Shop hvac opinions.

[Iroc-Z]

So I am in the process of designing my 50 wide x 36 deep shop. I am looking at running a home furnace with duct work so I can have central a/c in the summer. My plans were to put duct work along the back of the garage running the 50 ft distance. Anyone ever done this? Opinions?

 

[Jackfre]

First you have to test the homes duct system for operation. Is it at its optimum performance level? Likely it is not. How far from the garage is the current system? That in itself may negate any possibility of doing this well.

I do not think this is a good idea. It may put enough stress on the home system that it fails prematurely and then you find you need two systems, which I think you do anyway.

Google DOEductleakage.com and read for a while to see what is happening to your current system.

 

[WORKAHOLIC]

You said you are thinking of running " a " home furnace with ductwork. If that means a residential style furnace with it's own duct system it should work fine if it is a higher efficiency model that uses outside air for combustion; if not gas fumes could be an issue.
If you meant to extend the ductwork of the existing furnace out into the garage you would also need a return air duct (maybe not good). Without a return; every cubic foot of air you push into the garage will lower the pressure in the home and have to be replaced by hot outside air leaking past windows, doors, dryer vents, bathroom vents,etc.

 

[Ohmthis]

Irocz, this is a very good plan to get even distribution of air and heat through out the building. I do have some questions that might help us give you some more ideas. Are you going to have an open ceiling or an enclosed flat ceiling? Have you given any thoughts to the return side of the system? Do you have NG or is the plan LPG, maybe electric? Heatpump or straight AC? I would put my ducts through the center if possible and have branches come of both sides, that would give you the best distribution. The furnace can be horizontal so as to not to take up any room below. The furnace has to be at least 18" off the finished floor for fumes. Give some more insight and we can all help out.

 

[Iroc-Z]

First you have to test the homes duct system for operation. Is it at its optimum performance level? Likely it is not. How far from the garage is the current system? That in itself may negate any possibility of doing this well.

I do not think this is a good idea. It may put enough stress on the home system that it fails prematurely and then you find you need two systems, which I think you do anyway.

Google DOEductleakage.com and read for a while to see what is happening to your current system.

This a separate building that will have its own furnace and a/c unit. It will not be connected to my house in any way.

 

[Iroc-Z]

Irocz, this is a very good plan to get even distribution of air and heat through out the building. I do have some questions that might help us give you some more ideas. Are you going to have an open ceiling or an enclosed flat ceiling? Have you given any thoughts to the return side of the system? Do you have NG or is the plan LPG, maybe electric? Heatpump or straight AC? I would put my ducts through the center if possible and have branches come of both sides, that would give you the best distribution. The furnace can be horizontal so as to not to take up any room below. The furnace has to be at least 18" off the finished floor for fumes. Give some more insight and we can all help out.

-Ceiling will be flat
-Natural Gas

I like your idea of going down the center and branching out. That would get great distribution. As for the return I was just going to run a return duct along the bottom of the wall. I understand I am probably going to be less efficient. But I feel like this investment will be more efficient then just hanging a big heater in the corner.

 

[sberry]

-Ceiling will be flat
-Natural Gas

I like your idea of going down the center and branching out. That would get great distribution. As for the return I was just going to run a return duct along the bottom of the wall. I understand I am probably going to be less efficient. But I feel like this investment will be more efficient then just hanging a big heater in the corner.

Hanging a big heater in the corner is not a bad plan. They are a furnace. Blow it away from storage area to work area. My ideal would be one of those for quick recovery and a couple infareds in my work areas. Run as needed to "rosey" up. Redundant. For cooling had a bud put in a couple window units that worked good. Went to Walmarts or something and got 2 heavy 120V Fedders USA. I was impressed. I bought one, never a hiccup.

