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Stepside
12-02-2018, 07:08 PM
My shop is small, approximately 20' x 20' and insulated. For the last 30 years I have heated it with Propane. So a 30 year old furnace, $90.00 to fill a tank and the tanks have to be updated/replaced. Not to mention the 200 pound tanks are no fun to load and unload from my truck.

Is it time to put in a mini-split heating/cooling device?

Opinions, what would you use?

Pete

Ohio Mike
12-02-2018, 07:22 PM
Honestly I don't know what the weather is like in Kirkland Washington. The advantage of the mini split is you can get a heat pump, air conditioning and humidity control. That space is so small you could probably do it with a window unit.

chipmaker4130
12-02-2018, 07:30 PM
My shop is 24 X 36. I have a mini-split heat pump by Klimaire. Its a Chinese made product with a Japanese compressor. It's been operating for eight years and I like it. In hindsight, I should have gone one size bigger though.

When I bought mine from Florida, they were on sale and I think it was around $1700 shipped for a 24,000btu model.

Like Sparky says in post #9, the inverter types are really nice. Both indoor and outdoor units are so quiet its more like a cat purring!

Stepside
12-02-2018, 07:48 PM
Ohio Mike

Kirkland is a suburb of Seattle, so few really cold or hot days.

Ohio Mike
12-02-2018, 08:35 PM
Ohio Mike

Kirkland is a suburb of Seattle, so few really cold or hot days.

Sounds like a good place for a split since its mild.

There is a company selling DIY capable split systems called "Mr Cool"

Tim Clarke
12-02-2018, 10:18 PM
Yup, go for it. Finished mine about 3 weeks ago, so far I like it. The wall register didn't seem to be a good choice for me, so I got one of the new ceiling units. My shop is about 16x35, and I got a 12,000btu. It's well sealed, and well insulated. The wireless programmable thermostat allows me to have good control of the system, but allows a "hold" setting. We'll have to see how it works in extreme temps, but in the willamette valley in Oregon, that's pretty rare. Not all that different than Kirkland. If you have a local contractor who's willing to do the purge, evacuate and charge, thereby enabling warranty, you can do some/most of the work yourself, and buy your units on the internet. I opted to use a local company, but did some of the work myself. This was already done when they came to look over the job, and so they could see what they had to deal with.

lakeside53
12-02-2018, 10:30 PM
At 40-45F outside you can get about 3X the btu in comparison to pure electrical heat. At 20F... not great (no matter what they advertise). You can put in a dual gas/heat pump thermostat that will switch between gas and heat pump based on cost differentials. In your area (like mine) The switch over is about 35F for natural gas; not sure what it is for propane, likely lower as it cost more. At 50-55fF like we have a lot all year you are laughing all the way to the bank.

Personally... I like LG and Mitsubishi. Different scale, but I just put in a 30 ton Mitsubishi unit at work, and another 10 years ago. Nice. I also have several other units 1 to 2.5 ton (12000 btu per ton). Pretty much flawless operation with some minimal maintenance.

Mr-Mike
12-02-2018, 11:35 PM
No brainer. https://www.ecomfort.com/Mitsubishi-MZ-FH18NA/p57453.html

Sparky_NY
12-03-2018, 05:02 AM
At 40-45F outside you can get about 3X the btu in comparison to pure electrical heat. At 20F... not great (no matter what they advertise). You can put in a dual gas/heat pump thermostat that will switch between gas and heat pump based on cost differentials. In your area (like mine) The switch over is about 35F for natural gas; not sure what it is for propane, likely lower as it cost more. At 50-55fF like we have a lot all year you are laughing all the way to the bank.

Personally... I like LG and Mitsubishi. Different scale, but I just put in a 30 ton Mitsubishi unit at work, and another 10 years ago. Nice. I also have several other units 1 to 2.5 ton (12000 btu per ton). Pretty much flawless operation with some minimal maintenance.

