She lives in a small, simple house in southern Mississippi. It's only 1700 square feet. Why then, she wondered, were her summer electricity bills running more than $600? She didn't have anything that could be a big energy hog, like a swimming pool, and she didn't do stupid things like leave all the doors and windows open while she ran the air conditioner. What could it be? She called her electric company, one of the co-ops in Mississippi, and they sent someone out to investigate. Utility companies get calls like this all the time, and they've learned from experience what most of the main causes of high bills are. When the utility investigator arrived arrived at the house, he asked her to tell him anything she knew that might help him. "Well," she said, "the air conditioner runs all the time, but the house won't even cool down to 80 degrees." "Ah, that helps to narrow it down a bit." He went to work, and it didn't take him long to find the problem. He measured the temperature drop across the air conditioner coil and found that the air on the 'cool' side wasn't much lower than the air on the warm side.

And both were much warmer than they should be. OK, that could be a disconnected duct in the attic, he thought, like the one from a different house that you see above. A look in the attic, however, showed that wasn't the case here. Besides, a disconnected duct would increase the bill, but it almost certainly wouldn't quadruple it. His next step was to turn off the breaker to the electric resistance heat (a.k.a. strip heat) in the HVAC system. This is basically a giant toaster inside the air handler. Heat pumps use it for supplemental heat. In some homes, it's used as the primary heat source. It's not cheap, though, especially considering that the same electricity going into a heat pump will yield two or three times more heat. Anyway, the utility investigator turned off the breaker to the strip heat and watched what happened to the meter. In the summer time, turning off the strip heat should have no effect at all on how fast the meter spins because it shouldn't be running.

Strip heat is for cold weather. In this case, the meter went from spinning fast enough to saw wood to moving as slow as a horned passalus (photo at right) going for a walk in the woods. "Well, we found your problem, ma'am," he told her. amana window air conditioner heat pump"Your heating and cooling system was doing both at the same time, making you spend a lot of money to stay uncomfortable."danby designer ac unit This problem often results from a thermostat wired incorrectly so that the system kicks on the strip heat when it shouldn't. hvac unit dripping waterSince anyone can go down to the home improvement store or the Interwebs and buy a thermostat, a good number of these problems result from DIY jobs. It seems crazy to think that someone wouldn't notice that the heat is running in their home in summer, but they don't feel heat coming out of the vents.

That heat gets mixed with the cool air from the air conditioner. They cancel each other out, both using even more energy because they're fighting each other. Got high electricity bills in summer that you don't understand? Check your strip heat. When Is 100% Efficient Not Good Enough? Sex Advice, Diet Tips, Decorating Ideas, & HVAC Design I have an old a/c unit that uses R22 , can I replace it with a unit that uses the new refrigerant or do I have to change other components? I have an old a/c unit that used to use R22 refrigerant and I need to replace the condenser unit. Do I have to change it to the same R22 or can I change it to the models using the new refrigerant without having to change other components on the central A/C unit such as the inside blowers, etc? Do you have the same question?  There are R22 units available, but be advised the the cost of R22 has tripled this year. Best advice is to go with a complete new system using Puron/ R410a.Puron has been around since the late 1990's.

Proven product from Carrier. Answered 4 years ago Just replace the part that you need, with a replacement the vehicle specifies,and purchase a conversion kit for your freon, its now called R134A ,this new product is made to be used with just about any system out there, you will not need any additional parts or any special parts either, but you need to get your system flushed after you install new parts, remember a conversion kit with R134A. R134 conversion is for automotive air conditioning,not your home AC system. Replacing the condensing unit(outdoor coil) with R-410a, will require a new evaporator coil(indoor coil) and a line set(copper tubing connecting units together) flush or new line set(better choice). Sorry, i wasn't paying attention to the question, i was going by what someone waas telling me , so the information i stated does not apply at all. If you change to the new refrigerant you will have to change the coil, line, etc. Not a cheap proposition, and if your coil space is limited (i.e., as in many California homes) your choice of systems may be limited.

