Old style spur socket

[JohnW2]

There’s no logic though. Double glazing to save heat loss through the window. Then install a fan to extract all your heat. ... Am I missing something?

I don't think you are missing anything. As you imply, there seems to be somewhat of an anomaly resulting from the fact that requirements for insulation ('to keep heat in') sit alongside requirements for rooms to have X number per hour of (heated) 'air changes'.

Unless/until there is heat recovery associated with those X air changes/hour, the whole thing seems essentially daft!

Kind Regards, John

 

[securespark]

The glass suppliers did a good line in cutting the holes for them back then!

A circular line, hopefully.

 

[securespark]

They are not cheap (maybe they are cheaper elsewhere?), but if you are going to change it/ them, then you could get one of these that fits a standard single box.

Flush Clock Connector Square | MK (995WHI)

 

[Bouy]

There’s no logic though. Double glazing to save heat loss through the window. Then install a fan to extract all your heat.

Am I missing something?

Perhaps it to do with trying to keep cooking smells and cooking water vapours contained in the kitchen and extracting direct to the outside, same with wc but without the vapours?

 

[Taylortwocities]

Perhaps it to do with trying to keep cooking smells and cooking water vapours contained in the kitchen and extracting direct to the outside, same with wc but without the vapours?

Yes, I know…it was my attempt at humour!

 

[JohnW2]

Perhaps it to do with trying to keep cooking smells and cooking water vapours contained in the kitchen and extracting direct to the outside, same with wc but without the vapours?

I imagine that nearly all of this understand why people install extractor fans in kitchens, bathrooms and loos. However, that doesn't alter the fact that in addition to sending the smells and water vapour 'direct to the outside', they also send increasingly-expensively-heated air 'direct to the outside' as well.

There are some ways in which the smells and water vapour can be partially addressed without throwing away the 'expensively heated air'. Water vapour can be removed with dehumidifiers (although they use a significant amount of energy). Cooking smells etc. can be parially addressed with things like cooker hoods which have re-circulating fans (i.e. no air sent 'to the outside'), some of the odours etc. being captured in a carbon filter.

Kind Regards, John

 

[JohnW2]

Yes, I know…it was my attempt at humour!

(legitimate) sarcasm, perhaps, but I wouldn't describe it as 'humour' - you were making a very valid point - increasingly valid as the costs of heating air within a house soar skywards!

Kind Regards, John

 

[Harry Bloomfield]

I imagine that nearly all of this understand why people install extractor fans in kitchens, bathrooms and loos. However, that doesn't alter the fact that in addition to sending the smells and water vapour 'direct to the outside', they also send increasingly-expensively-heated air 'direct to the outside' as well.

One call-centre I attended, had heat recovery system on the roof. From what little I investigated, it used a large cast-alloy wheel which rotated, collecting heat from extract air, and transferring it to the incoming air.

At best - I would only expect that to recover 50% of the heat, unless I am failing to understand the principle. Air going out at 22C, air coming in at 12C - it might manage to improve the incoming air to maybe 17C.

 

[ericmark]

I know there were heat recovery units where the heat exchanger was the pipe going through the wall, these cheap units around £300 used just one fan, it relied on a sealed room to push air in other direction, more expensive units the fan both sucked in and blows out.

But as to the clock connection unit, in the main replaced with a fused connection unit, which can also take a 1 amp fuse if you want.

I remember the in window fans, mainly designed to allow air but not flies to pass, and the louvred windows, to allow the heat from the aga to escape, today the induction hob allows heat only into the pan, with very little into the room. I suppose some some troglodytes still use gas, and need fans to extract both the heat and waste gases, however we are considering some automated method to stop the sun over heating home in the summer, automated blinds are far cheaper than an AC.

 

[Harry Bloomfield]

(legitimate) sarcasm, perhaps, but I wouldn't describe it as 'humour' - you were making a very valid point - increasingly valid as the costs of heating air within a house soar skywards!

The alternative doesn't bare thinking about, of our homes filled with lots of moisture, damp and mould. Restricting extraction, to close to sources needing to be extracted is quite an efficient process in practice.

Water vapour can be removed with dehumidifiers (although they use a significant amount of energy).

