Yes there are units that are specifically rated for cold operation. Most of the manufacturers have systems specifically intended for computer rooms that have that feature standard, but many others have it as an option.
It’s basically just a pressure switch that keeps the outdoor condensor fan from running until the internal pressure rises sufficiently, and then cycles the fan as needed to control the system pressure. Mark Radabaugh Amplex 27800 Lemoyne, Ste F Millbury, OH 43447 419-837-5015 x1021 [email protected] > On Sep 28, 2015, at 1:43 PM, Nate Burke <[email protected]> wrote: > > I'm looking to add backup cooling to a small computer room, <200sqft. > Primary cooling is via a RTU (roof top unit), but I can't put that on our > generator (240v genset vs 480v RTU). I'm thinking like a 2 or 3 ton Split > system would be perfect. Problem is we're in the midwest, and outdoor > temperatures can drop to 0 or below over the winter. Looking at the split > systems, nobody seems to know if they will work for cooling with outdoor > temperatures that low. Online searching has yielded results for Heat Pump > units, where they want to Heat with low temperatures. Has anyone had > experience with Split systems cooling with low outdoor temperatures? Are > there special compressors built for that use? I have heard about putting a > thermostat on the fan line to cut out the compressor fan below ambient X > temp, or shrouding the compressor to keep wind from blowing through it. But > have not been able to confirm from any HVAC contractor the validity. > > This would only be for backup use, RTU Failure, or power outage. The RTU is > handling the load normally without an issue. My Current Backup is Movincool > units, but I want to reclaim the floor space, and make it more permanent. > >
