DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   HVAC (
-   -   Mini Split for heating in cold climate (

landev 01-18-2009 12:35 PM

Mini Split for heating in cold climate
My power company has been pushing ductless heat pumps for heating in our area (northern Idaho.) Our temps generally are about 25-30 degrees F, though we get temps down to -20F at times. Most of what I've read states that heat pumps are not a good idea in colder climates, but some manufacturers state that their pumps work down to 0F. What I've not discovered is a table that shows the drop in efficiency vs. drop in temperature.

In looking at efficiency ratings in various heating sources, I am seeing that a ductless heat pump will cost 1/6th of what we are currently spending to heat with propane. We are interested in a single zone system for heating our main living area (~650 sq. ft.) which is now heated by a free-standing propane stove. We also have a propane stove in our master bedroom... the combination of two stoves and super-insulation are heating our whole house (1650 sq. ft..)

I am all for installing a ductless system if it would still heat at a reasonable level of efficiency at our average winter temps. We are looking at Fujitsu, Mitsubishi, and Sanyo units of ~32Kbtu heating potential.

Any info anyone might provide regarding efficiency, system recommendations, or whether this is not a good idea would be greatly appreciated.

Thanks in advance!


JohnH1 01-18-2009 02:49 PM

They will work great in the 30 deg or so range. After that as it gets colder the heat output is redused. I wouldent get rid of your existing heat for the really cold weather. Re: Efficency They are great use them for the heat when you can and go to the back up heat whenever you need to.

landev 01-24-2009 12:57 PM

After much looking around, it seems that Mitsubishi is now producing a 30Kbtu Hyperheat unit (PKA-A30FAL) that will run at 100% efficiency at 4F and will produce heat at 75% efficiency down to -13F. The efficiency vs. temperature graph of this unit shows typical efficiencies of Mitsubishi's other products as well as typical competitive units. The Hyperheat unit is quite spendy, but exactly what I'm looking for.

Why all manufacturers do not publish stats regarding efficiency as a function of temperature remains a mystery.


JohnH1 01-25-2009 11:13 AM

They do. It is in the install side of the documents. It is the responsibility if the trained pro to determon the correct system for the homeowner. Most homeowners dont understand enough to get that deep into the heat output at whatever temp outside. The manufactures are not trying to train the public on sizing and design. They have trained the pros to do that. You have more desire to know the background than the general public.

kt82 01-29-2012 07:05 AM

My power company has been pushing ductless heat pumps for heating in house (1650 sq. ft..)

-do your propane heaters vent to the exterior?

beenthere 01-29-2012 07:41 AM

I hope he has made a decision in the 2 years since he made this thread.

kt82 01-29-2012 08:23 AM

you never know.Quality decisions like that take time to ponder

beenthere 01-29-2012 09:52 AM

Not 2 years.

You were bored, and revived a couple old threads.

kt82 01-29-2012 10:08 AM

I am thinking of using the ductless system in my 1909 house .It has 4 rooms 1200sq feet .and I only use 2 of the rooms
Mr a/c man wants 4K for a new central heat and air and I was looking up if people are happy with there split systems
I just want info, data ,or good hunches
But now I must rush off to church

beenthere 01-29-2012 10:18 AM

Starting your own thread is the best way to get opinions about what you want to know.,

All times are GMT -5. The time now is 09:39 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1