Choosing a Portable Heat Pump
Recommendation on portable heat pumps?
I’m looking to heat a few small workshop spaces that are detached (in a garage & in a barn). I do have a Mr. Buddy and one of those “jet engine” heaters but I’d like to get away from the Dinosaur Juice 🙂 Also, I’ve no need to heat when it’s a January blizzard here in Wisconsin — but down to 32F ambient would be ideal.
There’s 1 portable that just came out with an inverter, and it’s really tempting: Midea/Toshiba Duo Smart 14K (model# MAP14HS1TBL/RAC-PT1411HWRU). It uses R32 refrigerant. Sadly, it’s still a typical 40F ambient shutoff. Manual with details: https://images.thdstatic.com/catalog/pdfImages/4a/4a3ff6f0-a7df-44a9-9b6f-68b46da1f56a.pdf
Another inverter portable mentioned on GBA that uses R410a was Climax Air’s VS12 but sadly it only cools 🙁
40F ambient is still the cutoff for portables??
I realize 32F ambient means the condenser will need to be defrosted but I’d assumed there was a manufacturer now making (in 2021) portables that could do a defrost cycle …
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Wouldn’t a cold weather mini split serve? There are name brand units online for about $850 that are good down to 5 degrees.
$850?! Do you have a link?
The least expensive way to go is DIY b/c we all know labor is most expensive, and the cheapest minisplits @ big box stores around here are > $1000.
I wanted portable instead of fixed mount because it would mean 1) no professional installation required, and 2) I can move the heater around to different workshops & even to our RV. I can get rid of (1) with DIY models, but again: the cheapest I found is $1300.
After much looking & reading, it looks like all portables still cut out at or just above freezing.
I looked at PTACs as an alternative to DIY minisplit because I wouldn't have to worry about linesets but PTACs/PTHPs have a bad rap ...
The unit you linked to has only one tube expelling air from your building all the air this unit expels will be replaced with uncondioned air leaking in thru the gaps in your building. On a warm day I suspect this unit would actually warm the room when set for cooling.
I have not been impressed the portable I have seen if you decide you must have one get one with two tubes connecting it to the outdoors.
Here is the page from Amazon: https://www.amazon.com/dp/B01DVW6G42?tag=aclabnew-20&th=1. One buyer noted that these units come precharged but require a vacuum pump ($100) to complete the installation. That said, I didn't read enough to learn if you could self-install and maintain the warranty.
I just recently went down this road and it seems like Mr Cool is really the only brand offering precharged line sets according to Ingram’s. It seems like most of what is marketed as DIY still relies on a tech to come pull a vacuum and charge the lines.
Much of the cost depends on the size of the equipment—which of course depends on the size of your space, how well it’s air sealed/insulated, etc.—but this one from Mr Cool is a complete package for 9,000 BTU and goes down to 5F for less than $739. That price doesn’t include freight, but Home Depot has it for about $50 more with free pick up at their stores.
Brian, I'm not sure the OP could use the Mr. Cool unit you mentioned. Mr. Cool has two different lines of mini splits. One is a DIY line that includes quick connects and a 7 year warranty if the buyer installs it himself. The other is the "Advantage" line without quick connects (flared fittings instead). Its warranty is void if the person installing it isn't licensed. Those units are half the price of the equivalent DIY units.
Even the non-diy units are not that difficult to install. The compressor itself is precharged with R410 but the linesets are only filled with nitrogen. The system does not require charging with R410 but it does require pulling a vacuum on the line sets before opening the valve at the compressor to fill it with the precharged freon from the compressor.
It can be done by someone who is confident in his/her abilities but a person would have to school themselves using videos on Youtube to do it. I elected not to go that cheaper route and went with the DIY line because of the warranty and peace of mind the quick connects provide. important to me.
Thanks for catching that, Eric. When I spoke to the tech at IWAE he referred to both as “pre-charged” interchangeably. I didn’t realize that there was a fundamental difference as to where that charge exists.
I just looked over the install instructions for the Advantage I linked to, and in addition to the need to flare and draw a vacuum (which I agree, isn’t a huge deal) it said that the charge is based on a 16ft line set length. It appears that any more or less necessitates recalculating the charge, which definitely takes it out of the typical DIY realm.
Thx for everyone's replies.
My OP was for _portable_ units and I posted that way, in part, b/c the debate about DIY vs professionally installed minisplits has been going on ... well, since I joined GBA so there's plenty of info about that.
It looks like the answer to my question is actually: "None; there are no such portables".
There is a somewhat portable window heat pump coming out that is a true split system but it's not available yet. https://www.gradientcomfort.com/