New AC - air handler length, ductless for residential

[masraum]

When we bought the house, the seller said "I used to work in AC. I've got some R22 and top it up once a year." I'm not sure if I believe him or not, but it was working last Sep, and it was not working when I kicked the AC on yesterday. I was able to get a recommendation last night via FB, the guy came out and put 9# of R22 in the system. It works now. If it lasted 9 months that would be great, but I would be very surprised.

The key is that it works now since I'm heading out to get my mom in 25 mins and we have a wedding here this weekend.

I asked the guy about an estimate to replace the system like for like (heat pump and electric heat) and also converting to propane for heat.

He said that most manufacturers don't make air handlers that will fit in the spot that ours is in (ours was installed in 1991). He said most air handlers are much longer, but that Rheem/Ruud makes systems with shorter air handlers. He primarily uses American Standard, Armstrong Air, Bryant and Mitsubishi. His recommendation was to consider going ductless. His pitch was that it was much more efficient, generator friendly (soft start compressors), easier to heat/cool in zones since you'd have multiple units.

Our air handler is 55" long, 28" wide and 25" tall not counting the duct that is attached to one end and the opening for the filter at the other end. I didn't measure the duct, but it's probably 24x26x18-ish. There's not really any room for anything else, but we could extend the wall at the filter end out to create more space. We could probably manage 24-30" extra if necessary.

So, anyone have any thoughts in general and thoughts on ductless specifically?

What

[nota]

when my a/c air handler was 1/2'' too wide to fit in the closet thru the door
I removed the outer case and put the coils and fan in the closet with out the metal case
I lined the inside walls with yoga mats for insulation and built a simple wood frame to hold it

btw fix the leaks 9# is a lot to lose

[look 171]

Originally Posted by masraum

When we bought the house, the seller said "I used to work in AC. I've got some R22 and top it up once a year." I'm not sure if I believe him or not, but it was working last Sep, and it was not working when I kicked the AC on yesterday. I was able to get a recommendation last night via FB, the guy came out and put 9# of R22 in the system. It works now. If it lasted 9 months that would be great, but I would be very surprised.

The key is that it works now since I'm heading out to get my mom in 25 mins and we have a wedding here this weekend.

I asked the guy about an estimate to replace the system like for like (heat pump and electric heat) and also converting to propane for heat.

He said that most manufacturers don't make air handlers that will fit in the spot that ours is in (ours was installed in 1991). He said most air handlers are much longer, but that Rheem/Ruud makes systems with shorter air handlers. He primarily uses American Standard, Armstrong Air, Bryant and Mitsubishi. His recommendation was to consider going ductless. His pitch was that it was much more efficient, generator friendly (soft start compressors), easier to heat/cool in zones since you'd have multiple units.

Our air handler is 55" long, 28" wide and 25" tall not counting the duct that is attached to one end and the opening for the filter at the other end. I didn't measure the duct, but it's probably 24x26x18-ish. There's not really any room for anything else, but we could extend the wall at the filter end out to create more space. We could probably manage 24-30" extra if necessary.

So, anyone have any thoughts in general and thoughts on ductless specifically?

What

He's correct to a certain extend on the ductless. Its easier to install but you get to look at the ugly outlet unit that's on the wall. Sam Sung makes a ceiling outlet vents that may work for your application if space is limited. Good thing about that is different zones can be turned on of off. Depending on the size of the house, I don't think I would not install ductless hvac only. How about installing a combo unit on top of the roof? How old are the ducts? On a big home, I always ask for two air returns.

[cabmandone]

The coils have gotten bigger with R410A. I have a difficult time believing you'll have a hard time fitting a new air handler in that space. What size unit is being installed? You should be able to access Carrier's website and find dimensions for their air handler (Bryant is Carrier in case you didn't know... so is Payne)

FWIW, Bryant offers a 39 1/2" tall compact fan coil.. Whew! That was tough!
https://www.bryant.com/en/us/products/fan-coils/fz4a/

Dimensions (inches) 22 x 19 x 39 1/2"


BTW... 9 lbs!? That baby was bone dry!! You go yourself one really good leak! A leak that big should be easy to find... like following the oil back to the Valdez.

[masraum]

Originally Posted by nota

btw fix the leaks 9# is a lot to lose

Yep, that was clear from the reaction of the AC guy that filled it.

Originally Posted by look 171

He's correct to a certain extend on the ductless. Its easier to install but you get to look at the ugly outlet unit that's on the wall. Sam Sung makes a ceiling outlet vents that may work for your application if space is limited. Good thing about that is different zones can be turned on of off. Depending on the size of the house, I don't think I would not install ductless hvac only. How about installing a combo unit on top of the roof? How old are the ducts? On a big home, I always ask for two air returns.

