house a/c

[thejudges69]

I've been thinking about getting some type of central air in the house. I have a single story ranch about 1100 square feet with a full basement. We use the basement all the time since it is a walk out. The issue I have is that my basement ceiling is about 76 inches high, so the big trunk in the basement is a problem. I don't want to be banging my head off of it all the time. Are there any alternatives to this install. Also, the one and only quote I got was like $5500 for the complete install which seems to me like a lot of money, but I really don't know. I'd like to have some options to go at these installation people with other then the trunk. I know the neighbor put flex hose in his 2 story house but I'm not sure if its good or bad. I am way out of my league on this so any insight is appreciated.

 

[pattenp]

You can put the air handler and ducting in the attic. Not the best option, because your air handler and ducting are fighting the attic heat. The basement is really the best place.

$5500 sounds in line.

 

[thejudges69]

my attic isn't the biggest. I can sit up there at the peak but my head is a few inches from the nails from the shingles. I'm thinking the basement is the best for this install. I just don't have space for a bunk trunk.

 

[Jackfre]

Do a search on mini-split heat pumps. Plenty of reading. Plenty of brands. I suggest sticking with the top two brands, Fujitsu and Mitsubishi. Ideal systems for retrofitting ac to a home. No ductwork and very high efficiency. As well they heat economically.

Your neighbors small tubes are known as "hi-velocity" systems. When done "just right" on the duct layout they are reasonable quiet. Mistakes in tubing will drive you crazy and they are not nearly as efficient as the mini split heat pumps.

 

[ForceFed70]

Yeah, I'd also reccomend a mini-split system. Especially if your home has an open floorplan.

Depending on your basement depth, stairway, etc you may not need to put any AC in the basement.

 

[pseudorealityx]

My problem with mini-split heat pumps is that they don't typically have any auxiliary electric strip heat in the fan coils. In an Ohio winter, you're asking for problems. There's also the eyesore of having the units mounted on the walls.

You can have them build the trunk duct out to a rough max of a 3:1 or 4:1 ration on width vs. height before you get into big problems. If you can locate the unit somewhat centrally, instead of 1 trunk that carries all the air, you can branch it both ways and have trunks going in 2 directions, carrying half the air, and therefore, smaller sizes. Flex duct is fine, but it's got a big pressure loss, so you're working the fan harder to get air from the unit to the house. You'll lose some flow compared to hard duct. You also need to pay attention when you hang it so you don't crease it up and add even more blockage.

Alternately, you can lay down air handlers horizontal in the attic. Basement is better, and I would possibly add some more insulation to the bottom side of the roof deck, but it might be the best solution for you given the low basement ceiling height.

 

[wb2vsj]

I had a 3-level split home that the HVAC guys ran some of the ducting/trunks in between the joists in the ceiling of the lower level.

 

[M-technik-3]

We have an old house with ballon framing that had no AC to the second floor nor a return. We added a return in a closet wall to get some more efficiency out of the main unit and added a mini-split to the second floor for under $1500. Was well worth it, as the cool air tends to come down from the second floor so we don't run the older unit as much now.

 

[thejudges69]

the mini split system I'm familiar with what it is. I spoke to a dealer regarding that and he said that I would be more money then a standard system and probably less efficient. He mentioned one for each bedroom and one for the kitchen and one for the living room. and then the piece that goes outside.

The a/c company said that they couldn't put the trunk in the floor joists because of the layout of my house to keep it efficient and flowing good they would need to put it on the bottom of the joists.

I think I may have to call some other companies and get prices and ideas from them. I of course called the most expensive people in the book first.

Anyone on here near youngstown want a side job haha.

 

[olytdi]

the mini split system I'm familiar with what it is. I spoke to a dealer regarding that and he said that I would be more money then a standard system and probably less efficient. He mentioned one for each bedroom and one for the kitchen and one for the living room. and then the piece that goes outside.

I think I may have to call some other companies and get prices and ideas from them. I of course called the most expensive people in the book first.

This sounds like bunk. Your house is, by many measures, small and probably would be well served by two or so units. Sounds like they weren't into it or don't know what they're doing. A lot of times, they'll just say something like that and, who knows, maybe you'll bite.

I would definitely check-in with a number of outfits experienced with split minis and re-evaluate after that.

 

[pseudorealityx]

This sounds like bunk. Your house is, by many measures, small and probably would be well served by two or so units. Sounds like they weren't into it or don't know what they're doing. A lot of times, they'll just say something like that and, who knows, maybe you'll bite.

I would definitely check-in with a number of outfits experienced with split minis and re-evaluate after that.

Doesn't sound like bunk to me. The house is small, but you want cooling in every bedroom, and depending on how open the living room/dining room/kitchen area floor plan is, having multiple units might very well be reasonable. Such is the exact problem with mini-splits for residential use.

 

[Orangestang]

Sounds like they just want to use "in stock" ductwork 8x12,8x20 etc... A good guy can size the ductwork down to 4" or 6" X __ and still get the same CFM as the 8x __, it may cost a bit more but it can be done.

 

[pseudorealityx]

Sounds like they just want to use "in stock" ductwork 8x12,8x20 etc... A good guy can size the ductwork down to 4" or 6" X __ and still get the same CFM as the 8x __, it may cost a bit more but it can be done.

