my 3 ton outside AC unit went out...can I replace it with a 4 ton AC unit...a friend has a free one?

Question

my house is 1850 square ft....I don't know what size AC unit I have on the inside.

Answer 1

Have done heating and cooling fo 35 years--IT WILL NOT WORK!!! If your system is over 10 years old [most likely a 10 SEER or less--a new 3 ton ac unit will not function with your old "A" coil!! The cost of cooling will be high! and the cooling effect terrible! The new systems are way more efficence-- 13 SEER and up. It takes 4-6 times as much electricy to start an air conditioner as to keep it running--so oversizing is not a bargin!! A 4 ton on a 3 ton system would be a nightmare!!

Answer 2

You can actually have an "orifice" or "TXV" replaced on the 4 ton unit and make it act like a 3 ton unit. It won't be the best thing to do but you can make it work.

The best thing you can do is to get an A/C professional look at the unit and give you an advise. Keep in mind, you have to ask someone to do this for you, as you cannot do it by yourself both knowledge wise, and regulation wise. (and safety) Don't forget to factor his fee into the equation also.

Answer 3

4 tons may be a bit of overkill, but if it is free, then why not. The only trouble with too big a unit, is that it doesn't stay on as long and it will circulate the air less. So you will get less humidity pulled out of the air.

You will have to replace the inside coil also, with a 4 ton one. I hope that it fits your furnace. good luck.