Hangar HVAC

[HRM]

On St. Pats day we'll have been here in coastal NC for exactly one year. I wanted to experience the weather over the four seasons before deciding on how to control the weather inside my 2000 sf hangar. As spring approaches, just opening the doors on each side makes a wonderful environment and this works great in the fall as well. Then there's Elsa to deal with starting mid-November and then Lucifer shows up in June.

What I really want to do is take the chill off during the cold months and moderate the heat in the summer. The whole building is uninsulated, just wooden framing with a pitched roof and 13' open-joist ceiling.

What I am thinking is either a package unit heat pump with one huge vent midway down one wall or a set of ductless mini-splits.

Looking for ideas now that I can get back into the hangar and it will be pleasant for another three months.

[slowflyin]

I went with a mini-split.   They run a variable speed compressor and are excellent at removing humidity.   I oversized mine and haven't had the typical "short cycle" high humidity issues you would normally have with an oversized heat pump.    No more rusty tools!   Working on my AC has become a joy.   Absolutely no buyers regrets.  FWIW I bought an off brand for about 30% of a name brand.   They come pre-charged and are simple to install.     Subsequently I've installed three more in different properties  and I've yet to have a maintenance issue.   

[carusoam]

What is the chance of getting insulation..?

In NJ, you can feel the heat radiating from the ceiling in the summer...

In the winter, the ceiling is vented to the outside... that would need to be stopped...   

My hangar would be a challenge economically to heat or cool...

PP thoughts only...

-a-

[orionflt]

I have the same system he currently has, it’s great in the spring and fall. But in summer it doesn’t cool enough and in winter it cools too much!!

[HRM]

4 hours ago, carusoam said:

What is the chance of getting insulation..?

In NJ, you can feel the heat radiating from the ceiling in the summer...

In the winter, the ceiling is vented to the outside... that would need to be stopped...   

My hangar would be a challenge economically to heat or cool...

PP thoughts only...

-a-

I am kicking that around. Some of the other hangars on the field are not hangars at all, but what I call aircraft showrooms. They are completely drywalled, polished, epoxied floor, HVAC, Big Ass Fan, bathrooms, bar, etc. Frankly, I sort of like the industrial look to mine and I just want the six months of high heat and bitter cold to be mitigated somewhat. I don't want to dump a huge amount of money in, just have more time to play with my toys year-round.

Because of the mild NC seasonal cycles, the heat/cold cycling is actually advantageous. If I go to the hangar in the morning during the summer and in the afternoon during the winter, my season is extended and this makes me think a hefty unit won't have any trouble at all extending that year round.

[bradp]

Hey HRM - definitely insulate first.  Then you’ll have your choice of by which means you want to control the environment more effectively and efficiently.  
 

We’re looking at doing the same for our garage a little up the road here.  It’s wonderful and we spend lots of time in the spring/fall doing projects or the kids playing in there (I have a workshop in the garage), but come winter or summer, we don’t spend nearly as much time as we’d like doing stuff because of the Elsa / Lucifer effect.  We’ll probably end up better insulating it (doors, floor and ceiling need it), and doing a ductless split unit. The insulation will probably save on the heating and AC losses for the finished upstairs over that garage a bit.  
 

Also - the giant harbor freight industrial fan works awesome to get air circulating and really does help in the summer.  

[Jim M]

Hi Brad P:

 

I noticed earlier you mentioned you had the drawing/spec for the (Piper PA32) trim switch.  One of the relay-switches is bad which is alot cheaper than the $400 (used) replacement.  Do you happen to have that P/n or drawing handy?

trim switch : 58- 862 D * SWITCH - Manual electric trim (1C670)

thanks,

Jim M

[Jim M]

typo: 587-862 D * SWITCH - Manual electric trim (1C670)

[carusoam]

Paging @bradp question for you above...

-a-

[bradp]

@Jim M

is this what you need? Removed working.  

[Jim M]

Hi Brad,

Yes, this is the switch I removed.  One of the micro-switches in the stack is bad ( I tested the others manually) so It would be great if I could order a replacement from digikey if the part number is listed? 