It can certainly be done, but the problem is, assuming a 2 ton unit, if you bring it down to 4" tall duct, it needs to be over 4 feet wide to get the same flow, and it'll rumble. You get some big losses when you get really skinny.

Going to 8" deep duct, you could get away with 20" wide ducts, which is practical and shouldn't rumble.

 

[Falcon67]

Doesn't sound like bunk to me. The house is small, but you want cooling in every bedroom, and depending on how open the living room/dining room/kitchen area floor plan is, having multiple units might very well be reasonable. Such is the exact problem with mini-splits for residential use.

This is why we blew off minis for the old house - just not real compatible with older houses that don't have a wide open floor plan.

OP - only way you'll get it done where it works well and is economical is to sacrifice some basement head room for the ducting. An alternative may be to situate the furnace/AC under an existing closet, then give up that closet or part of it as a plenum or chase for feeding lines run in the attic. At 1100 sq/ft, I'd guess that may not be an option.

Edit - this is the one I saw when we looked at that other house
https://www.pexuniverse.com/little-giant-vcma-20ulst-condensate-removal-pump-554435

 

[Highbeam]

There's also the eyesore of having the units mounted on the walls.

Yes, and ugly they are. If these things looked less like something from an RV or some sort of window mounted ghetto AC unit then they would be much more common.

 

[pseudorealityx]

Yes, and ugly they are. If these things looked less like something from an RV or some sort of window mounted ghetto AC unit then they would be much more common.

Within the commercial world, they are now offering recessed versions. But at that point, why not just do a normal split system?

 

[Jackfre]

The contractor who said it is less efficient is, putting it plainly, a bit behind the times. The difficulty in retrofitting sheet metal to an existing house is that it is seldom done well. You therefore end up with imbalances air flows and noise.

One of the good things about the multi mshp's is you have a selection of evaporator choices. You can use the high wall evap, the ceiling cassette( which has quite a commercial look, but is a 2,3 or 4-way blow) or you can use the compact ceiling cassette. That would mount in the attic or basement and you have limitation on the amount of ductwork you can run, but...you can do 2 or 3 rooms with one evap.

On my home I put a dual unit for the upstairs 16.5 seer/I think about 10 HSPF. The bedrooms are entirely separate and the primary living area is handled by a 25 SEER/12HSPF unit. The ultimate in zone control and the max efficiency in heat.

You will likely pay a bit more for the mshp(s), but they will return the cost of the investment quicker and give you quieter and more comfortable operation, IMHO

Oh, and no you cannot add back-up heat to this system, but I assume you all ready have heat as you asked only for cooling. Leave that system in place and use it seldom. The other unit I have in my home in the foothills of the
Sierra is the Rinnai Energysavers dV wall furnace. It to is net to the space.

 

[chevelle67]

Sounds like your house is exactly why unico's were conceived. Call a contractor that is versed enough in several different types of systems and isn't just pushing the type or brand they are comfortable with. There are different types for different applications all with +'s and -'s. . Custom engineered systems come with a custom price unfortunately.

 

[brewchief]

Depending on your basement layout you may be able to run the duct work below the joist but along one wall, this will result in longer round pipe runs to some rooms and very short runs to others but it can work fine if the duct work is properly sized.

I've installed unico systems in some pretty tight attics, not fun by any means but they do work well.

Mini splits work well and are very efficient but are harder to make work well in a house without an open floor plan, nobody ever wants the evaporators mounted in a spot that is easy for the contractor.

What do you have for heat now? Do you want to keep it or completely switch over to the same system the A/C will use?

 

[thejudges69]

Right now I have baseboard oil heat, my buderus furnace is only a few years old so I'm not looking to change it again. I would really like to keep this as efficient as possible and as simple as possible. If my basement was just 1 brick higher then there wouldn't be much issue at all.

The wall units don't look to bad, there not my first choice u can assure you that. The Indie units aren't a top choice either but at the moment its the best option going til I find a suitable alternative.

Jackfre what exactly is an mshp? I'm not super familiar with this stuff, but all this is good for me when i contact some companies regarding this.

The floor plan of my house is not really that open. My house is a manufactured home on a foundation so there is a main bearing wall almost the while way down the center of the house.

 

[pseudorealityx]

MSHP is mini split heat pump.

And a Unico system is going to be anything but 'efficient'.

 

[Jackfre]

MSHP is mini split heat pump.

And a Unico system is going to be anything but 'efficient'.

As to the Unico/spacepak, the top two brands of hi-velocity cooling equipment, you are correct. They work, but are not nearly as efficient as mshp. This is due in part to the hi pressure fan systems as well as the fact that when the regs cameout a few years ago to go to a min seer of 13, there was a loophole which the hi-Vel manuf's chose to take advantage of. It was a "confined space" loophole and allowed them to stay under the 13 seer requirement that all other equipment had to make. As well, you must be spot, precisely, to get the best out of them from a noise or whistle effect of improper ductwork.

Your Buderus is an excellent oil boiler. You might want to check into a power gas burner for that boiler. I believe Riello makes the unit for Buderus. Not necessarily suggesting you change, but as long as you are in research mode, it is best to understand your options before the next big oil shock happens in the middle of the season. Do you have outdoor reset on your Buderus?