[67_LS1]

I’ve seen some other posts about HVAC and know there are some pros on this forum so I’m looking for some advice.

I’m finally breaking down and putting AC in the house. Been here 40 years and it hasn't been an issue until that last few years. Hotter weather and older age are not a good combo.

Our existing furnace (Carrier) Is pretty new so we’re going to keep it. Our house is 2 story, semi-open construction, 2400 sf, master bedroom downstairs, all other bedrooms upstairs. Currently we keep all the upstairs registers closed since no one is ever up there. Northern California location so basically zero humidity.

I can tell you that we are not AC people. We prefer open windows to AC so we will only run it when it’s over 95-100 for multiple days and the house doesn’t cool at night.

The reason I’m asking is we’re getting quotes all over the place. Not so much price all over the place but equipment. 3 ton, 4 ton, single stage, two stage, 14 SEER, 17 SEER, dual zone, left handed (just kidding on the left handed).

I understand the tons and really there isn’t much difference between 3.5 and 4 tons but what about the single vs 2 stage and the dual zoning (not an inexpensive adder)?

And one guy said it’s fine to put a lattice type fence 12” away. Another gut said a minimum of 24” all around. To an open lattice fence? Seems nuts.

They also all say “plastic pad”. Does this go right on the dirt or should a make a DG pad for the plastic pad?

Any other things I should consider before deciding?

Plus I've been quoted Carrier, Day and Night and Bryant, which I understand are all from the same company anyway. Is anyone better than the others or one to avoid?

Thanks

 

[Dean]

The biggest problem with adding air-conditioning to a two story house that was built for heat only is usually the supply and return air ductwork supplying the second floor is too small.
There is more to being comfortable in warm weather than cooling down the temperature, dehumidifying is just as important.
The only time it will be doing that is when it is running so you don't want a unit that is too big, btu/hr wise.
Most people don't realize this and think the unit should not run too long and want it to shut off, not knowing that it is just coasting so to speak, not drawing high amperage.

OH and about dehumidifying;
I takes about three days to get the humidity down when the unit is first turned on and if you shut it off and open the windows, the humidity will be back up where it was in an hour or less.

 

[shovelrick]

In Florida we're required to use a 4" thick hurricane rated 150 mph fiber cement with styrofoam on the inside pad for the condensor to sit on, this was an existing pad we reused last friday EDIT I had to dash for a min, the ac contractor should do a Manual J load calc for ac size and Manual D load calc to size the ducts to be 100% certain, I usually shoot from the hip and all's good on duct size but ac size should be calc'd, my laptop is acting up I'll be back

 

[67_LS1]

I mentioned in my OP that we have really low humidity in California. It’s never an issue. Not Arizona dry but not moist.

One of the contractors mentioned that he thought the house was originally built with AC in mind because the upstairs has only 4 registers in the ceilings and there is what appears to be a 12“ and a 8” duct from the plenum below the heater up through a chase to the attic where they each split into 2-8” ducts. All of the ducts to the upper floors are insulation wrapped flexible round.

The downstairs has 8 registers in the floors fed through rectangular metal ducts. I’m not sure of the sizes.

My daughter has a rental property near here that has a massively over sized AC unit. It’s 6 tons in a 1100 sf single family. It runs for like 3-4 minutes and shuts off because it cools the house so quick. A repairman told her that this was not good at all.

We also don’t have hurricanes or tornados. Just earthquakes. All our newborns units seem to just have pieces of rebar driven through the pad mounting holes and bent over on the top.

Also, any benefits/drawbacks to horizontal discharge condensers?

 

[shovelrick]

Another problem with ducts designed for heat is the insulation on the old ducts is too low of an R factor and will often sweat in high humidity conditions, like Fl. attics but if you live in a low humidity area maybe not a problem? zoning is what I prefer to stay away from because those boards break down, if I need to go back to replace a zone control board, 24v duct damper etc. within the 1st or 2nd year of install I get THE LOOK and feel like my customer feels they've been ripped off, 2 story home = 2 systems and I have happy customers and when they do break down they have another air conditioned floor to go to until the repair, OR 1 unit and 0 zoning just find the best location for the Tstat, as far as 14 SEER and up I install mostly 15 SEER it gets a Duke energy rebate, when you get 17+ the extra cost isn't going to be recouped in the life of the system IMHO, the squeeze isn't worth the juice so to speak, the husband & wife the own my shop/storage where my car is had me repair a 19 SEER Bryant heat pump system ( 3 in the home) it's a communicating type system, the air handler blower motor failed on 1 system the units were 6 yrs old and the installing cont. DID NOT register the equipment for the extended 5 yr warranty for a total of 10 yr. warranty, the high 19 SEER system can not use anything other than the factory replacement motor so instead of a very good universal motor it had to have a motor that cost 3 X the price and will not last any longer, then the cost of the higher SEER Tstats the are needed uhg!

