HVAC recommendations

[nhraracer90]

Hello! I have a 2600 sq ft building w/ 14ft ceilings. It’s well insulated and so are the garage doors. I have some questions on what possible systems to get.

Self contained unit: I know this unit will sit outside and you just run the duct work right inside. It would be gas heat/ac. What are the pros and cons of this type of unit?

Split unit (air handler inside and unit outside like a house): this would be gas heat/ac as well but I know part of the unit would have to be inside so it would take up floor space or I’d have to build something for it to sit on.

Gas furnace heat only: this would be a propane furnace with heat only. I know this would be the cheapest option and would be inside as well. Could AC be added to something like this later?

I don’t plan on being in there all the time so the unit won’t constantly be on. During the winter I’d maybe set the thermostat to 45 or so. I also have radiant heat in the flooring but it’s not hooked up yet and that won’t be the primary heat source

Thanks!

 

[theoldwizard1]

Mini-split heat pump

 

[PoorUB]

Hello! I have a 2600 sq ft building w/ 14ft ceilings. It’s well insulated and so are the garage doors. I have some questions on what possible systems to get.

Without more info, like electric rates, natural gas available and price, or propane it is pretty hard to say. Do you want air conditioning?

Mini splits might work fine in your area, but they are not always the inexpensive way to go. If you keep it heated all the time, have natural gas a 90+ furnace and split AC might be the way to go. Mini splits are great as they are easy to install and give great efficiencies, as long as you electrical cost is low. If you have a high KWh price they can be more expensive to operate that gas.

A self contained outdoor unit is usually less efficient than a 90+ furnace and split AC. But if you don't plan on using the AC a lot then why worry about efficiency? The cost for a more efficient unit will never get paid back in energy savings.
You usage of the shop has some bearing.


It is kind of like you coming on here and asking us which you like better, blondes, brunettes or red heads?

 

[nhraracer90]

Without more info, like electric rates, natural gas available and price, or propane it is pretty hard to say. Do you want air conditioning?

Mini splits might work fine in your area, but they are not always the inexpensive way to go. If you keep it heated all the time, have natural gas a 90+ furnace and split AC might be the way to go. Mini splits are great as they are easy to install and give great efficiencies, as long as you electrical cost is low. If you have a high KWh price they can be more expensive to operate that gas.

A self contained outdoor unit is usually less efficient than a 90+ furnace and split AC. But if you don't plan on using the AC a lot then why worry about efficiency? The cost for a more efficient unit will never get paid back in energy savings.
You usage of the shop has some bearing.


It is kind of like you coming on here and asking us which you like better, blondes, brunettes or red heads?

I live in WV and do not have NG so it would be propane. I would like to have AC yes. I know if I got those mini splits I’d probably need 3-4 of them placed throughout the shop. I know I would also have to run duct work for anything else. My shop is a 40x74.

 

[danski0224]

Did you have a load calculation done?

You could need anything from 20 to 300,000 btu....

 

[nhraracer90]

Did you have a load calculation done?

You could need anything from 20 to 300,000 btu....

Not yet. I’m more just looking to see what everyone’s opinions are on the difference types of systems. Of course I’ll have someone actually come figure out the correct unit size when I decide to get one

 

[danski0224]

If you are considering a heat pump, you will need to know what the building load is to figure out the thermal balance point.

Utility costs will be needed to figure out the economic balance point.

Some of this information could drive equipment choices.

 

[nhraracer90]

If you are considering a heat pump, you will need to know what the building load is to figure out the thermal balance point.

Utility costs will be needed to figure out the economic balance point.

Some of this information could drive equipment choices.

Okay thank you

 

[PoorUB]

I live in WV and do not have NG so it would be propane. I would like to have AC yes. I know if I got those mini splits I’d probably need 3-4 of them placed throughout the shop. I know I would also have to run duct work for anything else. My shop is a 40x74.

Propane versus electric on most areas is a toss up. Propane prices can vary with the wind, but then I would bet on the east coast your electric rates are close to 20 cents per KWh too. Do you have your electric rates and LPG prices?

A "normally" insulated shop can be heated and cooled with 30 BTU per square foot, and I am talking North Dakota were we see -30F and once in a while -40F in the winter and sometimes 100F in the summer.

Mini splits are good, as long as you don't have issues with them. They can be terribly expensive to repair out of warranty, or if the installer disappears and nobody will honor the warranty. A simple 95% gas furnace and a 14 SEER AC is about as simple as you can get. Simple as in probably needed very little service and repair over it's life time. A heat pump is probably next in line. As you increase efficiency the price for the equipment goes up along with more service and repairs down the road. Often I feel the lower efficiency equipment will be less money over all.

What is the average winter and summer temps in your area?

 

[35Ford]

Do you have a local HVAC company you trust? I'd start there.

 

[danski0224]

Okay thank you

You are essentially stuck with electric or propane for the floor heat boiler.

Can't really decide until load and estimated operating costs are figured.

Was the tubing installed properly? Who figured out the heat loss and tubing layout? Thermal barriers done right? Improper installation will kill you with operating costs.

Ground source heat pump could be an option for air heating and cooling. Comes down to cost. This is probably the only option for 100% heat pump in a heating dominant climate zone. Upfront cost is high and installation has to be right.

Solar (electric) could make "economic balance point" a non issue.

Local/State/Federal tax credits can come into play.

Insulation and building tightness is way cheaper than high dollar HVAC equipment.

 

[nhraracer90]

Propane versus electric on most areas is a toss up. Propane prices can vary with the wind, but then I would bet on the east coast your electric rates are close to 20 cents per KWh too. Do you have your electric rates and LPG prices?

A "normally" insulated shop can be heated and cooled with 30 BTU per square foot, and I am talking North Dakota were we see -30F and once in a while -40F in the winter and sometimes 100F in the summer.

Mini splits are good, as long as you don't have issues with them. They can be terribly expensive to repair out of warranty, or if the installer disappears and nobody will honor the warranty. A simple 95% gas furnace and a 14 SEER AC is about as simple as you can get. Simple as in probably needed very little service and repair over it's life time. A heat pump is probably next in line. As you increase efficiency the price for the equipment goes up along with more service and repairs down the road. Often I feel the lower efficiency equipment will be less money over all.

What is the average winter and summer temps in your area?

I don’t know the electric rates. I have a separate meter for my building and it’s a different rate then my house. Looking online current LPG prices are around 3.30-3.40 gallon. During the winter we are in the high 20’s to 30’s occasionally in the teens. During the summer low 90’s and sometimes in the low 100’s. I am use to having a oil burning furnace and have never used LPG before. Since I won’t be there full time I am fine with having something less efficient. I don’t want to pay another $2000 for a unit that’s more efficient but only saves me $10 a month in operating costs

 

[lzenglish]

1.) I suggest you find other like shops in your area, and see what works for them, as the Proof is in the Pudding. See What Works and what doesn't work for your area climate.

2.) Contact Your Local Utility Company and ask them what they recommend, and all rebates offered.
They SHOULD be happy to advise you on your options. "Energy Audit"

3.) I would play off your existing radiant heat run, and its boiler size to also help with your decision.

Knowing what i know so far, i Kinka like the forced draft NG or Propane Hanger Heater Units for Heat, coupled with Cool only Mini Split Terminals. Depending on your year round high and low temps, a mini heat pump may also work.

Just My 2-cent Spit Ball,

Good Luck,

LZ

PS: Condensing Units on the Ground Get Pissed on, and Gather Dirt and Debris.