Need advice on replacing our HVAC system
I live near Philadelphia and our 2 story home is ~2400 sq ft and I am considering replacing our HVAC system within the next week or so because our AC is no longer cooling the house (so we have been without AC for the past 2 days), so any advice would be appreciated. I am just starting the research so I may not be familiar with all the terms or have all the necessary information. I am hoping you will help me to know what questions to ask.
Our current system is a Carrier and it's 19 years old. We had to repair our AC last summer and again earlier this summer but it has failed us again. So maybe it is time to replace it.
I have had a few contractors come out but their differing advice is confusing me. Our current system is 80% efficiency furnace with a 10 SEER AC.
Some contractors are recommending a 2 stage system while others are saying a single stage is sufficient. Some say it is not worth getting a higher SEER than 13 because it'll take too long to recoup the cost in energy savings as compared to 16 SEER, for example. One person suggested a 4 ton capacity (current system is 3.5 ton) while another said stay with the 3.5 ton and get a stronger blower.
Can you help this newbie? Thanks!