 

[shovelrick]

About the fence around the unit I'll post a pic from the installation manual tomorrow, I'm a Heil dealer and it's the exact same equipment as Day & Night, under the Carrier umbrella International Comfort Products (they use to come with a Carrier sticker on the blower housing), they were going to use your existing furnace and add a case coil to it for the ac correct? oh Payne & Bryant are also made by Carrier

 

[67_LS1]

I read an installation manual for a DayandNight unit and it says 6” on one side and 12” on the other three. That’s doable where I want to locate it. It will also have a single 2x6 board passing over the top of it about 18” up. I hope thats not an issue.

The house was built in 1990 and it is insulated like crazy. When it’s 105 out in the afternoons, we’re usually ok until about the third day just keeping doors and windows closed. After that the house is just heat soaked.

 

[chasmalo]

67,

I've installed 3 different units in 2 houses I've owned in Southeast Michigan (Clinton Township) . My first house was a new single story, about 1000 square feet. Decent insulation, not the best. I put a 2 ton unit in myself. I learned how to vacuum it properly and charge it myself. My mistake was that It ran ok but it was too small. Rd Couldn't keep up on a hot day. It probably needed a 2.5 ton. (It ran constantly but couldn't keep up .It was too small It. The pump and tools were not expensive. I bought gages for the correct refrigerant, which in 1972 was R-22. As mentioned, the unit was a too small. I had to cool the house at night so it could carry a comfortable temperature throughput the day. (R22 is hard to find now.)
- Some older units use R134a which is still available.
‐ R 410 is what's in use now. - the latest refrigerant. The unit you choose is designed for a certain refrigerant. Don't try to switch them.
- You have to buy R 410 through a licensed contractor if you install it yourself or you could have a qualified person charge it for you rather than buy a vacuum pump and gage set. If you think you will use them again for others (friends, family?). Harbor Freight has good tools for reasonable prices. I use HF gages and an older Blue Point vacuum pump I picked up cheap. Works great.

• Measure the living space of your house carefully and
• Get a feel for the insulation value you have. Depending on where you live, North, South Hotter areas or cooler the unit has to be sized for all that. In other words, how much heat does the unit have to pull out of your house. I put a too-big unit in my second house. 4 tons (48,000 BTU) For a 1,950 square foot house with bad insulation. My wife didn't like AC so she kept it off during the day. When I came home from working in a hot plastic Injection molding factory I wanted to turn on the AC and have it cool the house down fast! The unit was too big. It didn't run enough. We had cool, damp air.

A right sized unit should run about about 60% of the time for proper cooling and correct dehumidifying. Much of the cooling comes from removing moisture from the air. It has to be drained properly. Run a Pipe from the AC drain to a floor drain.

Of course you need 240 volt power of sufficient size, and with proper circuit breakers or fuses to run the unit.

Good Luck! Keep us posted.

Chas

 

[shovelrick]

When you read the installation manual for clearance did it say for fence? normally the detail is for a solid wall, it's pouring down rain now but when it slows I'll get a manual from my van, Bryant & Payne are sold from the Carrier Dist. and before you can be a Carrier dealer you must sell Bryant for IIRC 5 yrs. for Carrier to see your sales volume and if it's good Boom you're a Carrier dealer (friend of mine had too many issues with warranty parts, got a little loud and Boom he's no longer a Bryant dealer) Payne is also sold at Carrier but no dealer requirement, I can buy them but rarely do, only when a customer asks for that brand, funny I can't buy a matched Carrier system but I can buy 1 part on one day and the other part the next but that might be because I've known 1 of the counter guys there 20+ yrs. Day & Night is a regional brand name the same as Heil, Comfortmaker, Tempstar is in this region, Carrier has the largest piece of the pie when it comes to A/C equipment MFG. Read warranties as they all offer 10 yrs. parts with registration and some model come with No Hassle free replacement units EDIT this is just a side note, I think Ca. is a state that requires a license for a/c contracting and also liability ins., I would watch what company you hire to be sure they have those and look online for any bad reviews, here in Fl. there's so much UN-licensed activity the Sheriffs Office set up stings and many are multiple offenders and most are no cheaper than a lic. contractor lol, also in Fl. a 1 year labor warranty for the contractor is law so if anything is wrong the first year you Should NOT be charged any $$$, lot of cont. around here screw people on that

