Try to f> If a house currently has multiple window air-conditioners, are these
Maybe, but they cost a lot less, with no ducts or concrete pads or plumbing or special electrical wiring, and low-cost Chinese and Korean labor, vs local HVAC criminals. At $69 for 5340 Btu/h at 10.2 EER (Daewoo), a 3-ton system is $69x36K/5340 = $465.17. And if one breaks, the rest keep working.
So you might close the doors and only AC those rooms, effectively doubling the SEER of the window units, compared to central air. An X10 system with occupancy sensors might do this automatically.
i used to run 3 6000btu window units and at the time the electric bill was 125.00 in july. i put in cenral air and the electric bill was 75.00 in august . running the new larger scroll compressor was cheeper than the 3 compressors in window units, better cooling,and less hassel.lucas
hey , there was a company that started using rotory compressors in central units back about 20+ years ago and their name was Fedders corp.. They started putting the rotory compressors in their central units and due to the 100% failure rate, they went belly up or bankrupt in 3 years after starting to put them in the central units.
The problem was this as to the 100% failure rates . The Mass of the shell of the compressors over 2 1/2 tons was too big to let all the heat out and not heat up too much and burn it's self up. By Now a days they must have design it right to do it by now.
In 1960 GE made its first rotary (roller/vane type, I dont think it was a rotary vane, but a roller thats why it is so dependable, the vane moves in and out..thats it, it does not scrape on on a rotating surface) compressor for split system AC units in the under 2 ton range. Bullet proof. My RV has one of those in its rooftop AC from the look of it.
the Daikin brand (japanese) split system heat pumps used a roller type as well. Those went up to 5 tons ( and 4 or 5 indoor coils )
I think scroll compressors have problems in the smaller sizes because of manufacturing tolerance issues...in larger compressors the same tolerance limitations create less of a loss of efficiency (pressure leaks past the scroll)... I havent paid any attention to how small a scroll compressor is made but it seems like 3 tons?
ASHRAE suggests one use 5- 10% for duct loss. and mentions that due to *air leakage*. It is interesting that you dont see thermal conductance loss through the air ducts thin insulation mentioned more often...or for that matter through a packaged units ultra thin evap coil/ blower cabinet insulation. I think the ASHRAE 5 to 10% factor must include that.
You can put locks on the windows so they can't raise them. With locks, it wouldn't be easy to get one out without making a lot of racket.
I bought a Whirlpool Quiet Partner Series; it is very quite. It is in the window of the living room where I watch TV; the one I had there was noisy and interfered with TV enjoyment!
My two are each 6000-Btu/hr or less; easy to install; some leave the bigger units in the window the year round.
I agree with you on the money point. I also love to see and feel the performance of a central system that is really delivering to its rated Btu/hr specs.
I see the ones here speaking has stars in their eyes of what they think the Oakdale, La. 71463 HVAC service company makes money wise. There is 2 of the 5 service and installer companys in town that thinks changing out a 5 ton condenser for a job at cost + $125.00 = the job done. $885.00 sales tax included for a Evcon / Luxaire / York. I bid $1,500.00 in Rheem and $1,275.00 in Goodman. The other bidder told the preacher that i was a ripping the church off by wanting these high prices. The sad part here is the preacher believed him but the other fellow would not come back to fix the job with a freezing up expanion valve problem. They called me to come fix the mess up and i told the Preacher it would be $200.00 to fix it. he said that seemed way to high to fix it. i said then you know it could run $300.00 or so the more I think about it. I went a head and did it for $225.00 but i will never get use to Idiots in the customer base.
3 of the 5 service companys have other jobs and suppliment their income with hvac work. There is only 2 companys that do this full time for a living, Myself and one other. If you want to work residentiual jobs. You have to put up with a fellows who thinks Cost + $125.00 for condenser units and Cost + $250.00 for complete system change outs [ furnace , coil, and condenser ].
I thought about moving years ago but did not for some reason.
