My Node 0 Ventilation Solution (in Loft)

["rb_ziggy" <richard.boreham@xxxxxxxxxxxx>]

This always is topical at this time of year so I thought I'd post a
note on my recently installed solution. I've posted a few pictures
in the photo section (RB's Ventilation folder).  Comments on these
below.

I've been running a server in the loft since last autumn and knew
I'd need to sort out some ventilation for the summer as it gets
pretty hot in the loft in the summer. I was eventually prompted by
two events. First, the recent heatwave which forced me to close the
server down because it was hot to the touch - the PC box that is!
(I'm pretty sure it reached 40 deg C in the loft). Second was the
acquisition of a UPS from Andy Whitfield who warned me not to cook
the batteries and 40 deg ambient seemed to be in that category.

So to the gallery:

The 'Overall View' shows most of the boxes in the loft. The patch
panel on the right; a big handbuilt MDF box which houses the server
and gubbins (more of which below); and on the left you can just see
the Comfort box.  This pic also shows part of the reason for the
heat problem. The house is tiled with dark grey/black tiles and
underneath is the black roof lining. In the sun it just soaks up the
heat and dumps it into the loft space (reverse problem in the
winter - it gets colder than the surroundings). The long term
solution will be to insulate into the roof timbers but thats a
fairly big and expensive job which I can't be bothered with at
present.

The 'Server Cabinet' shows the inside of the MDF box. It's not
elegant but it was very cheap to knock up and probably does the job
better than a bought unit. At the bottom is the PC and the Powerware
9110 UPS. Above these is a big Russound poweramp which takes its
feeds from the PC (running Xlobby and holding the MP3s plus other HA
stuff including ACE and Comfort's CWI software) and distributes to
speakers around the house.  The cooling ducting outlet drawing air
from under the soffit outside can be seen at the left feeding cool
air to the inlet side of the UPS & PC. I was going to do something
neater with the end of the tube but this works fine and I'm not sure
now there is much point. The position of the thermostat (left side
with trailing white wire) can also be seen.

The 'fan' picture shows the location of the fan at the back of the
cabinet (ducting has been detached for the photo). This is an
Xpelair XIL100T axial extraction fan designed for bathrooms but
mounted the 'wrong way round' as it sucks air from under the soffit
and blows it into the cabinet. You can just see here the exhaust
fans on the UPS and PC.  I've left the backplane on the cabinet
short so there is plenty of space for the warmer air to escape.
Similarly, the top of the cabinet is only partially covered to allow
warm air (especially from the amp) out. The Xpelair fan is mounted
on some etherfoam as an antivibration mount. It's pretty quiet
anyway but I didn't want it rattling the box! The junction box on
the right is part of the fan, thermostat, mains wiring. The wiring
was a bit more involved as this fan has an overrun timer which needs
to be wired to the thermostat.

'Ducting' just shows the inlet duct disappearing down to the soffit.
The white duct comes with the Xpelair unit. I used some leftover
aluminium duct for the main run as its more robust and easier to get
past all the (40cm of) insulation.

'Thermostat' is just that. A 0-60 deg C 'make contact' (i.e.
normally open) thermostat. Came from Farnell (Look for KTS01141).
Set at 25 deg C.  Took a bit of tracking down but seems ideal for
this application.

So far I have to say it's working well.  Seems to keep everything
down to about a max of 25 degrees (fan has barely been off so far).
It's in 'beta' at present and I'll tidy things up once I'm sure its
all working well.

Next job is to sort out a UPS to PC control cable for the 9110. I'll
drop another note on that at a later date. As I mentioned above this
is one (of three) units that came from Andy Whitfield recently. He
did a good price on these and, so far, these seem pretty good.

Hope this is of interest to others.

Regards

Richard