What’s the best wall height for a ductless mini split heat pump?
Hello out there,
I’ve been heating my home with a Mitsubishi Hyper Heat FE-18 heat pump for over a year now and learned a valuable lesson about which wall to place the unit on. I “hid” it on a partition wall, 90 degrees to an exterior wall, and place it up over a wide opening (8 to 9 ft. opening) from the LR to the DR. I thought the air circulation would be fine with the vanes pointing straight down supplying hot air to both the LR and the DR. I learned that the vanes do not go in a straight vertical position, they are always angled a little, understandably (now) so heat isn’t being forcing directly down a wall. However, last winter there were some problems with the vanes not returning to a down position after the unit went into its defrost cycle for which the vanes moves to a horizontal position. The end result was a DR with warm air pooled at ceiling level and not very good circulation of the heat. If I moved to the other side of the doorway into the LR, the temperature dropped dramatically just a few feet from the warm room.
So this year, I’m about to have the unit relocated to the exterior wall in the LR, near the partition wall/opening to DR. It is pretty pricey to have it done so I want to make sure I get it right this time. I feel pretty confident about the location, but not sure what to do about the HEIGHT. I rarely use the AC; it’s the heating that I’m concerned about. It seems that placing the unit only inches from the ceiling (which is what the HVAC guy says is where they should be installed), is asking for the heat to stay in the top portion of the room. An apartment I lived in had a Monitor floor model hot air space heater and it did a terrific job. I also remember an article by Marc Rosenbaum saying that he had a heat pump and had a similar problem and would recommend putting them lower on the wall. Can anyone point me to that article? Or has anyone had experience mounting these units lower on the wall?. Any info base on first hand experience would be most helpful. The relocation is coming up soon. Thank you!
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