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Air conditioner installation in cold climates

For best heating performance in a cold climate, the indoor unit of an airconditioner should be installed close to the floor.
Many aircondiioner manufacturers, including Panasonic, specify that the indoor unit should be mounted near the ceiling.
Mounting the indoor unit near the ceiling works well for summer cooling, because the cold air from the unit will reach all the way to the floor.
When a high-mounted indoor unit is heating, the warm air from the unit rises towards the ceiling.
With my high-mounted unit, the temperature at foot level is up to six degrees colder than the temperature at shoulder level. A three degree difference can be enough to make the room feel stuffy. A six degree difference is enough to create both a warm head and cold feet.
I had to spend another $600 to install a ceiling fan to correct the air conditioner’s poor temperature distribution!

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Welcome to the Community @LeonArundell,

Many do not notice but there are options to suit. My typical Daikin splits are mounted near the ceiling but my main heating is hydronic so they are not used in heat mode very often.

For those who depend on splits for heating in colder areas this is a random example of what is available.

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A good fan in the head unit should mix the air within a room. If the system is designed for the room and the fan is not working effectively (say the filter hasn’t been cleaned and it isn’t working efficiently), then mixing could be poor resulting in stratification of the air within a room.

Maintenance is also important for efficient heating/cooling.

Warm air rises, so unless the fan is able to mix the room air well, it faces the same potential problem as the high mounted units. Stratification within the room with exception of immediately in front of the fan unit.

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The manufacturer has confirmed that the unit was installed according to specifications, and is working as designed. Measurements were taken during the first heating season after the unit was installed.

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I just posted something similar as I hadn’t seen your post. I agree 100%. For heating, floor mounted units are preferable.

I find ceiling fans work well particularly on their winter cycle which moves the warm air in the room down to floor level. They don’t need to be on a fast speed, they just need to help circulate the air. Also ensure the A/C vanes are pointing downwards and not on the usual auto movement if you have Split Systems, we have Ducted so ours vent from the ceiling and we set the diffusers to suit where we want the air to be directed towards.

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Some fans have a slide switch on the fan, just above where the blades attach to the main body. The switch reverses the fan direction blowing air towards the ceiling and then to the corners/cornices and down the wall. This way you don’t feel the air moving as much causing a cooling effect.

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It’s what we found worked best with our RC split systems. As the Choice split systems reviews relate some air con fans have greater throws, are more powerful than others. We sometimes in Winter use our ceiling fans in winter to help circulate the room air, and always do in summer.

In winter we have the option of using hydronic panel heaters which are mounted under the windows as per normal. They cause the room air to circulate as the warm air rises on one side of the room and draw cooler air across the floor. An old fashioned pedestal fan on stand seems to do the trick

Some of the RC air con manufacturers supply a floor mounted head option that draws air in on the lower front and blows heated air out from the top. This is the opposite of how a standard wall mounted head unit is configured.
EG https://www.mitsubishielectric.com.au/console-split-system-air-conditioners.html

It appears that if your priority is heating rather than cooling this may be a better option. We’ve had OS accommodation in colder locations wth this type of air con. For those of us who need summer cooling and winter heating, ceiling fans appear to be the solution/ compromise for larger rooms where the split air con is not able to provide adequate circulation.

P.S. For our timber floored off the ground Qld cottage, every winter encourages me to look at installing under floor insulation.

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I was keen to use floor mounted split systems because I mostly use AC for heating, and it made more sense to draw in cold air from the floor and put out warm air closer to seating level rather than from a wall mounted unit. I didn’t go that way because the floor mounted units made by MHIAA are rated as much less efficient than the standard units, and they cost more. This makes ceiling fans a more cost effective remedy.

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