ReplySounds real good, should be keeping the humidity down with thelong run times, that will only make it feel that much more comfortable. It sounds like you have a properly sized system aand these are rare Enjoy.
Regular Guest
I live a fairly newer house in the Chicago suburbs and the A/C seems to be running an awful lot to maintain the temperature in the house. Right now it is 94 degrees outside with a dew point of 56 degrees and the air conditioner has been running pretty much non-stop for the past hour. I have the thermostat set at 75 degrees and the house is comfortable, but I was just concerned at how much the unit was having to run. The unit is supposed to be a 3.5 ton carrier. I measure the temperature on the air coming out of the registers at it is 58 degrees. The house is a 2800 sq foot ranch style house. The living room, family, eating area and kitchen all have 11 to 15 foot high ceilings. The front of the house faces south and has about 45 sq feet of windows covered with both blinds and drapes that are currently closed. Does it seem normal for the unit to run like this given the conditions or should I have the unit checked to make sure it is working correctly?
Professional Member
Sounds real good, should be keeping the humidity down with thelong run times, that will only make it feel that much more comfortable. It sounds like you have a properly sized system aand these are rare Enjoy.
Regular Guest
3.5 tons for 2800 sqft is undersized. do you have 2 units or 1.
Global Moderator
Gee, around here we have 3 to 3.5 ton units on 2800 sq ft all the time. They aren't undersized by Manual J standards, maybe by the ton per sq ft standard.
75 and comfy in the kind of heat we're having sounds like a properly sized unit doing its job.
Professional Member
maybe for caliOriginally posted by moe-air
3.5 tons for 2800 sqft is undersized.
Professional Member*
Question: should I have a/c checked?
Answers:
NO, if you have an unlimited source of disposable income to apply to repair, replacement, or utility costs
NO, if you just like living on the edge.
NO, if you are into 3:00 a.m. 'surprises.'
NO, if your last name is Lennox, Carrier, Bryant, York or Trane.
NO, if being cool during the summer months is not a priority for you.
NO, if not freezing in the winter is not a concern.
YES, if you want to have the most efficiently operating system possible.
YES, if you want the system to last as long as is reasonably possible.
YES, if you don't get warm and fuzzy everytime you write a check to the local utility provider
YES, if you like avoiding the 'unknown and unexpected.'
YES, since most of us (even in the business) aren't direct decendents of the aforementioned corporate movers and shakers and have to pay for product or services.
YES, since if you're like most of us you want to be comfortable in your home, year round.
Moral: have a professional survey the system and make the necessary notations and/or recommendations for the maximum use and efficiency of your present and future systems. If that person is honest and straightforward with you and deals with you with a high level of respect and integrity, then reward that individual with the opportunity to make the necessary recommendations. If these meet with your approval, then allow the same individual to follow through.
Everyone has a purpose in life..........even if it's to be a bad example.
Seek first to understand, before seeking to be understood.
Regular Guest
It's been in the mid 90's here a lot lately. My A/C runs from about 3pm until 11 or 12 at night non stop. In other words, perfectly!
Does this site have a FAQ or sticky? Seems like you guys get a lot of questions on "It's 99 degrees out and my A/C can only manage 78 degrees" and "my A/C runs all day when it is really hot out". It could help people get the answers they need quickly, and less likely to blame you people for the perceived problem. I will admit I haven't snooped around much and this site might already have that. I know it has a search button, I've used it.
Professional Member
Doesn't sound like anythings wrong. 94 outside puts a load on that house.....expect it to run longer. Just be thankful you only require a 3.5 ton in that 2800 sq ft....sounds well insulated.
If everything was always done "by the book"....the book would never change.
Banned
I'm with John L ,on this one ,have it serviced once a year,slower times of the year are the best time to call.
Regular Guest
to operator.
in cali, typical 2800 sqft tract home has 4 or more tons. my home is 2917 with a 5 ton bryant. previous home was 1711 with a 4 ton trane. newer homes have 2 units for each floor. co worker has 3066 sqft with a 3.5 and 3 ton unit.
Regular Guest
The problem is your unit is very much undersized.
My home here in Louisiana is only 1600 sq. ft and have a 3 ton.
I would have installed you a 5 ton if I had did the install or at least try to convince you that your home required a 5 ton and let you make the call.
