Venting hot air into loft

Jezzar · 20-05-2010, 10:34

Wondering if anyone has done this? I have a growing number of sky boxes, computers etc, and the whole room is an oven. I'm planning to put them in the cupboard, and as it's upstairs, cut a hole in the ceiling and put a 12cm case fan in it to help push the heat upwards into the loft space.

Has anyone tried anything similar? Any thoughts appreciated!

njp · 20-05-2010, 10:40

My thoughts are that in summer, your loft space probably gets very hot indeed, and that trying to use it as a dump for hot air from below probably won't be very effective. And that by placing all your power-hungry devices in one small space, you will make the cooling requirement more critical, and increase the risk of hardware failure.

Jezzar · 20-05-2010, 10:59

You may have a point there njp. The heat's taking over the top floor at the moment though, and kept us awake last night so am running out of options.

Anyone got a better solution?

njp · 20-05-2010, 11:09

How much power are we talking about here? The weather hasn't even started to get hot yet, so I fear for your future!

Does everything have to be left on at all times? Could you manage the energy consumption, rather than trying to dump the waste heat?

paulr2006 · 20-05-2010, 11:11

You would be better venting the heat outside if possible as during the winter months the hot air in the loft would likely cause condensation which could well have an adverse effect on your roof timbers

Jezzar · 20-05-2010, 11:13

Well, I've actually stripped it to the minimum (as I see it anyway)

2 x Sky boxes
1 x CCTV server
1 x Linux server
1 x ADSL router
1 x Firewall

I did have a big NAS, but that had to go, letting the Linux server take over its job

coopermanyorks · 20-05-2010, 20:14

I have just been up in my loft to store some junk and its a furnace as nip says in post 2

bobcar · 20-05-2010, 22:27

I don't see why the temperature in the loft should make any difference. The fan is taking in cooler air from downstairs and pushing it up into the loft not taking air from the loft itself.

Of more concern would be the possibility of moisture though that would probably also be okay since the same quantity of moisture won't be produced as from a bathroom or kitchen. The roof space will be vented so a small amount of moisture is okay.

bilsat · 21-05-2010, 05:50

We had a lot of equipment in one small space so when we decorated the living room I opened the disused chimney and installed slats so that any equipment had ventilation, this had helped keeping it cool.
As an idea could you use a kitchen/bathroom extraction kit?

FlatProblem · 21-05-2010, 10:08

Quote:

Originally Posted by bilsat

We had a lot of equipment in one small space so when we decorated the living room I opened the disused chimney and installed slats so that any equipment had ventilation, this had helped keeping it cool.
As an idea could you use a kitchen/bathroom extraction kit?

I'd second that idea - use an extractor and vent it outside, not into the loft. Around your roof there should be gaps for ventalation that you can use to stick the end of the extractor out of.

Make sure its a very quiet fan (doens't need to be very powerful as you're not extracting wet air) or you'll be awake due to the noise rather than heat! It wouldn't be difficult at all to wire it up to a thermostat so that the fan only comes on when it gets too hot.

Might be an idea to put some kind of filter on there so dust, insects, volcanic ash etc dont dirty up your kit.

The best option would be air con, but if the extractor will do the job then you'd save some cash.

Jimmy Connors · 21-05-2010, 23:07

I used to have this problem a few years ago in my flat. I bought a portable air-con unit which did the trick. Stick the hose out of the window and you can cool a room drastically. I have proper air-con fitted now - so my flat is lovely and cold all the time. I can not abide heat!.

pocatello · 22-05-2010, 01:57

Its called a whole house fan.

Lakeuk · 22-05-2010, 22:38

Could you down size, change the two servers for an atom motherboard which will give of less heat put should pay for it's self in the cut on the electric bills

Jezzar · 25-05-2010, 16:21

Quote:

Originally Posted by pocatello

Its called a whole house fan.

pocatello has it there; from wikipedia:

"A whole-house fan pulls hot air out of a building and forces it into the attic space. This causes a positive pressure in the attic forcing air out through the gable and/or soffit vents, while at the same time producing a negative pressure inside the living areas which draws cool air in through open windows."

I have since hooked up the case fan and mounted it into the ceiling. It still got to 28 degrees on a fairly average evening, so more power is necessary I think! I guess an inline extractor fan would be a cost effective way of doing it by the sounds of it. Whole house fans look a bit difficult to get hold of outside the states, but I will do a bit more digging around I think.

