Computer Equipment Room and Fresh Air Circ with HVAC?

[jfrelin]

Gents -

I live in Alaska and due to my job responsibilities and working from my home, I have a small room (8x10) thad I've put a dedicated split 2 ton A/C unit to keep the room cool due to the high BTU output of some of the gear I run.

Now in the winter months, the outside air is nice and cool and trying to figure out a way to circulate fresh air from the outside into the room with a direct vent back to the outside return. (The room is completely sealed from the rest of the house due to the A/C unit and some fire suppression stuff).

I think I could save quite a bit of $$ on A/C costs during 6 months of the year when it's mild humidty out and temperatures are below freezing.

I'm thinking of two electric dampers on the supply and return to the outside of the house (so they can close prior to the fire suppression agent dispersement), but not sure how to place them in the room to allow proper air flow, yet to allow the A/C unit to still run as needed as suplementary/etc.

Short of hiring someone to come out and look, anyone have some thoughts? I'm an engineer, but not one that knows HVAC hence why I'm asking.


Thanks in Advance,

-jjf-

[therinnaiguy]

Get yourself an ERV (Heat Recovery Ventilation unit) and duct it into your home. Very cost effective and it will do what you want it to do.

[Bill Arden]

I'm in a similar boat. I have lots of equipment and I live in Northern MN and I think it's silly to run the A/C when it's cold outside.

Last summer I used a window A/C unit again. And I used a small window fan in the spring and fall.

But I swapped the 21 inch tube monitors out and am now adding liquid (non refrigerated) cooling to the computers and equipment.

The laser system already has a cooling system and I am looking to use (Geo-thermal ground source) ground water to keep it cool as it puts out about 1500Watts of heat.

So if things go well I should be a lot better off.

[alternety]

Possibly just a temperature controlled fan to move air, simple ductwork, dampers (something that closes fast), and a filter. A variable speed fan or squirrel cage blower would be best rather than just on/off. Something to keep the mosquitoes out. As I recollect that can be anything with holes under 4"

Just point the ducts for good circulation. You don't want to get that stuff too cold or too much fluctuation. If you need the air conditioner to supplement I would probably close the outside air off and do one or the other but not both simultaneously. You might want some adjustable dampers in addition to just open and closed. If it gets real cold outside you may have too much circulation even with the blower turned off.

Keep you eye out for condensation conditions as temps change.

A heating shop could make you the ductwork.

[Mikey]

Does anybody know how the cost to run an AC system varies with ambient temperature? I'll bet with all the fancy technology today it might not be very costly just to keep running the AC.

[jadnashua]

One of the last things you need in the middle of winter is to be running the a/c to cool things off - it will take any minimal moisture you might have left in the house and suck it dry unless you go to the expense of adding a humidifier, too. Think Death Valley dry...not good for you or your equipment - the static could be really nasty.

I'd look into a heat recovery ventilation system as already mentioned, which would retain most of the moisture, and provide some fresh air. They aren't perfect in their recovery, so the incoming air would be cooler than the outgoing air. This will depend somewhat on the speed of the fan. I'm pretty sure you could get the temperature in the room where you want it. You might be able to find one with some bypass controls that would make it cooler or warmer, varying the mix of air.