Is it possible to fill too much refrigerant into an AC system? Is it possible for an HVAC technician to overfill an AC system with too much refrigerant (R-22)? For example, if the system needs 2 pounds, is it possible for the technician to force in say 3 or 4 pounds? If so, can this damage the AC system or cause it to malfunction and stop cooling? Yes , it can be done, but is usually the result of an under or untrained technician. Also low air flow will often cause somone to do this.Why do you ask??? Yes, you can overfill an A/C system. It will cause damage if it is excessively overcharged which it sounds like it may be. Depending on which brand it is it should trip off on high pressure. Hopefully saving the system from too much damage. Not sure why anyone would over charge a system by two pounds but I know it happens. Call someone else hopefully more knowledgeable to remove all the refrigerant and install the correct amount for the system. It kinda xxxx you got to pay for possibly two extra pounds of a refrigerant that is not getting any less expensive lately.

Thanks for the two answers. I asked the question because my AC system information sheet says it has a capacity of 6pounds of R-22. The system was not cooling well. Technician came and said that system needs refrigerant. He put in 6 pounds of R-22 @ $100/pound. System cooled wonderfully for two days and but now has is again not cooling well. The only difference I am seeing now is that with the AC running, there is a lot of ice formation at the point where one of the refrigerant lines meets the compressor unit that sits outside the house. I am wondering if anything is freezing in the lines preventing the refrigerant from circulating and transporting the heat away from the house. If the frost is at only one small location, ESPECIALLY a joint or coupling, I would guess that you have a leak there. Before filling the system, the technician should have done a pressure hold test to determine if the system was leaking, BEFORE dumping hundreds of $ of Freon into it. Dramatically low (or zero) pressure inthe system shouldl have tld him to check for a leak FIRST.

This leak may be what caused your system to drain down originally, or it may be the fitting he hooked onto to fill the system - can't tell from your description. What you are seeing now may be because he did not tighten a connection or fill port right after filling, and may not be related to the original problem at all. That is quite possible,, considering how fast it apparently drained off.AC systems do gradually bleed off the refrigerant pressure over the years due to diffusion through the pipes and threads, and through leakage past seals in the compressor, but a sudden loss of function (rather than gradual) means either a leak or a compressor unit problem.small air conditioning and heating unitThe technician should come back, do the job right (locate the leak), and refill the system for you FOR FREE, because he did not do it right the first time.ac unit cutting on and off

An overcharge in an air conditioning is definitely a problem. It causes high operating pressures and loss of cooling It also decreases life expectancy of the compressor and loss of indoor comfort. Check the difference in temperature on a warm day from the return air to the supply air. The difference should be 18-22 degrees in a properly ducted system with a clean air filter and normal air flow. 20 degrees is usually optimal. If the temperature difference is lower or higher you should have a compenent service company check the system.ac and heating supply store Does a freon leak mean I must get a new home AC unit? Can't I just get the leak fixed? A PSE&G technician was at my house to charge the freon in my AC. He told me that I've got a leak & that I'll have to get a whole new unit. This seems a little far-fetched to me, especially because my unit is only 10 years old. Can't the leak just be fixed?

The technicians are getting lazy, especially if the companies pay commission , then they would rather try to sell you a new system , than repair !Call and get someone else to perform a proper leak check on your system ,I've got systems that we service that are 40 years old and still operating. Call and get someone else to perform a proper leak check on your system ,I've got systems that we service that are 40 years old and still operating.The technicians are getting lazy, especially if the companies pay commission , then they would rather try to sell you a new system , than repair !good luck Source: Owner of hvac company 9 out of 10 times if you have a good tech with enough technical skills he should be able to find your leak. if it is a single leak he should be able to fix it. But now a days it is more advantage to sell you a new system than repair it because the fix is time consuming and they would rather have the tech stick to schedule than waste time looking for the leak.

time is money and techs are paid by the call then by the hourRaymond gonzalez Did he say where the leak is ? If in a fitting or line, simple and cheap to just repair or change that out. If in the exchanger coils, commonly they have to be replaced unless it is in a reachable spot that can be brazed. If in the compressor (compressor bypass leak) then that is a major component, and probably the most expensive part of the system to replace, so in that case you would be putting down a lot of money to fix a system that is out of warranty and is probably 65-85% of the way to its average service life of 12-15 years.One other possibility which he may have been thinking but did not say, is if it is an R22 refrigerant system, that is costing hundreds of $ to fill now that it is going out of production, and will cost more in the future, so he may have figured you were better off with a system that uses the replacement refrigerants. For more on that subject and when the phaseout takes full effect, see the discussions in Home - HVAC (link right below your question, above).

I would call him back and find out where the leak is (if he tested for that, rather than just checking the pressure and saying there was a leak somewhere), and why he recommended a new unit over repair.Then you can decide what you want to do, and if you wnt to get another opinion. You might want to check his firm's rating on Angie's List too, to see how much weight you want to give to his opinion. If the leak is in the "indoor" Evaporator coil, the cost to replace the coil, if not covered by a ten year parts warranty( you should check warranty), is far greater then 50% of a new system. These coils are not repairable , in most cases, there are numerous pin holes from Formicary Corrossion, and more on the way.The tech should and may have indentified the leak, if not ask that they do so.Most all new systems will have a 10 year parts warranty, though it must be registered with the manufacturer to be valid.Check out Carriers new Green Speed system, terriffic system, much lower utility bills.