 

[Iroc-Z]

Hanging a big heater in the corner is not a bad plan. They are a furnace. Blow it away from storage area to work area. My ideal would be one of those for quick recovery and a couple infareds in my work areas. Run as needed to "rosey" up. Redundant. For cooling had a bud put in a couple window units that worked good. Went to Walmarts or something and got 2 heavy 120V Fedders USA. I was impressed. I bought one, never a hiccup.

I have a big max heater in my current garage and I want something better. I can get hvac equipment at reasonable prices.

 

[theoldwizard1]

-Ceiling will be flat
-Natural Gas

I like your idea of going down the center and branching out. That would get great distribution.

A natural gas furnace/heater is certainly the cheapest to install. You really should investigate a mini-split heat pump system with 2 interior heads and a couple of ceiling fans. More expensive to install, but you will save money in the long term.

Even if you have no interest in radiant in-floor heating, you should install 2" of foam vertically on the inside of all your footings down to about 3'. You will be surprised how much heat is lost through the floor and foundation.

I hope you are planning on 6" of wall insulation and 10-12" in the ceiling.

 

[Iroc-Z]

A natural gas furnace/heater is certainly the cheapest to install. You really should investigate a mini-split heat pump system with 2 interior heads and a couple of ceiling fans. More expensive to install, but you will save money in the long term.

Even if you have no interest in radiant in-floor heating, you should install 2" of foam vertically on the inside of all your footings down to about 3'. You will be surprised how much heat is lost through the floor and foundation.

I hope you are planning on 6" of wall insulation and 10-12" in the ceiling.

I am doing in floor heat. Also I plan on spray foam insulating the walls.

 

[Ohmthis]

Irocz is the central air for heat, cool, or both?

 

[Iroc-Z]

Both.

 

[Jackfre]

This a separate building that will have its own furnace and a/c unit. It will not be connected to my house in any way.

Ya know, I just re-read this thread this morning and what wondering how I got there.

 

[sevenzeronova]

If your having in floor heat why not have a hydro air unit air handler installed. Uses hot water coil for heat and separate dx/txv coil for cooling much cheaper than furnace.

Sent from my SM-N900V using Tapatalk

 

[raceman17]

Sorry I can't post a link to my ac install. The computers at work don't let me log on to my account so I am using my phone. But if you can look at the few posts I started I asked for some help with the duct design for my building. I heated and cooled about 2500sq ft using a 5 ton mobile home package unit. I posted pics and everything on my install. Maybe it will give you some ideas.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

 

[Ohmthis]

You can do one of two things (3 but 2 are pretty much the same) put in a horizontal furnace and a coil on or above the ceiling (above would have to have the duct work insulated). Or have a package unit (the furnace and air are packaged together) outside with duct work feeding into the building. Again the duct would have to be insulated with a weather resistant insulation. I see you using the air more than heat because of the floor heat.

 

[Iroc-Z]

Sorry I can't post a link to my ac install. The computers at work don't let me log on to my account so I am using my phone. But if you can look at the few posts I started I asked for some help with the duct design for my building. I heated and cooled about 2500sq ft using a 5 ton mobile home package unit. I posted pics and everything on my install. Maybe it will give you some ideas.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

That is exactly what I am looking to do. Let me know if you have some pics of the furnace it self.

 

[raceman17]

Here's the pic of my unit. It's a 5 ton heat pump. It's a pretty big unit. I think I got. It from ecomfort.com for around 2300$

All my spiral metal duct and grills were around 1100$ I installed everything myself. I'm sitting in the shop at a nice 68 degrees today. If you have any questions let me know know.

 

[plott hound]

i work for an hvac company and am in the same dilema for my 22'x40' shop.i have installed unit heaters and residential furnaces for our customers as well as a unit heater in my own garage.ideally in floor would be the best.in northeren climates your always gonna have a cold slab with forced air.im leaning towards infrared garage heater and a mini split for the summer.maybe someone can chime in that has an infrared garage heater installed.

 

[muncie21]

Subscribed, as I'm in a similar situation

 

[brownbagg]

thats a good idea, get a mobile home heat pump and just cut a hole in the wall