I can't imagine my wife being OK with the ductless due to the indoor units.
The house is quite small, 1500sqft on a 2 story, ~1000sqft down and 500sqft up.

Originally Posted by cabmando

The coils have gotten bigger with R410A. I have a difficult time believing you'll have a hard time fitting a new air handler in that space. What size unit is being installed? You should be able to access Carrier's website and find dimensions for their air handler (Bryant is Carrier in case you didn't know... so is Payne)

FWIW, Bryant offers a 39 1/2" tall compact fan coil.. Whew! That was tough!
https://www.bryant.com/en/us/products/fan-coils/fz4a/

Dimensions (inches) 22 x 19 x 39 1/2"


BTW... 9 lbs!? That baby was bone dry!! You go yourself one really good leak! A leak that big should be easy to find... like following the oil back to the Valdez.

Yep, bone dry. That's not surprising.

the current unit is a 30 year old heat pump. I can't imagine anyone wanting to fix the leaks.

We've been assuming that we'd need a new unit within a year, but were hoping to not have to do that right away. Clearly, we'll need to change our plans.

I was thinking, "really, how/why would things have gotten that much bigger," but then, I guess the new freon may be the reason.

[look 171]

Install two small systems in that house due to it being two stories. If not, install one one unit one but use mini-splits or duct less for some of the rooms usstairs to help cools the house down during the TX summer heat. Talk to installers and run your numbers. Put a mini split unit out in your workwhop

[masraum]

Originally Posted by look 171

Install two small systems in that house due to it being two stories. If not, install one one unit one but use mini-splits or duct less for some of the rooms usstairs to help cools the house down during the TX summer heat. Talk to installers and run your numbers. Put a mini split unit out in your workwhop

I could see a mini split in the workshop, but I'll have to seal it up first. Right now it's about as sealed as a colander or swiss cheese.

Interesting, I hadn't thought about dual systems. It just doesn't seem that big. I could maybe see ductless/splits upstairs.

[look 171]

I have added many mini splits units for upstairs bedroom use. A single unit just isn't as effective unless you get into auto dampers and such like a big building. Too much money for that in a res. setting. Mini splits installs are normally in the bedroom to help out in those long summer hot days. As hot air raises, its trapped near the highest part of the house and it radiates back into the living area burning us to death. One way is to install small vents or fans to pull air out of the highest point of the house. No weak AC system is going to win that battle. So, installing mini splits help with that task. Its normally about 3-3500 bucks for a single unit, add another 1000 bucks for two air outlets. Still the hallway will be hot. I like that only one room can be turned on for the night while the rest of the house is off saving enegry and program it to come on before sun up.

Run your numbers and see what benefits you.

[red-beard]

How many tons AC? I just had both of my units replaced including gas furnaces for $12K, 17 SEER, RHEEM, 2 Stage system.

The advantage of the ductless systems is you can install them anywhere. But...they do not help with air quality (dust removal, etc.). And they can be far more efficient than 17 SEER.

[red-beard]

In the mean time...if you need more "cooling fluid" I might have some...

[cabmandone]

Steve,
With a leak that big it should be obvious where it's coming from. My system is 25 years old. A system doesn't miraculously develop leaks unless there are factors like sulfur that causes corrosion or an object piercing the outdoor coil like a stone from a lawnmower. A common leak point that gets overlooked is the schrader valve. I had one leak like a sieve on my parent's system. BTW their system is almost 30 years old too. It's not the age, it's the tech not looking for the cause of the leak.

[rfuerst911sc]

I have a mini split in my two car man cave garage , the garage is 24x26 with 12' high ceiling and is well insulated . The mini split does a fantastic job heating and cooling the space and is a miser of electricity .

A little over a year ago I had our homes system replaced . I went with an 18 SEER Goodman dual fuel heat pump system . So it is traditional AC but depending on outside temp's heats either as a heat pump or switches over to LP furnace. The system installed was $8500.00 and has a 10 year warranty and lifetime warranty on certain items .

Since the install we have tracked electric useage vs previous year and we are consistently 40.00 - 50.00 LESS per month . Previous system was a Rheem installed in 1996 . We are very happy with the performance of the Goodman . But all brands are similar in performance/quality and ALL need to be installed correctly . Seems like an obvious statement but there are a lot of HVAC hacks out there . Choose wisely .

[masraum]

Lots of good info, folks. Thanks.

Red-B, thanks. If it gets to that, I'll let you know. I don't know about charging AC, but how hard could it be, especially with the help of the board and the Internet.

Regarding finding the leak. I'd find the leak, and then if it was something like a Schader valve, that would, presumably, be an easy fix. I assume I'd have to let the system leak down to nothing before I could "repair" any issues, though.

