HVAC consideration upright location - no room in attic

7 Replies

Hello fellow knowledgeable BPers-

I have just had to replace entire HVAC unit due to mold.  I bought my upstairs, downstairs duplex last year.  The HVAC system was laying on its side underneath the house and moisture, flooding, humid Texas environment really did it in.  There are no considerations inside the downstairs unit.  It is not feasible to place it upstairs in this 1914 house.  I was discussing space requirements just now with the installation crew.  I will be building out my back of house and adding a laundry room addition on the back of the house.  We discussed moving the HVAC out to the corner of the new room.  I was told last night that I would need at least 14 feet to clear the unit in an upright corner and a 3' by 3' space.  I am not sure if this is best placement or if it could lay on it's side at the ceiling of laundry room.  Nothing currently exists and I haven't spoken to contractors.  I may have a 5 foot by 13 foot area to build out in a rectangle.  I could also add a corner just for the HVAC area off of the laundry room dimensions.  It needs to be contained in doors in a humid environment.  I know I will need additional ventilation in the room as well.  Is this the best placement or could it be on its side and have the ducts run underneath the house?  I am brainstorming right now until I find someone qualified to do the work.  I will make them call the installation crew with the company as I have already purchased the entire system replacement.  I am just waiting to get the room built for placement and they will come back and move the location of it from under the house.  This is gas and a furnace as well.  I know I will need water, gas, and new electric ran to supply it.  Any ideas or additional considerations would be greatly appreciated. 

@Kristy Farmer is it too late to get a refund and install a ductless heat pump? Either way, this isn’t a project for even the most ambitious DIYer. You’ll need an experienced installer to tell you what your options are.

Some ac handler units are Made to be installed horizontally, on their side, you can’t install one made to be vertical on its’s side.....the interior condensation pan/drain line configuration are designed differently. Not sure what mean by needing 14’ ?

@Kristy Farmer Sounds like spending a bunch of money for nothing? Just leave it under the house..instead of using the very costly Trane unit I would use the cheapest no name brand..if it blows up in 8 years who cares? Just replace it again..build the cost into your capx budget.. Seems wiser than dumping 20k-30k to rearrange everything?

@Wayne Brooks :  Thanks for that.  Yes; I also found out last night that the coil in the one they installed is meant to be horizontal and not the v coil he spoke about.  I will call today and discuss this with them as they will have to exchange that unit.  He spoke about needing 14 feet for the plenum and furnace along with ducts to be positioned vertically.   I have a very small yard and there is no room for a horizontal direction.

@Mark Fries : Why would it cost 20 to 30 K? I didn't anticipate that cost for this unfinished laundry room? I know how much the plumbing, electrical, and gas would be as I just redid a bathroom in this house. I am moving it because it is the best way to deal with this situation long-term. I am living here and was sick for the past couple of months. I have already determined where the laundry sits in the house is where I will add the half bathroom, which is the reason for adding a laundry room. These plans were already here to get my 20% equity, refinance, and reuse the FHA program. So that's where I'm coming from with this project. I do have to speak to someone in construction that is familiar with HVAC installation requirements, and this will require permits for the work.

@Noah Jones : Yes; I'm definitely aware that I'm not touching it or dealing with a small job.  I don't think it's better to get each specialty (electric, plumbing/gas) over here on this one.  I won't probably be playing the GC role on this one because I need it done properly.  They will call the company back and discuss needs before it's started construction as well.