Failing that, it will have to be a portable air con; but the noise and running costs might be prohibitive.

Jezzar · 25-05-2010, 16:23

Quote:

Originally Posted by Lakeuk

Could you down size, change the two servers for an atom motherboard which will give of less heat put should pay for it's self in the cut on the electric bills

That is one idea; but the sky boxes themselves generate quite a lot of heat (and noise).

The Linux server has enough compatibility issues with the bog-standard Pentium chip in it; but an atom might be an option for the windows box I guess.

bobcar · 25-05-2010, 18:03

Quote:

Originally Posted by Jezzar

I have since hooked up the case fan and mounted it into the ceiling. It still got to 28 degrees on a fairly average evening, so more power is necessary I think! I guess an inline extractor fan would be a cost effective way of doing it by the sounds of it. Whole house fans look a bit difficult to get hold of outside the states, but I will do a bit more digging around I think.

I fitted a fan to extract from a shower, a bathroom and a toilet (rather than one in each room) and vented it off via a vent tile in the roof because the air contained moisture. The fan fitted in the loft and I used flexible ducting to/from the fan. It has 3 speeds but I usually only need to use the low setting.

It was about 10 years ago I did this and the fan cost about £100. Unfortunately I can't remember the name of the place I got it but it was the local electrical suppliers (trade to electricians etc) so I guess that would be your first point of call.

moviemonster · 28-05-2010, 11:03

I have a spare room upstairs that has been converted into a cinema room. Their is a portable air-con unit in the room and the tube goes through the ceiling into the loft.

20-05-2010, 10:34	#1
Jezzar Forum Member Join Date: Apr 2004 Location: Berkshire Posts: 51	Venting hot air into loft Wondering if anyone has done this? I have a growing number of sky boxes, computers etc, and the whole room is an oven. I'm planning to put them in the cupboard, and as it's upstairs, cut a hole in the ceiling and put a 12cm case fan in it to help push the heat upwards into the loft space. Has anyone tried anything similar? Any thoughts appreciated!

20-05-2010, 10:40	#2
njp Forum Member Join Date: Dec 2004 Posts: 21,646	My thoughts are that in summer, your loft space probably gets very hot indeed, and that trying to use it as a dump for hot air from below probably won't be very effective. And that by placing all your power-hungry devices in one small space, you will make the cooling requirement more critical, and increase the risk of hardware failure.

20-05-2010, 10:59	#3
Jezzar Forum Member Join Date: Apr 2004 Location: Berkshire Posts: 51	You may have a point there njp. The heat's taking over the top floor at the moment though, and kept us awake last night so am running out of options. Anyone got a better solution?

20-05-2010, 11:09	#4
njp Forum Member Join Date: Dec 2004 Posts: 21,646	How much power are we talking about here? The weather hasn't even started to get hot yet, so I fear for your future! Does everything have to be left on at all times? Could you manage the energy consumption, rather than trying to dump the waste heat?

20-05-2010, 11:11	#5
paulr2006 Forum Member Join Date: Jul 2007 Location: Nottinghamshire Posts: 1,098	You would be better venting the heat outside if possible as during the winter months the hot air in the loft would likely cause condensation which could well have an adverse effect on your roof timbers

20-05-2010, 11:13	#6
Jezzar Forum Member Join Date: Apr 2004 Location: Berkshire Posts: 51	Well, I've actually stripped it to the minimum (as I see it anyway) 2 x Sky boxes 1 x CCTV server 1 x Linux server 1 x ADSL router 1 x Firewall I did have a big NAS, but that had to go, letting the Linux server take over its job

20-05-2010, 20:14	#7
coopermanyorks Forum Member Join Date: Jan 2003 Location: In Gods Own County Posts: 20,678	I have just been up in my loft to store some junk and its a furnace as nip says in post 2

20-05-2010, 22:27	#8
bobcar Forum Member Join Date: Sep 2004 Posts: 14,718	I don't see why the temperature in the loft should make any difference. The fan is taking in cooler air from downstairs and pushing it up into the loft not taking air from the loft itself. Of more concern would be the possibility of moisture though that would probably also be okay since the same quantity of moisture won't be produced as from a bathroom or kitchen. The roof space will be vented so a small amount of moisture is okay.

21-05-2010, 05:50	#9
bilsat Forum Member Join Date: Mar 2005 Posts: 427	We had a lot of equipment in one small space so when we decorated the living room I opened the disused chimney and installed slats so that any equipment had ventilation, this had helped keeping it cool. As an idea could you use a kitchen/bathroom extraction kit?

