HVAC: What's best for cold climates?

[Sbob]

My compressors are all on mounts attached to the foundation of the house FWIW. When I installed my last project they initially put it on some janky stand and I made them do the mount.

New construction it’s a good idea because nobody compacts the soil when they backfill. The downside to wall brackets is the compressor noise transfers into the house. As quiet as mini splits are there’s still some noise. I give the customer the option, by the time I get there the ground has settled.

 

[Sbob]

In one of our data centers one of the hvac units will temporarily shut down if it's very cold and windy. The wind blowing directly on the coil combined with a cold air temperature will cause the refrigerant to contract enough that the unit will temporarily shuts down due to a low pressure fault.

There’s a lot of units that only work down to 5° . You have to pay extra to get the units that work down to-15°

 

[Campgottagopee]

There’s a lot of units that only work down to 5° . You have to pay extra to get the units that work down to-15°

Mine is supposed to work to the -15

 

[Campgottagopee]

And the unit with the shortest run does work

 

[Milo Maltbie]

From what I read it's only under high winds with cold temps. Mine seems to have issues when it's in the 20's and the wind is ripping. I'm talking 25 mph +. I catch a shit ton of wind at my house. Apparently it will cool the coolant enough so it's not putting out the proper temps. It kinda makes sense. The head unit downstairs seems to work much better in these conditions than the upstairs unit. I'm guessing because it's an extremely short run vs the one upstairs.

That sounds like you have more heat loss from the longer upstairs circuit than from the downstairs one. Maybe it's just the length but probably the upstairs is more wind exposed. Maybe you even have air moving in the walls somewhere. Either way, hay bales upwind of the compressor won't help much.

mm

 

[Harvey]

some janky stand

I think this is what I have.

nobody compacts the soil

I'm going to ask about this. Probably no way to do it after the fact?

Mine is supposed to work to the -15

This is awesome. Mine is new and only rated to 10. If I get that out of it, I'll be happy.

Even 15 or 20 will probably save me some money. The question isn't how low will it go, but how low is it cheaper to use than propane, wood or whatever your backup is.

If -15 is real world you barely need backup.

So the shorter the distance from the outdoor unit to (what... the air handler?) is better?

 

[Campgottagopee]

Yes, the head unit in the bedroom which is in the basement. I'd say it's only a 6-8' run?

I could be all wet, but I'm going with hay bales this winter to see if it makes a difference.

When temps get into the single digits I fire up my kerosene furnace and propane stove. The heat pump just can't keep up. That said, it's very rare we get prolonged temps like that anymore.

How did your's perform in the colder temps last night?

 

[Harvey]

How did your's perform in the colder temps last night?

Good, as far as i know. I got it up to 72 degrees (from 64) in a couple hours.

I turned it back down before bed because it seemed wasteful.

 

[Sbob]

I'm going to ask about this. Probably no way to do it after the fact?

Give it a good soaking periodically, it will settle.