Looking for ideas to vent a 2nd floor utility room

Question

I'm a software developer who's worked at home for 20 years or so. I recently moved to the country, and have all my IT equipment in a 2nd floor "utility room". This room also has the water heater (electric) and a passive water treatment system for well water. But, most/all the heat is generated by the IT equipment, not other infrastructure.

This room generally sits between 85F and 90F due to the large quantity of servers and network equipment exhausting waste heat. There is one small ceiling vent from the HVAC (intake, not exhaust). The room wasn't really designed for the amount of heat being generated. But I'd like to bring the temps down to 80F or so.

In my old (suburb) house, I had a similar setup, and installed what amounts to a dryer vent in the door coupled with a free-standing bathroom ceiling vent box to exhaust the waste heat to the hallway. I'd like to do something similar, but slicker. (The vent box eventually burned out, so clearly wasn't rated to run 24 x 7).

I'm basically looking for ideas or pointers to cheap, but effective solutions. In the winter, it makes sense to send the waste heat into the house, e.g. the hallway outside the room, where it can offset any heating needed. But in the summer, it makes more sense to push the waste heat outside in some way. I don't mind manually switching things a couple times a year, and I suppose could automate some of that if it gets too burdensome.

I really don't want to add a spot cooler or anything that would consume significant power, as I don't think the problem warrants that. Cycling cool air to/from the rest of the house would be OK.

The room may have a way to vent air into the soffits, or at least I could install something to do that if there was something that would work and not allow outside air (or critters) to back-flow in. I'd also like to not create any code issues, fire issues, etc.

Ideas are appreciated. Being in the country, there aren't a lot of pros out here, so it will pretty much be DIY via Lowes or Amazon. I have lots of skills including electrical and electronic, so can probably build just about anything within reason.

Thanks...

Answer 1

I'd suggest that your best bet would be to go with the bath vent fan again. To satisfy your different requirements:

• If you don't want to have to replace the fan itself every couple of years, look for a "commercial grade" fan that's designed for continuous duty.
  • Bear in mind that the added cost of the "upgrade" may be roughly equal to the more frequent replacement cost of a standard residential grade unit offset by the work necessary to do the replacement. You make that call.
• Run duct through the attic to a roof/soffit/wall vent.
  • It's not recommended to just dump more hot air into the attic. It's probably not as critical in this case since it's not especially humid air as it would be from a bathroom, but in the summer, you don't want the attic space getting any hotter than necessary as it's bad for the roofing material and it's just more heat at the ceiling for your AC to fight against.
• Install a second duct to a location indoors where you'd like to dump the heat in the winter. To make the switch over easy/easier:
  • Open a relatively large area of the utility room ceiling
  • Box in an area in which you'll mount the fan
  • Install both sets of duct work, attaching one set with a hose clamp
  • Screw in a plywood panel to cover the "extra" opening. Removing the screws will give you easy access to the part of the fan where you can make a simple hose-clamp based duct change over in the fall and spring.

For the HVAC vent in the ceiling, you may want to cover it with a magnetic sheet in the summer time to prevent drawing this hot-box air into your HVAC system where your AC unit will have to work even harder to cool it. In the winter, you can pull the magnetic sheet off to draw "free" heated air in to help disburse it throughout the house. (I'm about to switch from AC to heat, and I've got a magnetic sheet to cover the duct that sits directly below my server in my office - I let the AC blow up it's skirt in the summer and block the heat off in the winter. The magnetic sheet works perfectly for this.)

You may need to put a grill into the utility room door to allow some airflow into the room to improve the efficiency of your new ventilation system. Having the bath fan effectively trying to pull a vacuum in the closet probably will have an impact on its service life.

For some additional geek points, you could hook up both ducts to different ends of a Wye with automated dampers that will open one and close the other based on your home automation system's reading of the thermostat - open the "inside" duct/close the "outside" duct when the system is heating and vice versa. You could also put an automated damper on the HVAC return duct in the utility room instead of a simple magnetic sheet, controlling it based on heating/cooling requirements. That could be v2 of the project.