Mini Split Experience

[Ashful]

Does noise get transmitted to the interior when exterior unit is mounted on a wall? I'm thinking wood frame house.

I have only wall-mounted the most recent one of the three condensors I have installed. I figured they're so darn quiet sitting on the ground (literally, hard to hear if you have any traffic in the area), they would not translate anything thru the wall. This was only partially correct.

Like peakbagger, I do occasionally hear the faintest compressor noise from that wall mounted condensor, when my shop is dead quiet. Not frequently, as I'm guessing it only happens when it's in a particular mode, but it's not completely non-existent.

I'd have no qualms doing the wall mount again, depending on the situation. If absolute 100% dead silence is the requirement, sit it on a pad (or elevated stand) on the ground.

 

[peakbagger]

Bringing back an old thread for an an update, the mild weather in the Northeast has allowed me to heat the house entirely with my mini split for the last two days (mid January). Nice to have a break from running the boiler. Unlike last year the outdoors temps were colder than normal and I ran the wood boiler more in late November and December as day time temps weren't anywhere near last year. I pretty well now only run the mini split on days and nights where the temps are predicted to be above 15 deg F. It will run lower but the heat output is lower as it gets colder and the houses heating demand is rapidly rising so it runs out of capacity. If its clear and sunny out, defrost cycles aren't that frequent down at 20 F but add in some dampness either fog rain or snow and the unit does defrost frequently. Its decidedly more noisy during a defrost cycle. I still haven't bought a second small one for my second floor office so I depend on my original unit on the main floor.

I did have one windy snow storm that filled the outdoor unit partially with snow to the point that the fan wouldn't turn. I had to wait until a warm day and go at it with an electric heater on the outside blowing through the coils to break up the snow. One downside to the Mitsubishi unit is there is no easy way to remove a grille to get inside the case. I expect its for safety reasons but it means the all the ice and snow has to go out through a 1" drain hole in the pan. I just have a slanted roof on mine with open sides on the lee side of building. I have seen installations where the entire unit is enclosed with plywood spaced out on the sides going back to the wall extending up to slant roof so that all the air has to come up from under the unit and then exhaust out the grille. This should substantially reduce any snow from getting inside. I may elect to do that at some point. but this is first time it has happened in three years of operation.

 

[Ashful]

I have one of the Mitsu units sitting right on the ground, and snow has never been an issue, excepting one time we got several feet in a single day. Usually, the snow stays clear around it.

Ice is a different story, though. Mine is half under an overhang, and I have walked outside to hear the outdoor unit fan clanging against ice that built up on the housing. I usually just pull the disconnect, then slide a yard stick thru the grille to knock the ice loose. Takes less than five minutes, so not a huge deal, but I do wish their design did a better job of preventing that.

 

[peakbagger]

My unit is up off the ground about 4'. I have had to shovel out underneath it at least once but I do live in northern NH.

I have never had icicles in mine, I built a temporary slanted roof over it for winter use and ended up leaving it on year round

 

[Ashful]

I'm thinking of doing the same, but since it's partially hidden in a garden we can see from our family room, I have to figure out a way to make it look nice. Maybe a little doghouse with a tin roof or copper roof, or something similarly tasteful.

 

[DBoon]

I raised mine off the ground on concrete blocks after the first year. Snow wasn't a problem - it was running pretty much constantly so it would blow the snow away from the unit - but ice would accumulate in the bottom of the unit since it couldn't drain away after a defrost cycle. Now it drains clear so no more problems in that regard.

 

[georgepds]

Who has has had a mini split, Fujistu or Mitsubishi, in one of the colder parts of the world (like Northern U.S.) for at least a full season ? No need for AC..

1. How well they heat below 20 F, occasionally down to 0 F.
>Great (12k Fujitsu RLS2H, installed about 3 years ago, used mostly in shoulder season, and on vacation)

2. Problems
> None

3. Reliability and maintenance
> Clean the screen on the inside unit with a wash cloth every season

4. Electricity cost in winter
> Practically nothing.. I ran it for 2 weeks this winter on "low heat" while I was on vacation, and it used 40 kwh (I have it metered) . That's 2.85 kwh/day on the Ma/NH border in the dead of January, just about the draw of an old 100 watt lightbulb (2.4 kwh/day). At that draw it kept the house at 50.. There are 18 Anderson windows on that first floor. The temperature data loggers showed 45-50 degrees in various parts of the first floor

5. Noise
>None, perhaps a younger person can hear it, but I can hear neither the indoor nor outdoor unit, norcan my wife, who hears everything

6. New cost of unit(s) installed
> ~$4k before state rebate

Thanks
> You're welcome