[billybek]

Here, it is illegal to top up without repairing the leak. Yes, 9 lbs is a lot and I bet it wasn't cheap...

Do a little research on different manufacturers AHU size. Furnaces have actually gotten shorter which is a pain when you are changing them out due to sheet metal changes and plenum adaptors. It might also be a great time to consider running two AHUs for zoning. Doing a mini split up for the upper floors and reducing the size of the central a/c might also be a consideration.

R410a phase out is to begin in 3 years but it should be available for another 10 after that for residential service. Not sure what new cocktail of refrigerant will be taking 410s place or if a conversion is possible.

[cabmandone]

Originally Posted by masraum

Lots of good info, folks. Thanks.

Red-B, thanks. If it gets to that, I'll let you know. I don't know about charging AC, but how hard could it be, especially with the help of the board and the Internet.

Regarding finding the leak. I'd find the leak, and then if it was something like a Schader valve, that would, presumably, be an easy fix. I assume I'd have to let the system leak down to nothing before I could "repair" any issues, though.

You could pump the unit down which just requires you to close the valve on the discharge line, leave the suction line open, manually depress the contactor with a GOOD INSULATED screwdriver, and pull all the refrigerant back into the system through the suction line. Then you close the suction line. The bigger issue would be needing a vacuum pump and gauges to put the system into a vacuum after repairing the schrader valve.

As far as charging goes, gauges and a tank of refrigerant. Add refrigerant slowly until you see the suction line start to sweat on the outdoor unit. Once you've got condensation on the suction line, you're "good enough"

[Zeke]

There is a tool available to change the Schrader valve while under pressure if that is the issue. Another way is to buy metal caps with sealing rings. It's a good back up as well. I throw away the plastic ones.

[Baz]

I ran into an AC guy yesterday and he said there was a new system just like the traditional one (outside condenser/inside air handler) but it was more like a mini-split.

I didn't find out anything more, unfortunately, and don't know what he meant by that. But being in the business maybe he's on to something (?)

That said - I've always like the concept of ductless-mini-split and may end up with something like that when the times comes. My Goodman is still going strong for now.....

[Baz]

Originally Posted by Zeke

There is a tool available to change the Schrader valve while under pressure if that is the issue. Another way is to buy metal caps with sealing rings. It's a good back up as well. I throw away the plastic ones.

This is correct. I bought one for use with my Silverado, but ended up not needed it. Turned out my leak was the little o-ring under the pressure switch (or whatever it's called).

[red-beard]

Originally Posted by Baz

I ran into an AC guy yesterday and he said there was a new system just like the traditional one (outside condenser/inside air handler) but it was more like a mini-split.

I didn't find out anything more, unfortunately, and don't know what he meant by that. But being in the business maybe he's on to something (?)

That said - I've always like the concept of ductless-mini-split and may end up with something like that when the times comes. My Goodman is still going strong for now.....

That is a variable speed drive HVAC system. Instead of one or two speeds, you have somewhere between 10 settings and an infinite number. The air handler also needs this speed control.

These have been around for a long time, but they are more expensive than "traditional" single speed units. They also require more labor to install and setup.

The positive: Much lower energy consumption, lower noise and typically are heatpumps.

The Negative: Cost

If you are replacing a DEAD Air Conditioner, you'll have to price the energy savings against the "cheapest" unit. My 17 SEER units were $2K more expensive than two 15 SEER single speed units. They have humidity control, which allows you to run a higher house temp than a single speed unit. And they are more efficient. The VSD units were about $10K (double) more than the 15 SEER units! Hard to justify from an energy savings standpoint when I pay $0.089/kWh.

My yearly electric costs this year should be around $2400. Half of that is Air Conditioning. Savings vs Single speed is around $200-300/year. They will pay for themselves in the life of the units (15-20 years). A 22 SEER VSP will save ~$600-750/year. Enough to pay for the difference, but initial cost is still $20K.

FYI - My Air Conditioner runs in every single month in the year! Yes, there are days in January and February where is will be sunny and 75-80F.

[Baz]

Originally Posted by red-beard

That is a variable speed drive HVAC system. -snip-

James - thanks for the clarification and additional comments. Makes perfect sense.

I have natural gas here for my furnace only - and have my meter shut off during the warm season (usually April-Dec) just so I don't get the monthly service charge. I pay a fee to get it turned back on but it's justifiable.

On the decision to get a new system - I'm looking more into a mini-split with maybe a couple registers. I have a 2/2 single story home with open floor plan so kinda a no-brainer for one of those.

Thanks again for your comments - you always add value to these kinds of discussions.