Regular Guest
I was actually willing to pop for a 4 ton, but the builder insisted that the 3.5 was what the HVAC guy was recommending for our house. He said that the four ton wouldn't run enough to take the humditiy out of the house. This is our third summer living in the house, but I never noticed the A/C having to work so hard before. Then again last summer was a record cool summer and this summer has been the exact opposite. The average high temperature for Chicago in June is 82 degrees.
Global Moderator
In our suburb, we have a common floorplan 3 bedroom 1800 sq ft ranch. We've installed 2, 2.5 and 3 tons of cooling on this exact same house. So which is right? Can you guys in Louisiana or California tell me? You told him his was wrong without seeing the house or knowing much about it.
The answer is all of them are right. Anybody going by sq ft doesn't know what they are doing. The 2 ton homes are well shaded. The 2.5 ton homes aren't shaded but face north-south with no east-west windows. The 3 ton homes are east-west facing with no shade. Hmmm, all the same house, same sq ft with radically different cooling needs. Guess that's why the Manual J was invented.
Do your California and Louisiana homes have the same insulation as his? Gee, you can't answer that - you don't know what he has yet you know his A/C is undersized. Well, my guess is he has R38 ceiling and R19 walls. That what they do in your area?
Ricardo, if you are staying comfy in the extreme heat we've been having in the upper Midwest, your system is NOT undersized. hilton's 5 ton would have you running dehumdifiers all over the place in the normal humid 82 we typically have because it would be short cycling something fierce.
Banned
Originally posted by BaldLoonie
In our suburb, we have a common floorplan 3 bedroom 1800 sq ft ranch. We've installed 2, 2.5 and 3 tons of cooling on this exact same house. So which is right? Can you guys in Louisiana or California tell me? You told him his was wrong without seeing the house or knowing much about it.
The answer is all of them are right. Anybody going by sq ft doesn't know what they are doing. The 2 ton homes are well shaded. The 2.5 ton homes aren't shaded but face north-south with no east-west windows. The 3 ton homes are east-west facing with no shade. Hmmm, all the same house, same sq ft with radically different cooling needs. Guess that's why the Manual J was invented.
Do your California and Louisiana homes have the same insulation as his? Gee, you can't answer that - you don't know what he has yet you know his A/C is undersized. Well, my guess is he has R38 ceiling and R19 walls. That what they do in your area?
Ricardo, if you are staying comfy in the extreme heat we've been having in the upper Midwest, your system is NOT undersized. hilton's 5 ton would have you running dehumdifiers all over the place in the normal humid 82 we typically have because it would be short cycling something fierce.
All very true!
Regular Guest
Insulation is R15 in the walls. Most of the ceilings are R-38 except in the cathedral ceiling areas where they used R-30 batts. The house is fairly air tight. The contractor did a pretty good job sealing it up. Anything that he missed I've taken care of over the past two years. It definitely felt very refreshing coming in the house after doing three hours of yard work in the ninety-five degree heat.
Professional Member
Baldloonie is correct. hey bald staying busy in indy i bet im just down the road in terre haute
Professional Member
thanks for pointing that out Baldloonie,
I can bet hilton and moe have heating systems waaaayyyyy undersized
Regular Guest
bald loonie. not an installer or engineer.i'm in service. thousands of homes like this in cali. are you saying these home installers don't use manual j or using cheap insulation material.no difference if house on north or west shaded or not.i have also worked in resi additions never used manual j. boss used sqft and some duct calculations. this is also in a class given by ihaci in san diego. bottom line houses, customers have been fine.
Professional Member
I think loonie is trying to point out there are many variables to consider when sizing
you are in cali, much different enviroment than chicago, you cant say the system is undersized, it may be for your area but not this way.
with the example he shows that a rule of thumb could have led to some very unhappy people or worse situations.
I have found that out this way, no one, does a man j.
sister needs one for an addition and cant find a company that can do one.
I dont install so have'nt had the need.
Professional Member
let me see if i understand this. we size the equipment by the sq ft and thats it ? that sounds easy enough. And all this time i have been wasting my time accounting for r-values ,window sq footage, etc,etc,etc. I remember some years back i installed central air system i home that was poorly insulated then a few monthes later the customer calls and said that mold was growing on baseboard.when i went to customers home she told me that she had the house re insulated, well now the system is to big this is why i dont go sq footage alone.
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