[Small, Portable, and Ductless Air Conditioners]

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Spirit Rider
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by Spirit Rider » Wed Jul 11, 2018 9:05 am

I don't think I have ever heard of a ground source retrofit where there wasn't already existing ductwork.

The only one I am familiar with was as suggested by Alf 101: This was essentially drilling a well with a sufficient flow rate.

They had major hassles getting federal and state regulatory approval for the water discharge even though they had a water drainage easement 50ft. from their house.

pshonore
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by pshonore » Wed Jul 11, 2018 9:58 am

Spirit Rider wrote:
Wed Jul 11, 2018 9:05 am
I don't think I have ever heard of a ground source retrofit where there wasn't already existing ductwork.

The only one I am familiar with was as suggested by Alf 101: This was essentially drilling a well with a sufficient flow rate.

They had major hassles getting federal and state regulatory approval for the water discharge even though they had a water drainage easement 50ft. from their house.
Sounds like an "open loop" pump and dump system. There are also closed loop systems.

http://www.geothermalgenius.org/how-it- ... op-fields/

VaR
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by VaR » Wed Jul 11, 2018 11:33 am

Alf 101 wrote:
Wed Jul 11, 2018 8:46 am
Also, with an oil furnace and baseboard heat, I fear this might also require great rework inside the house to make it functional.
Wait, you have an oil furnace? In your original post you said you only had baseboard heat. Electric resistance baseboard heat would be wildly expensive to run in your climate zone, this is what made me wonder if switching it out would be cost effective.

So do you have electric resistance baseboard heat or do you have a oil-filled or hydronic baseboard heating with an oil furnace? This might mean that I have a fundamental misunderstanding of your situation.

Alf 101
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by Alf 101 » Wed Jul 11, 2018 1:00 pm

My error. It is an oil furnace with hydronic baseboard heat. This is a new one to me -- up to now everywhere I lived had natural gas.

I'll have to go back and check what our average fuel costs are per month over the winter. I did talk last night to a HVAC contractor, who I was able to connect up with through a personal connection. He said that he installed a Fujitsu mini-split system for his 2400 sq. ft house. He said the average cost to cool the house during the summer was about $30/month. As for heating, he said he could run it into the shoulder season -- depending on the year maybe into the first days of December, and firing back up in early March. He quoted the price of heating during this late fall/early spring period amounted to about $60/month extra on average in the electric bill. Of course he was trying to sell me something, but if true, the ROI may take some time. Still our realtor was very convinced this was a feature that added to the value of a home when selling it.

More to come...

VaR
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by VaR » Wed Jul 11, 2018 3:18 pm

Alf 101 wrote:
Wed Jul 11, 2018 1:00 pm
My error. It is an oil furnace with hydronic baseboard heat. This is a new one to me -- up to now everywhere I lived had natural gas.

I'll have to go back and check what our average fuel costs are per month over the winter. I did talk last night to a HVAC contractor, who I was able to connect up with through a personal connection. He said that he installed a Fujitsu mini-split system for his 2400 sq. ft house. He said the average cost to cool the house during the summer was about $30/month. As for heating, he said he could run it into the shoulder season -- depending on the year maybe into the first days of December, and firing back up in early March. He quoted the price of heating during this late fall/early spring period amounted to about $60/month extra on average in the electric bill. Of course he was trying to sell me something, but if true, the ROI may take some time. Still our realtor was very convinced this was a feature that added to the value of a home when selling it.

More to come...
A ballpark estimate for the shoulder season savings of a heat pump over heating oil is 40% - but only for the months that the heat pump can operate, so say down to 0 F for Mitsubishi but I'd see if you can get some better estimates of heat pump efficiency under the 17 F that I was able to find.

A geothermal heat pump will net you 65% savings the entire winter and some summer savings as well. But as you said, the upfront cost will be high since you don't have an existing forced air setup. Too bad they don't have ductless geothermal. (Actually, I think they might but it seems very specialized)

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TheGreyingDuke
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by TheGreyingDuke » Tue Sep 25, 2018 7:32 am

1) If you go ahead with the minisplit option make sure that you get one of the "cold climate" units. Those that we see in southern Asia are cheap and do not perform under about 30 degrees F to heat.