Of course, none of the shops have the assembly available when I called :-) .

what's the going rate for this assembly?

thanks,

Jim

[1964-M20E]

Without insulation HVAC is a daunting task.  It can be done but you will need much larger system.  

[A64Pilot]

 A few in my neighborhood have installed HVAC, and has been said without insulation it’s not going to do much good, the R rating for concrete block for instance is about 1. a house wall is about 14?

Having said that I have a dehumidifier running in my hanger as we speak. it’s 3,000 sq ft with a 14’ ceiling and really does make a difference, it pulls about 5 gls of water a day out of the air.

‘This summer when and if funds allow I’ll install a DIY two ton mini split, it won’t really cool the hanger, but it ought to dehumidify.

‘My hanger ceiling is sheetrocked, and the “mud” from the taping is falling off, from the humidity, and you know if it’s humid enough for that, it’s humid enough for corrosion. The dehumidifier stopped the mud from falling 

The 70 pint dehumidifier costs about $2 a day to operate, if it runs 24/7 which it doesn’t, you can set the relative humidity that it turns off at.

750W x 24 = 18KWH a day x .11c a KWH = $1.98 a day

Edited March 7, 2021 by A64Pilot

[0TreeLemur]

2 hours ago, 1964-M20E said:

Without insulation HVAC is a daunting task.  It can be done but you will need much larger system.  

Dehumidification is the key.   Local dew point reduction inside the hangar, and cooling the air inside the hangar so that it is "cool enough" but not cooler than the outside air dew point.   Get the R.H. in your hangar down below 40%, at an air temperature no less than say 80F for those steamy summer months.  Do that and you'll have done the best you can do.   Fans will keep it feeling comfortable when you are in there.   Man, I wish I could do this but I'm in a big uninsulated common hangar with 11 other a/c.

Insulation will greatly reduce the sensible heat load on your system.   Dehumidification normally creates sensible heat, adding to the amount of heat that you must pump out of your hangar.  So, designing such a system is, well, complicated.

If you cool the air temperature in your hangar below the outside air dew point, you are asking for trouble in two ways.   First, your hangar will be come a dew machine, especially where not or poorly insulated and anyplace where air leaks in (e.g. door).   Second, your aircraft will become a dew machine when you take it out to fly.   Takeoff quickly and now you've got moist air flow inside your cool aircraft and condensation everywhere- on the tubular steel frame, inside the wings, throughout the fuselage.

[spistora]

23 minutes ago, A64Pilot said:

 A few in my neighborhood have installed HVAC, and has been said without insulation it’s not going to do much good, the R rating for concrete block for instance is about 1. a house wall is about 14?

Having said that I have a dehumidifier running in my hanger as we speak. it’s 3,000 sq ft with a 14’ ceiling and really does make a difference, it pulls about 5 gls of water a day out of the air.

‘This summer when and if funds allow I’ll install a DIY two ton mini split, it won’t really cool the hanger, but it ought to dehumidify.

‘My hanger ceiling is sheetrocked, and the “mud” from the taping is falling off, from the humidity, and you know if it’s humid enough for that, it’s humid enough for corrosion. The dehumidifier stopped the mud from falling 

The 70 pint dehumidifier costs about $2 a day to operate, if it runs 24/7 which it doesn’t, you can set the relative humidity that it turns off at.

750W x 24 = 18KWH a day x .11c a KWH = $1.98 a day

What dehumidifier do you have?

 

[A64Pilot]

I’m not sure something from amazon, just looked it up it’s unavailable.

‘It’s actually a 50 pint and I bought it in 2016 to put in our boat, since then they are rated differently now so my 50 is likely a 30 now.’

But you can get a 70 for about $300, be sure to get one that you can connect a hose to or the internal bucket will fill up twice a day.

‘If needed there are some with pumps that can pump uphill, I just drilled a hole in the wall and ran the drain hose out that way.

The 50 is working for me, but a 70 would work better