The way I figure it, rotary means that the armature and assembly goes around, rather than recip back and forth. Scroll is one of the types of rotating compressors.
Though, most guys in the trade would see it your way.
In your situation, I would improve the insulation situation and do everything possible to the windows and doors to reduce the heatgain. Also, do everything possible to reduce air infiltration.
Then I would go with the newer smaller 6000-Btu/hr quiet window units; like the Whirpool Quiet Partner Series with electronic cordless controls. Using a "Wind Machine 3300 | 20" fan," my little 6000 room A/C cools
920-sq. ft., three open rooms and part of the hall in 100-degree high humidity 112 to 116-heat index weather, --to 78-F or under and 55 or less percent relative humidity; very comfortable. Read my linked page on how that works:
formatting link
My July electric bill was $45.10; I have an electric hot water heater, electric range, a refrigerator, two TVs and a PC. I never use my old clothes dryer.
My upstairs unit is a Kenmore Cool 'N' Lite 5,950-btuh window A/C, by using another 20" floor fan on low speed, it cools one bedroom, the hallway, stairwell, and the bathroom.
I have central oil heat in a two-story home with a deep basement that was built in May of 1937, 68 years ago. The duct system was installed for a gravity airflow wood fired furnace. - udarrell - Darrell
Turtle, I think you should have moved. You need to get paid for you hard work and years of experience.
In hot (& humid) climates with long cooling seasons I wish every county government, utilizing the power companies, would fund an Energy Audit campaign to reduce the massive waste of energy in America. (That ought to get some feathers ruffled.) - udarrell - Darrell
the Heat was generated in the shell of the compressor by the rotor and not as it was leaving the compressor like Scroll or piston. No Stormy Poor Design.
No Stormy , you don't have a 100% failure rate caused by too hot of weather or not cleaning the condenser. Most of the failures were the first time the system had a run 12 hours straight without turning it off to cool off. i changed one out under warranty for a chicken place here and in about a month later the rotory compressor went out again. Fedders told use to have it fixed and send the bill to a law firm in New York and see if they would get paid. The customer just bought a new condenser and forgot about it for Fedders being in bankruptsy court and all.
No i did not sell it to him for he work for a chicken fast food chain call Fatsos Fried Chicken and had a deal cut to buy wholesale of all the hvac equipment and get their installer to put it.
The ideal of getting the hvac system to working right by a engery program would be a good ideal for here laterly about 1 in 5 calls of hvac trouble is too much freon in the system. They gas them up in cool weather and when it gets hot. They will stop working for too much freon in them.
Sticking to the question and ignoring my personal opinions: This would take an electrical engineer doing calculations to get an accurate answer. There are many variables, the most important of which is the size of the house in question. The answer would be different for an 1800 sq ft ranch than it would be for a 4000 sq ft, 2 story house. A typical central air compressor runs on a 30 amp circuit, a typical window unit on a 15 amp. The majority of the electricity used occurs when either unit kicks on. So in either case if the units run longer and start up less often the efficiencies rise. Poorly sized central units "short cycle" and that condition greatly decreases the cost efficiency. Same is true of the window units. A larger house would require two or more compressors. In addition, central air systems require an air handler. Once again, the answer will be different if the house already has hot air heat and the A/C coil is just going to be added to it rather than a new, separate air handle installed just for the A/C. Air handlers typically run on a 15 amp circuit. Once again, one or two depending on the size of the house. So every time the central unit kicks on you've got juice running the compressors and the air handlers with the total draw being a complex calculation of the total wattage required, the initial startup surge, and the steady run-time usage. The window units do the same, but the combined wattage would need to meet or exceed the central unit to use the same amount of juice. You buy central air for convenience, comfort, and prestige. Forget about the payback. That comes when it's time to sell the house.
"Nehmo" wrote in message news:aIQIe.722$ snipped-for-privacy@tornado.rdc-kc.rr.com...
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.