21-05-2010, 10:08	#10
FlatProblem Forum Member Join Date: Jul 2006 Location: Harrogate, North Yorkshire Posts: 901	Quote: Originally Posted by bilsat We had a lot of equipment in one small space so when we decorated the living room I opened the disused chimney and installed slats so that any equipment had ventilation, this had helped keeping it cool. As an idea could you use a kitchen/bathroom extraction kit? I'd second that idea - use an extractor and vent it outside, not into the loft. Around your roof there should be gaps for ventalation that you can use to stick the end of the extractor out of. Make sure its a very quiet fan (doens't need to be very powerful as you're not extracting wet air) or you'll be awake due to the noise rather than heat! It wouldn't be difficult at all to wire it up to a thermostat so that the fan only comes on when it gets too hot. Might be an idea to put some kind of filter on there so dust, insects, volcanic ash etc dont dirty up your kit. The best option would be air con, but if the extractor will do the job then you'd save some cash.

21-05-2010, 23:07	#11
Jimmy Connors Forum Member Join Date: Apr 2003 Location: Home For The Bewildered Posts: 86,545	I used to have this problem a few years ago in my flat. I bought a portable air-con unit which did the trick. Stick the hose out of the window and you can cool a room drastically. I have proper air-con fitted now - so my flat is lovely and cold all the time. I can not abide heat!.

22-05-2010, 01:57	#12
pocatello Inactive Member Join Date: Mar 2010 Posts: 8,622	Its called a whole house fan.

22-05-2010, 22:38	#13
Lakeuk Forum Member Join Date: May 2001 Location: Kendal, Cumbria Posts: 1,639	Could you down size, change the two servers for an atom motherboard which will give of less heat put should pay for it's self in the cut on the electric bills

25-05-2010, 16:21	#14
Jezzar Forum Member Join Date: Apr 2004 Location: Berkshire Posts: 51	Quote: Originally Posted by pocatello Its called a whole house fan. pocatello has it there; from wikipedia: "A whole-house fan pulls hot air out of a building and forces it into the attic space. This causes a positive pressure in the attic forcing air out through the gable and/or soffit vents, while at the same time producing a negative pressure inside the living areas which draws cool air in through open windows." I have since hooked up the case fan and mounted it into the ceiling. It still got to 28 degrees on a fairly average evening, so more power is necessary I think! I guess an inline extractor fan would be a cost effective way of doing it by the sounds of it. Whole house fans look a bit difficult to get hold of outside the states, but I will do a bit more digging around I think. Failing that, it will have to be a portable air con; but the noise and running costs might be prohibitive.

25-05-2010, 16:23	#15
Jezzar Forum Member Join Date: Apr 2004 Location: Berkshire Posts: 51	Quote: Originally Posted by Lakeuk Could you down size, change the two servers for an atom motherboard which will give of less heat put should pay for it's self in the cut on the electric bills That is one idea; but the sky boxes themselves generate quite a lot of heat (and noise). The Linux server has enough compatibility issues with the bog-standard Pentium chip in it; but an atom might be an option for the windows box I guess.

25-05-2010, 18:03	#16
bobcar Forum Member Join Date: Sep 2004 Posts: 14,718	Quote: Originally Posted by Jezzar I have since hooked up the case fan and mounted it into the ceiling. It still got to 28 degrees on a fairly average evening, so more power is necessary I think! I guess an inline extractor fan would be a cost effective way of doing it by the sounds of it. Whole house fans look a bit difficult to get hold of outside the states, but I will do a bit more digging around I think. I fitted a fan to extract from a shower, a bathroom and a toilet (rather than one in each room) and vented it off via a vent tile in the roof because the air contained moisture. The fan fitted in the loft and I used flexible ducting to/from the fan. It has 3 speeds but I usually only need to use the low setting. It was about 10 years ago I did this and the fan cost about £100. Unfortunately I can't remember the name of the place I got it but it was the local electrical suppliers (trade to electricians etc) so I guess that would be your first point of call.

28-05-2010, 11:03	#17
moviemonster Forum Member Join Date: Jul 2008 Posts: 161	I have a spare room upstairs that has been converted into a cinema room. Their is a portable air-con unit in the room and the tube goes through the ceiling into the loft.

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Venting hot air into loft