Now that I've got my smart thermostat in operation if can see from the app the loungw temperature and the external temperature.
For the past 4hrs the outside temp has gone from 10decC to 9degC whereas the lounge temperature has dropped from 20degC to 19.5degC.
The heating, set for 19degC, has obviously not kicked in yet.
Can I deduce anything meaningful about the heat losses in the lounge? The rest of the house will not be dissimilar.
No, air temp is mostly controlled by masonry temp, which is controlled very slowly by air temp. So it tells you jack.
Probably not much you can deduce in a hurry from just a small set of temperature data - there are too many variables, and the response of the building might need to be measured in days not hours.
You could make an analytical stab at heat loss calcs:
Looks excellent - but for some reason the Excel file isn't downloading - just redirects to the front page.
I was thinking of doing a basic 'heat loss audit' with a thermal camera (MLX90640 I've yet to build). I was put in touch with a local university bod who basically told me not to bother as it requires a properly calibrated camera, and full knowledge of the variables with measurements taken over long and properly defined periods. Do you have a view?!
Might have been a casualty from when the
I can't see the spreadsheet anywhere in the file list page, maybe John's got an offline copy somewhere?
Yes also localisation is a thing. I still get more loss through a double glazed window than a non cavity wall here. This can set up a draught of course. I'm sure new window designs and some wall treatment might help but in rooms where things are screwed to walls and window replacement would make one heck of a mess..... Brian
Yup the links were pointing at the old www. site.
I have changed the list of allowed document types on the wiki to now include Excel, Word, and Powerpointless (in their original and .???x versions) - so you can now upload those file types in addition to the normal image file formats and PDFs.
I have uploaded the sheets and fixed the links in this article as well.
(I will do another post about the new upload formats for others not reading this thread)
Of course... I think Geoff was also taking a weekly backup of the content of the site.
There is a PDF grab of the whole FAQ site as of Jan this year when it was retired:
No. You might be able to when the outside temperature is -10C and you are prepared to turn all heating off inside and see how slowly the temperature falls over say 5 degrees from a nominal start of 20C.
And then how quickly the heating on full bore can bring it back up to
20C once it has fallen to 15C. You want a huge temperature difference with the outside temperature, a still day and no external doors opened during the test.I calibrated the VH electric heaters that way so that we could estimate the right time to turn them on ready for a hire. No point in heating an empty building (beyond frost stat levels) with electricity so expensive!
Works a trreat now, thanks very much.
You could just use a optimising stat - they learn the building characteristics, and turn the heating on in advance. So if you program it to say I want it at 20 from 6pm, it will look at the history, and the current temp, and may decide that means heating on at 4pm to hit the target by 6.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.