 

[67_LS1]

The manual does look like a solid wall. The one contractor said it didn’t matter. I find that hard to believe. The lattice fence I’m proposing will be on three sides and removable in 5 minutes so service access should also be wide open. One of the AC guys has got to 6’10” and 300 lbs so he was all about service access.

The location will also be in the morning sun and afternoon/evening shade so hopefully the sun won’t be beating down on it when we need it most.

The refrigerant lines will be about 40’ long running from the furnace in the garage through the crawl space under the house to the less used side of the yard. There is about 24” clearance under the house so they’ll have to be hung from the floor joists. It’s super clean and dry under there. The 40 amp power and the control wires will be under there too.

I offered to all of the contractors to supply the breaker, pull the wires and provide them with a disconnect and 6’ whip but they all included that in there scope without a breakout so I’m assuming that was a “no“.

I’m glad you mentioned the SEER rating too because my wife wants a 26 SEER unit that was crazy more money. The only reason I liked it was a lot quieter.

 

[shovelrick]

The 15 SEER units are very quiet, read up on the sound levels, the 15 SEER units I sell also have a sound blanket on the compressor, the 15 seer unit I installed in my home has a 2 speed condensor fan motor that has a very low sound level, I'm going to take a pic of my surge protector, I highly rec. these and they cover up to $5K if there's damage due to a failure, are these contractors telling you any info about permits? most a/c contractors don't have a license to do electrical work, they're only allowed to work/wire from the service disconnect and not even allowed to install the service disco edit: I need to help my wife get ready for a dr appt. I'll post more a little later

 

[pduncan]

I cant add much to the great info you got already. Seer probably means more down there when your unit might run close to 12 months a year. For us Canucks that need them 3-4 months not so much. Someone above mentioned (Rick I think) that at some point the payback on higher seer units might not be worth the extra initial cost. And 'usually' the higher the seer, the larger the unit if space and clearances is a concern. As far as International Comfort Products goes, I was a distributor for probably 30 years. Decent product, you cant go wrong with any of the brand names you mentioned. And if you go with them, make sure the contractor registered for the extra five years parts warranty as also said above. Go to ICPUSA.com and click on product registration. It should tell you there. You can register it yourself if the contractor did not.
Good Luck.

 

[67_LS1]

The 15 SEER units are very quiet, read up on the sound levels, the 15 SEER units I sell also have a sound blanket on the compressor, the 15 seer unit I installed in my home has a 2 speed condensor fan motor that has a very low sound level, I'm going to take a pic of my surge protector, I highly rec. these and they cover up to $5K if there's damage due to a failure, are these contractors telling you any info about permits? most a/c contractors don't have a license to do electrical work, they're only allowed to work/wire from the service disconnect and not even allowed to install the service disco edit: I need to help my wife get ready for a dr appt. I'll post more a little later

One of the quotes was for a 2 speed condenser. I thought this might have has something to do with the zoning options. Is this just for efficiency/noise?

 

[shovelrick]

2 stage is compressor, it'll run on high speed until the house gets to within a certain set temp then drop down to low speed to maintain that temp, those are the communicating systems and are very eff. but cost a lot more $$ and IMO dont pay for themselves before they are worn out, most that I've seen anyway, here's a pic of my 15 seer outside heat pump unit with a 2 speed fan, I put the plastic mesh on top to keep oak leaves out and a pic of the surge arrestor that I like

 

[shovelrick]

When a house is over sized here in Fl. the problem is high humidity and a cold clammy house that gets mold very easy, the unit doesn't run long enough to remove humidity so makes a damp wet feeling causing wood or laminate flooring to warp, moldy furniture and the biggest problem is health issues

 

[68C427GO!]

67-ls1

Just for reference, been doing ac to long. Worked for that brand for many years. I guess I’m bias. Carrier is a very good brand. But like everything they come in many flavors. In your case I would recommend keep it simple. Just go with a 4 ton. 16 seer. The 4 ton will have enough capacity to give a reasonable pull down when you need it. And anything over 16 seer in your case you’ll never see a return on your investment. Put the extra money in you car 🤓

Just my .02.

