Need help on tonnage question

Tonnage is 2.5 tons

SEER rating is 10

look on the mane plate on outside unit... has voltage ratings model serial type of freon factory charge etc.

Ask your installing company for the AHRI number. If installed with a
matching furnace and coil as listed in the certification then you will get 16 seer rating. If they installed something different than what is listed in the certificate then demand all parts listed or a refund.

This unit is a 3 ton unit
P3RA-10 SEER
3, 4 and 5 Ton Units
Cooling: 32,500 to 55,700 Btuh
P3RA- Cooling Btuh SEER
036K 32,500 10
048K 45,500 10
060K 55,700 10
Hope this answers all your questions
Please remember to Rate/vote for any solution that helps you out.
Leave a comment if you need more help.
Thanks for using Fixya.

Look for your model number on your condensor, outdoor unit. Your tonnage will be towards the end of it and divisable by 6. I.E. 36=3tons or 42=3.5tons. Ac units are messured by the half ton. If you have a split system I.E. heater inside and ac outside your system will be 1 - 5 tons. If this doesn't help post your model and serial number. I can then give you tonnage, age, so forth.

This is a 3 and 1/2 ton unit.
The 042 in the model number is the tonnage of your carrier unit.
AC tonnage is based on 12,000 btu per ton.
12,000.....1 ton
18,000.....1 and 1/2 ton
24,000.....2 ton
30,000.....2 and 1/2 ton
36,000.....3 ton
42,000.....3 and 1/2 ton
48,000.....4 ton
60,000.....5 ton.
There is no 4 and 1/2 ton unit.

First off - the 'rule of thumb' is 600' per ton of Air Conditioning. In other words your old unit is a 2 ton unit. So - 2 tons x 600' = 1200'. As you can see if you install the 2.5 ton unit - you will be installing a AC that 'could' cool a 1500 sq ft house (2.5 x 600' =1500 sq ft.). Slightly more than what you need; and the 3.5 ton unit is 'way to big,' (3.5 x 600' = 2100 sq ft.).

Note: fyi - many in the AC business will sometimes refer to tonnage in btu's, i.e. 1 ton = 12000 btu - hence a '2 ton unit' can also be referred to as a 24000 btu unit and vice versa.

So... from the above - you can easily see that "2 tons" of Air conditioning is what is required to cool the 'average' home of 1100 sq ft. "roughly speaking."

Note: it is always best to have a professional 'size' your cooling/heating needs.

One of your questions was could you 'mix tonnage?'

The answer is 'usually you don't mix the tonnage of your outside/inside units.' However, professionals sometimes do (mix the tonnage) in certain situations, and installing a 2.5 ton outside unit with an existing 2 ton inside unit is often done, however, there are some 'tech issues' here and - I would "again" recommend that you call a Service Tech to help you with the sizing/mixing of your cooling/heating needs.

hope this has helped

Your problem is that your 13 seer outdoor unit is not compatible with your 10 seer indoor unit, even though the tonnage is the same. The metering device on 13 seer indoor units is different. Most 10 seer indoor units do not have an expansion valve. When you change from a 10 seer outdoor unit to a 13 seer outdoor unit, you must, at the very least, change the from a fixed-orfice metering device to an expansion valve.

without the serial # can not give year but is likely a 10 seer unit and a 3 ton

3 1/2 ton unit the 042 tells me.