Some states forbid manufacturers from shipping units with R22 in order to push "green" technology. However, some manufacturers will ship empty units (no refrigerant); you can then have your A/C tech reclaim the R22 from your old system. This is by far the cheapest option, perhaps sub-$2,000. There are a few options for residential and commercial ac systems :1) Change equipment to a R-410a system I.e. ( air handler and condenser , furnace , coil and condenser ) and flush or replace copper lines , the oil from R-22 systems doesn't mix with the oil used for R-410a .2) Replace just the condenser only with a R-22 compatible , dry shipped unit , which means it doesn't have the refrigerant in it and use the two drop in refrigerants I have mentioned 3) There are a couple of drop in replacement refrigerants for residential and commercial ac systems MO-99 and NU-22 the use of these refrigerants are 50% cheaper than R-22 and work just fine .4) Use R-22 and pay a higher price .Good luck on your decisions !

Answered 3 years ago 1) As you can see from the other answers, there is no simple answer - a few units out there can simply have pressure regulators changed, be flushed out, have your new condenser unit installed, and be charged with the new gases. Others require new evaporators and/or tubing because of the higher pressure needed for R410A, and in many cases the compressor has to be replaced too - so pretty near the whoope system except for any ducting may haveto be replaced, depending on your make and model. R410A is actually a mixture of two other refrigerant gases - R32 and R125, and some units have been found to corrode in contact with one or the other of these gases. 2) There are also alternative gases - R44 and R424A that can be used instead of R22 and, in SOME units, can be run without modification other than flushing the system before putting in the new gas. 3) Therefore, you are trapped by two factors - first that R22 is being phased out and getting more expensive every year, and while it will be available as long as your current unit is likely to live, if you have a leak in the future it may end up costing $1000 or more to refill it.

Secondly, since the condenser unit which has to be replaced is pretty pricey already, you need to weigh the condenser replacement and possible future costs (including compressor life) against the cost of installing a new unit now. Obviously, whether your current indoor evaporator/fan units can handle R410A or would need replacing would be a significant consideration in your decision. 4) If your unit is less than about 10 years old, you have a tough decision, and you need to factor in your financial situation and how long you plan on living in this house - certainly a minimal-cost repair now makes more sense if you move every few years, whereas ifthis is your forever home and you job situatiuon is not likely to force a move, then a new unit might be less hassle and make more economic sense. Ifmore than 10 years old, then I would personally say look at a total replacement now, especially if your unit bled off the Freon so you are goingto be paying for gas replacement cost of probably $500 or so as well during a condenser replacement.

Answered 2 years ago If you desided to go with the new freon you need to change it all . This is fact ;for a lot of resons. So with that said . If for some reson you try mixing up the system be perpared for major issues it would be like airing up a tire past 32psi too 100psi and hit the hot high way at high speed. But the tire would last longer.Now im in the repair bussiness so replacing isnt always the best anwer. A honest OPPIONION would be the best' theres normaly nothing that cant be fixed. but when its old an rustic and wore out my be it isnt cost effective Answered 1 year ago 134A is used in Refrigeration Units and Indeed could be used in an old R22 system if you replaced the compressor and do a few modifications like install a receiver, which may or may-not be needed depending on condenser volume...Now as for the fellow suggesting 290a or the 22a, the EPA sent me a letter, a few years back, stating WE {HVAC} techs cannot use it in HOME HVAC units because it is a Flammable [Propane} However I have used it in MY own system to experiment and it indeed works close to R22 without any oil change or modifications.

We can however use it in chillers and units that have no flame around them.. or so the letter stated...in your central air and heat, your evaporator unit is directly attached to the heat source which could potentially cause an explosion if the system leaked in the air exchange area. So that isn’t really an option for most home owners… 410a is the supposed standard of replacement but you have to change pretty much the whole system because of the higher pressures… Also Make Note that every time you buy something you have to pay TAX on it, makes the government want you to buy new everyday if they had their way. As for those who say 134a is only for your car…I say phooey…if it is used in major walk-in Refrigerators and Freezers up to 7 tons…it surely can be used to cool your house. You just have to find a Tech Smart enough to modify your old R22 system. And you can get a 30lb can of 134a at Sam’s Club for around 90 bucks, about the same as 410a …Now R22 has skyrocketed as of 6-2015 to over 370 bucks a 30lb can "Tech Cost" …retail has to be 600 or better.