Advice on replacement HVAC

[Jpohara]

I'm looking for advice on HVAC systems. I'm getting ready to replace my system and I've had 4 companies out over the last 2 days and I want to make a knowledgeable decision.

I know picking a reputable company is #1 in making sure the system works properly but 3 of them have great reviews with 5 of 5 stars. So now it comes down to the details. I live in Phoenix, AZ and it gets really hot in the summer. I own a manufactured home so insulation is not the best and it's an older home. The winters are mild and I don't really use the heater and this past winter I didn't even turn it on.

The home is a double wide and is 1,250 sqft. It currently has a nordyne compressor and nordyne furnace. The ac is 3.5 ton. I was told 1 ton is for 400 sqft so 3 ton is for 1,200 sqft. Considering the home is 50 sqft larger than that and it has poor insulation I'm assuming that's why they oversized. I asked about going large to a 4 ton but I was told by one tech that it was possible but another said they wouldn't suggest it because the ducts are not made to handle that airflow and the returns aren't made for that either. He is worried about the unit short cycling. I've decided I am fine replacing the 3.5 ton with a 3.5 ton and ruling out the 4 ton. The current nordyne ac is manufactured 10/05 so almost 15 years old and the furnace is 06/06 so almost 14 years old.

My current reason for replacing the unit is because the furnace wasn't working properly because the a coil was freezing over and if I left it on long enough the lines outside would freeze. I had a company come out last summer and they told me the piston was clogged or stuck and they would have to evacuate the lines, clean the lines, and recharge the system. The quote was really high and was about $1,500 so I asked about getting a replacement. They took measurements and said they would get back to me within 2 days and a week went by without hearing from them. I contacted them and no word from the manufacturer was their reason. After 1 month I decide not to go with them and summer was over so it wasn't a concern anymore. I did contact 2 guys though and they both said it looked like it was low and refrigerant and it's really unlikely that the piston is stuck. One guy said the rusty a coil probably has a leak and I can recharge it but it will eventually leak out. I could replace the a coil but it's not cost effective because it's r22 and would be almost half the cost of a replacement system.

I've started getting quotes for a new unit and I'm trying to decide what type of setup is best. I was told nordyne is made for manufactured homes and is the standard and meets code requirements or something like that. He said it can handle the high static. I looked up brands and found trane to be a top of the line and 1 guy only works with trane and said they don't make a high static furnace for manufactured homes so it would be a trane compressor and a Coleman furnace. Is it ok to have that setup? I was told not to mismatch and I've read that it might work initially but will reduce the efficiency or lifespan as time goes on. What I read though seemed to be talking about replacing an ac or furnace without replacing the other. What if they're both replaced at the same time? Is it ok to mismatch units? My other option is Goodman compressor and Goodman furnace. My final option is nordyne which apparently is called air temp and would be a matching system. What's the best option or are they all good options? All compressors offer 10yr warranties and 5yr on the furnace coil but Goodman only offers 1yr on the furnace and Coleman offers 2yr on the furnace. Plus it's 2yr warranty on labor and workmanship with any setup. So ultimately it comes down to whether or not I should get a matching system or can I mismatch like with a trane and Coleman? The Coleman offers 1 extra year warranty on the furnace compared to the Goodman which is nice and it's technically $100 cheaper with one company because apparently it's more expensive to get the Goodman furnace which I guess is really made by vortex. I will find out today what the warranties are on the nordyne/ air temp but that guy also quoted me the highest price.

What brand would you suggest for a manufactured home? Can I mismatch systems like having the trane compressor with Coleman furnace? Or even Goodman compressor with vortex furnace? Or should I go with a matching nordyne/ air temp setup?

[pecmsg]

http://efficientcomfort.net/assets/d...ign_Issues.pdf

Not an indorsement in any way but required reading:
https://www.angieslist.com/articles/...vac-brands.htm

[Bazooka Joe]

Did they check the inlet side of the indoor coil, as a dirty coil will also cause your coil to ice. The trouble you may get with mismatching as an example a Trane outdoor unit and a Coleman indoor coil and furnace your manufacturers warranty may be cut in half. Tranes web-site says in order to get the full manufacturers warranty systems need to be a AHRI match to receive the maximum manufacturers warranty, using Trane equipment and replacing everything at the same time.

Possible there is a Trane AHRI match with a Trane indoor coil to Trane outdoor unit with a ( as an example a Coleman furnace ) to get the full manufacturers warranty, but I’m not aware Trane makes a system for modular/mobile homes?

Not saying it’s not true, ( piston stuck ) but piston metering devices are very simple and trouble free for the most part. They just slide a tiny amount. They slide when using with a heat pump as the refrigerant pressures are reversed. Doubt your piston has ever moved in 16 years and became stuck as you have a straight A/C application. Even during off cycle, when thermostat satisfied as the high refrigerant pressure is still pushing it until the low side pressures match the high side and equalize. But hey could be wrong there...

IMO I would 1st do a load calculation then pick a matching system of your choice that is made for manufacturers homes. Register the system afterwards.

Air Temp is owned by HVAC distributor RE Michel but is a rebadged Nortek/Nordyne.