 

[shovelrick]

I'd still get a Manual J load calc to get an honest tonnage size, in my region I would say a 4 to 5 ton but I'm not familiar with a dry climate, LOL I'd probably be broke

 

[Jasons 69 Chevelle]

I’ve seen some other posts about HVAC and know there are some pros on this forum so I’m looking for some advice.

I’m finally breaking down and putting AC in the house. Been here 40 years and it hasn't been an issue until that last few years. Hotter weather and older age are not a good combo.

Our existing furnace (Carrier) Is pretty new so we’re going to keep it. Our house is 2 story, semi-open construction, 2400 sf, master bedroom downstairs, all other bedrooms upstairs. Currently we keep all the upstairs registers closed since no one is ever up there. Northern California location so basically zero humidity.

I can tell you that we are not AC people. We prefer open windows to AC so we will only run it when it’s over 95-100 for multiple days and the house doesn’t cool at night.

The reason I’m asking is we’re getting quotes all over the place. Not so much price all over the place but equipment. 3 ton, 4 ton, single stage, two stage, 14 SEER, 17 SEER, dual zone, left handed (just kidding on the left handed).

I understand the tons and really there isn’t much difference between 3.5 and 4 tons but what about the single vs 2 stage and the dual zoning (not an inexpensive adder)?

And one guy said it’s fine to put a lattice type fence 12” away. Another gut said a minimum of 24” all around. To an open lattice fence? Seems nuts.

They also all say “plastic pad”. Does this go right on the dirt or should a make a DG pad for the plastic pad?

Any other things I should consider before deciding?

Plus I've been quoted Carrier, Day and Night and Bryant, which I understand are all from the same company anyway. Is anyone better than the others or one to avoid?

Thanks

I would quote 2 systems 1 upstairs 1 downstairs.
2 stage units. I’d stay away from
All the bells and whistles add extra parts that could break. Do you know the square footage of the upstairs vs down stairs? 350 square foot per ton will get you close. But a manual J ( heat load calculation) really needs to be done.

 

[Jasons 69 Chevelle]

I’ve seen some other posts about HVAC and know there are some pros on this forum so I’m looking for some advice.

I’m finally breaking down and putting AC in the house. Been here 40 years and it hasn't been an issue until that last few years. Hotter weather and older age are not a good combo.

Our existing furnace (Carrier) Is pretty new so we’re going to keep it. Our house is 2 story, semi-open construction, 2400 sf, master bedroom downstairs, all other bedrooms upstairs. Currently we keep all the upstairs registers closed since no one is ever up there. Northern California location so basically zero humidity.

I can tell you that we are not AC people. We prefer open windows to AC so we will only run it when it’s over 95-100 for multiple days and the house doesn’t cool at night.

The reason I’m asking is we’re getting quotes all over the place. Not so much price all over the place but equipment. 3 ton, 4 ton, single stage, two stage, 14 SEER, 17 SEER, dual zone, left handed (just kidding on the left handed).

I understand the tons and really there isn’t much difference between 3.5 and 4 tons but what about the single vs 2 stage and the dual zoning (not an inexpensive adder)?

And one guy said it’s fine to put a lattice type fence 12” away. Another gut said a minimum of 24” all around. To an open lattice fence? Seems nuts.

They also all say “plastic pad”. Does this go right on the dirt or should a make a DG pad for the plastic pad?

Any other things I should consider before deciding?

Plus I've been quoted Carrier, Day and Night and Bryant, which I understand are all from the same company anyway. Is anyone better than the others or one to avoid?

Thanks

Also some Carrier brand units are getting LG compressors at random. Copeland is the compressor I prefer. Under the plastic pad you should put rocks like a French drain. Depending on your soil. I’ve see many units get washed out under the pad.

 

[shovelrick]

I agree about the washout Jason mentioned and it can happen with the hurricane pad too, the load calc will depend on your windows, doors, block or wood frame, type of siding, type of roof, attic type, crawl space etc. Y ou really should do this and in Fl. its required if the home never had central ac, you might want to think about one of these also, I have one in my system and you can actually tell its working by the fresh smell in the air, if you do ask about one let me know because I can send you one at cost, they're very easy to install if you're mechanically inclined and Im betting you are lol