Thank you for the advice…. - I’ve added a 10% weighting for intermittent heating - I’ve assigned different temperatures based on room type - I’ve included heat losses to adjacent internal rooms - I’ve identified solid / cavity walls (from advice on brick bonds) - I’ve dialled back the U value...

Thank you @endecotp - that’s an interesting idea. D

240mm measured at a Window. D

I’ve had a look at my brick bond on older (200mm) walls of house. The oldest part follows the bond pattern you describe: It then transitions to a newer (still old) bond of 2x long bricks followed by a half brick - would this be solid too ? Thanks D

Thank you @oldbuffer - that’s very helpful and generous of your time. As you suggested…… - I’ll add +10% for intermittent heating. - I’ll dial back the U value on the 1957 walls too. - I’ll have a look at the ‘brick bond’ on the older walls to see if I can get a better read out on the...