Retired from the HVAC business a couple years ago and installed many mini split heat pumps. The new inverter tech units ARE GREATl at low temps. 20 degrees is still at full rated BTU output.

Here is a spec from one which I have personally seen in the real world several times.

"Low or negative ambient temperatures don't bother the MUZ-FH18NA2. It is rated for 100% heating capacity at 5 degrees F and 73% at -13 degrees F."

BobinOK
12-03-2018, 05:29 AM
My office is a 24 X 18 out building, insulated and paneled. I found a window unit on close out at Lowes that had electric heat for I'm thinking about $300.00, don't remember the BTU but it was enough for the square footage. I cut a hole in one wall framed it with additional 2X4s and installed a 220 outlet. It does a great job both in summer and winter and I am in Oklahoma, sub 0 in winter to over 100 in summer for days. Been running for 14 years 24/7. When it dies I'll replace it with something just like it. Have no idea what it costs to run, on the same meter as the house but doubt it would be much more than a $2000.00 + heat pump and I can buy at least 3 replacements for what one of the split units would cost.

3 Phase Lightbulb
12-03-2018, 10:22 AM
My shop is 26x42 and I heat it with a horz vented Mr. Heater 80K BTU propane + ceiling fans to help circulate the hot air and it's absolutely wonderful in the winter time. If I leave the heat off it will drop down to ~40 and I can heat it up to ~65 in around 15-20 minutes. I haven't needed A/C yet

lakeside53
12-03-2018, 10:32 PM
Retired from the HVAC business a couple years ago and installed many mini split heat pumps. The new inverter tech units ARE GREATl at low temps. 20 degrees is still at full rated BTU output.

Here is a spec from one which I have personally seen in the real world several times.

"Low or negative ambient temperatures don't bother the MUZ-FH18NA2. It is rated for 100% heating capacity at 5 degrees F and 73% at -13 degrees F."

I get that, but efficiency falls and at some outside temperature point you might as well be using gas again. Dual units (gas and heat pump) are common here with programmed switch over based on the relative fuel prices.

MikeH
12-03-2018, 10:53 PM
I installed a 4 unit system in my house last year, with the help of a friend in the HVAC trade. 36000 btu total. 4 interior units, 1 exterior unit. It heated with no problem even when the outdoor temps got into the teens, last winter. It also cut my electric bill in half! Once i get my shop insulated, i plan on putting one in there too.

Go for it, you will love it.

3 Phase Lightbulb
12-04-2018, 09:28 AM
I installed a 4 unit system in my house last year, with the help of a friend in the HVAC trade. 36000 btu total. 4 interior units, 1 exterior unit. It heated with no problem even when the outdoor temps got into the teens, last winter. It also cut my electric bill in half! Once i get my shop insulated, i plan on putting one in there too.

Go for it, you will love it.

You live in South Carolina? So when you say temps got into the teens, you mean like 13C-19C? :)

Sparky_NY
12-04-2018, 09:41 AM
You live in South Carolina? So when you say temps got into the teens, you mean like 13C-19C? :)

Evening temps during winter are commonly in the 30's F Occasional low 20's although rare do occur. Heat pumps are the most common form of heat here.

Skipped Geography classes huh?

(I'm about 30 miles from MikeH in SC)

MikeH
12-04-2018, 11:54 AM
13C - 19C, LOL.
As Sparky_NY said. We do occasionally get real winter temperatures. Rarely, but it happens. We had a couple nights, after I installed the system, where it got down between 17F and 19F.
This system does not have the electric backup heater (aka "Emergency Heat") that most heat pumps have. However, it had no problems keeping the house warm.

Mark Rand
12-04-2018, 03:52 PM
I've has a 12,000BTU mini-split in my 300sf workshop for the last four years. Cost 450 including delivery. Installation was simple and it controls the temperature and humidity all through the year. Outside temperatures range from about 15F to 85F in a typical year. Average power consumption is about 250W with a well insulated workshop.