Mini Split- Wall mount or pad

[Bob Borzelleri]

If UPS recovers from storm related delays, I should be getting a MR Cool Mini Split unit for the shop next week. It will replace a ceiling mount 240V heater that I have used since building the shop in 2004.

Wondering if anyone who has mounted the condenser on a wall mount bracket could comment on noise/vibration transmission into the shop while the condenser. is running. Alternative is concrete or lightweight pad.

[glenn bradley]

I have two Pioneer units. Wall mounted with their mounts and isolating foot pads/mounts. There is little noise from the units themselves. They do vibrate the wall just a bit and my straight edges and GCS rails that hang on that wall will sometimes rattle about a bit. We live in town but in a sort of "horse country" community. This means we keep critters so standing them on a pad was not a good option. If you can, I would stand them on a ground pad.

[Steve Mathews]

I have two Pioneer units. Wall mounted with their mounts and isolating foot pads/mounts. There is little noise from the units themselves. They do vibrate the wall just a bit and my straight edges and GCS rails that hang on that wall will sometimes rattle about a bit. We live in town but in a sort of "horse country" community. This means we keep critters so standing them on a pad was not a good option. If you can, I would stand them on a ground pad.

Is there anything that you can think of to lessen the vibration short of placing it on the ground? Beefing up the wall if the framing is accessible, etc.

[Paul J Kelly]

I tried both.

The wall mount from Mr Cool was adding vibrations that affected an adjacent room. I ended up on the concrete/lightweight pad and it is now pretty silent.

PK

[glenn bradley]

Is there anything that you can think of to lessen the vibration short of placing it on the ground? Beefing up the wall if the framing is accessible, etc.

If I walk over to that wall and place my hand on it the noise stops. I could move my GCS rails but they fit so well there . Truly my shop is mostly a noisy environment. I have a half a dozen ear muffs hanging on various machines and setting near the vacs. When the machine stops you can hear my gazillion hours of random music tracks playing. The only time I hear the rattling is if the music is between tracks. When the DC is on and I am running the tablesaw with earphones on the rattling GCS rails seem to disappear

[Jim Becker]

I bought a composite pad from SupplyHouse.com for my minisplit. Far simpler than a wall mount and the only space downside is the unit has to be just a hair farther from the wall. There's zero vibration transfer to the building other than anything that might from from the lineset.

IMG_3059.jpg

[Robert Hayward]

My Pioneer mini split compressor is wall mounted to a CMU wall. Cement Masonry Unit, AKA concrete block. I do not know if it is running or not, simply cannot hear or feel anything. The place I bought from said either way, wall or pad mount was okay but the unit would run more efficiently wall mounted at least 12" from the ground. Seems the more air flowing around the compressor the cooler the unit runs.

[Bill Dufour]

If it is a heat pump you should mount it 12" off the ground or so. so snow does not block airflow. I prefer a cast concrete pad to a plastic one that can vibrate.
Bill D

[Mike Wilkins]

If you live in an area that gets snow of up to a couple of feet, wall mount would be a better option. You could probably place some vibration isolators between the wall and the mounts (rubber or some equivalent).

[Jack Frederick]

I have two wall mounted units and yes the adjacent room definitely gets a bit of a hum. Not terrible, but at times you will pick it up. There are stands available so you can ground mount them. I have seen ground mounted units in cold climates where in the defrost mode ice with the unit sitting on a pad will build up in the condensing unit. If the unit is on a pad, ice can block the drain and the ice will build. I have seen it freeze the condenser fan in position causing all kinds of problems. make sure the condensing unit is level and if ground mounted that the supporting pad is not going to tip. I like the wall brackets, but do give some care to where it is located. Getting them off the ground also helps keep them cleaner.

[Walter Mooney]

Bob, my Mr. Cool unit is the DIY unit, and came pre-charged for and with (IIRC) 25’ of lines. I needed about seven of them. If you get a similar unit, and don’t need all 25’ of line, the excess line MUST remain coiled up HORIZONTALLY at the outdoor unit. So, there may not be a way to do that with the exterior part of the system being wall-mounted! And I poured my own pad for it— two sacks of Sakcrete and a 2x4. Poured it one day, set the unit on it the next!

Good luck. I thought the install was extremely easy.

[Dan Friedrichs]

The Pioneer unit in my garage is wall-mounted, and is noticeably and annoyingly loud even in the attached house. Note that inverter compressors vary their speed quite a bit, too, so it's not like a constant hum - it changes frequency, which (imho) makes it even more noticeable.

I'd highly recommend pad mounting if possible.

[Bob Borzelleri]

Thanks to all for responding. Looks like a pad is the way I will go. Good to know that the excess line needs to be coiled horizontally.

[Jack Frederick]

“Coiled horizontally?” I know what it means, but if confused by the term lay it off left/right, L/R in a serpentine fashion. Do not coil it in a circular way as it can trap oil in the lines and the unit will not be happy with it. A couple pieces of Uni-strut on the wall and appropriate size strut hangers are the best way to mount it that I have found AND, don’t kink the line set.

[Patty Hann]

I bought a composite pad from SupplyHouse.com for my minisplit. Far simpler than a wall mount and the only space downside is the unit has to be just a hair farther from the wall. There's zero vibration transfer to the building other than anything that might from from the lineset.

IMG_3059.jpg

"Composite" as in...what?
I was reading about the different pads, and they all seem to be styrofoam (polystyrene/EPS) coated with a cement like material.
Is yours like that or it something else, something a bit more substantial than polystyrene?
And I noticed unit is bolted to the pad, so I'm thinking it's not polystyrene (but I may be mistaken)