I wouldn't describe a dehumidifier's consumption as 'significant'. They are significantly cheaper to operate, that the alternative process of extracting the moist air.

As I have reported before, I run a portable dehumidifier plus a fan, as a much cheaper alternative to using a drier machine.

 

[JohnW2]

One call-centre I attended, had heat recovery system on the roof. From what little I investigated, it used a large cast-alloy wheel which rotated, collecting heat from extract air, and transferring it to the incoming air.

Indeed. As I wrote earlier ...

Unless/until there is heat recovery associated with those X air changes/hour, the whole thing seems essentially daft!

At best - I would only expect that to recover 50% of the heat, unless I am failing to understand the principle. Air going out at 22C, air coming in at 12C - it might manage to improve the incoming air to maybe 17C.

Yes, if it's done just with a ('passive') 'heat exchanger', then I think your physics and maths are correct. If air enters and leaves the building at the same rate, then the very best a heat exchanger could do would be to raise the temp of incoming air to the average of outgoing and incoming temps - e.g. from 17° to 19.5° with your figures.

However, there are obviously much more effective methods of heat transfer which can work against large temp gradients - a.k.a. 'heat pumps'/aircon. However, the energy efficiency of such methods is limited by the fact that the kit to do it itself consumes an appreciable amount of energy (although I suppose some of that can also be 're-captured' as 'usable heat').

Kind Regards, John

 

[ericmark]

It seems odd, last house my weather station was reporting around the 70 - 80% humidity, this house today is showing 52% as to why not a clue, as to air conditioning never bothered in last house, but this house has windows which seem to catch the sun. So have an AC exhausting though the chimney, the biggest problem is the amount of water it extracts, and having to empty the bottles of water.

To keep the home cool, in summer I will get up at 5 am and open the patio doors and up stairs windows and allow the house to cool, but as the day progresses the doors and windows need closing to stop heat entering the house.

Some automated device which can work out when to exchange air and when not to would really cut down on cost of running an AC. This will likely need power near windows, but as yet still not found a way to do it.

Odd but years ago we had auto openers for green house windows, but not in the home.

 

[JohnW2]

The alternative doesn't bare thinking about, of our homes filled with lots of moisture, damp and mould.

I'm not convinced that it's as big an issue as you imply - after all, we managed for centuries/millennia, without extractor fans. We very rarely (need to) use the extractor in our kitchen

Restricting extraction, to close to sources needing to be extracted is quite an efficient process in practice.

If one has a decent flow rate, extraction will not be restricted to a small area. If one goes with guideline 'air changes per hour', lots of air will be pulled in from other parts of the house (and ultimately from 'outside) to replace the extracted air, no matter how close the extractor is to the cause of the the moist/malodourous air.

I wouldn't describe a dehumidifier's consumption as 'significant'. They are significantly cheaper to operate, that the alternative process of extracting the moist air.

If extraction of air is the alternative, then a dehumidifier will, indeed be a cheaper option. Maybe they have got a lot better (less energy hungry) but I used to run dehumidifiers continuously during Winter in a a couple of large but rarely heated rooms. However, I stopped doing that routinely when I discovered that, between them the two dehumidifiers were accounting for more than 10% of my total electricity consumption.

Kind Regards, John

 

[EFLImpudence]

As it says in the Building Regulations, dwellings must be adequately ventilated.

This can be achieved either naturally or in the case of modern sealed properties with fans.


I cannot stand the sound of fans so have never used them and have never had any trouble with condensation, mould or excessive smells.

Open a window or two to create air flow. Yes, I know it's cold outside but you can't have everything.

 

[JohnW2]

It seems odd, last house my weather station was reporting around the 70 - 80% humidity, this house today is showing 52% as to why not a clue, ...

I've never really understood indoor humidity levels. In the UK, outside humidity is generally 50%-100%, but everywhere inside my house is usually 50-70%, even when outdoor humidity is very high. Interesting, during the recent very hot spells, the indoor figure hear dropped to 25-30%

Some automated device which can work out when to exchange air and when not to would really cut down on cost of running an AC.

I'm not sure that I fully understand what you are suggesting

Kind Regards, John