2) If you have oil heat you should have someone fo an analysis to see if you will save money by relying on the minisplit for your heat for much of the year. Here in Upstate NY electricity is relatively affordable ($.12 kWh) and oil is not. For those of us with natural gas, the equation is quite different.

I am working as a volunteer on a project sponsored by the Cornell Cooperative Extension that helps people make good decisions about these matters.

http://www.solartompkins.org/news/signs ... e-benefits
"Every time I see an adult on a bicycle, I no longer despair for the future of the human race." H.G. Wells

PinotGris
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by PinotGris » Sat Oct 06, 2018 7:37 pm

Wonder if the OP decided to go with the mini-split installation or not.
We are getting estimates for a mitsubishi. It looks like it will two condensers and 4 units.
I wonder how it looks outside on the siding with all the conduits running. I have been googling a few images but there are not many outside, only interiors.
And if you need to paint or wash or install new siding what happens?

VaR
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by VaR » Sun Oct 07, 2018 12:18 am

PinotGris wrote:
Sat Oct 06, 2018 7:37 pm
Wonder if the OP decided to go with the mini-split installation or not.
We are getting estimates for a mitsubishi. It looks like it will two condensers and 4 units.
I wonder how it looks outside on the siding with all the conduits running. I have been googling a few images but there are not many outside, only interiors.
And if you need to paint or wash or install new siding what happens?
Use Google image search with the following search terms (without quotes), "mitsubishi line-set cover".

Basically, it they look like plastic rain gutter downspouts.

mouses
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by mouses » Sun Oct 07, 2018 6:42 am

28fe6 wrote:
Mon Jul 02, 2018 5:08 pm
I'm having this exact problem about my garage, which in NC summer is uninhabitable. I only need to reduce the temperature and humidity to non-sauna levels. I don't need it fully climate controlled, and weighing my options.

Mini split: best end result, most efficient, only require 3" hole through the house to install. Downside: nobody locally will install one. It drives me crazy because these things are a dime a dozen in Japan, but it's not part of the HVAC culture thing here. So I don't know if the codes or HOA would approve for the same reason...they aren't familiar. They have DIY options mini split options for about $1000 that I could stealth-install and get away with until I sell the house at least.

Window unit: not permanent; would do the trick for cooling. Downside: need to install a window first which adds $$. Probably not HOA approved, but it's not permanent at least, and a window isn't going to hurt house value. I figure $200 for the window and $400 for the unit. So not that much cheaper...

Portable: I just don't have confidence they work very well. I could vent through my garage wall or install a window to vent it through and HOA would be none the wiser.

I'm leaning towards installing a window first, then putting in a window unit and if the HOA ding me, I'll fall back to a portable vented through the same window. If I were more confident in staying in this house for a long time I would install a split system.
Reading other posts, it seems that you don't need a window for a window unit, they can be placed through the wall, although I don't know how the cost compares.

I also have an oven-like garage, and have been wondering about things like a ceiling fan with both doors open.

Spirit Rider
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by Spirit Rider » Sun Oct 07, 2018 8:20 am

mouses wrote:
Sun Oct 07, 2018 6:42 am
Reading other posts, it seems that you don't need a window for a window unit, they can be placed through the wall, although I don't know how the cost compares.
This is not correct.

Window units are designed such that a significant portion extends outside for heat dissipation.

Thru-the-wall units may look similar, but are specifically designed to operate efficiently when installed directly thru a wall.

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Ged
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Re: [Small, Portable, and Ductless Air Conditioners]

Post by Ged » Sun Oct 07, 2018 8:50 am

28fe6 wrote:
Mon Jul 02, 2018 5:08 pm
Mini split: best end result, most efficient, only require 3" hole through the house to install. Downside: nobody locally will install one.
I wouldn't give up on the minisplit for your garage. I put a Mitsubishi in mine along with attic insulation here in southern NJ and it has been a glorious improvement. Have you tried calling Mitsubishi or checking their list for installers? There are many small businesses around here that use them.

Here's Mitsubishi's contractor finder:

https://www.mitsubishicomfort.com/get-s ... ontractors

If I had a house that didn't have air ducts I wouldn't hesitate now that I've lived with one for a few years.

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