Replacing Air Conditioner questions

[10scoachrick]

Originally Posted by turf3

Best way to avoid thermostat problems is to buy the traditional round type.

If you are cold, walk over and turn it up. If you are hot, walk over and turn it down.

I currently live in a house with three of these, two of which I believe are original to the house (1953).

Computerizing thermostats is another case of something that, although you can do it, you probably shouldn't.

I'm not sure it's necessary to access the 'stat from parts unknown(work, play, Europe); but a programmable 'stat is very beneficial to those with certain schedules. I'm not crazy about our Nest; but DW wanted it, so I installed it

[DashRiprock]

I'm not aware of any particular reason you need to replace both units at the same time.

Mentioned above, but I highly recommend you go 1/2 ton over whatever their load test comes up with. I don't trust engineers in Syracuse to understand Texas heat.

I'm not familiar with the Nest specifically but there is no reason not to have a programmable thermostat. They're pretty cheap at Home Depot and easy to install yourself, but don't most new units come with them now anyway?

[teasipmom]

Originally Posted by austin-steve

I deal with dozens of HVAC service calls each year for rental homes I own or manage. I regularly have to make the call on "fix or replace".

It comes down to some basic questions:

1) Is the system operating as designed and cooling to specs? (14-20 degree splits)
If not, is the reason curable by servicing/cleaning the system, and can another 2+ years of life be reasonably expected for a $200-$500 tuneup? If so, we repair and keep.

2) Is there a freon/coolant leak? If so, and it's not something easy (like a valve) and/or not something Stopleak + recharge will cure, it triggers entire system replacement because the older coolant R22 doesn't match up with the newer 410a, and is extremely expensive now. All new systems/equipment now ship with 410a, which operates at a much higher pressure, so the condenser and evap won't match up when you try to mix systems. There are workarounds to make them work together, but on my properties, I just go for an entire new Bryant system with a 10 year warranty if either the condenser or evaporator coil has to be replaced. then it no longer makes sense to salvage the furnace, so just get an entire system.

I would get at least 3 opinions, and at least two from a small mom and pop HVAC person (versus the big turnkey brand people).

Additionally, in your case, if both 16 year old systems are same-brand with original components (condenser, evap coil and furnace), and one is a goner but the other serviceable per #1 above, I'd swap out one but keep the other for now unless you have the cash on hand and can get a substantial discount for doing both at once.

I still have a few 30+ year old systems running in rental properties, and many 20+ year old systems. But we've also had to completely replace a lot of 8-12 year old systems. There doesn't seem to be rhyme or reason, some just develop coolant leaks for no apparent reason, while other seems to be like the energizer bunny and last forever, even in a rental property.

Steve

I'm going to save your checklist and print it out. Thank you Austin-Steve!

[teasipmom]

Originally Posted by DashRiprock

I'm not aware of any particular reason you need to replace both units at the same time.

Mentioned above, but I highly recommend you go 1/2 ton over whatever their load test comes up with. I don't trust engineers in Syracuse to understand Texas heat.

I'm not familiar with the Nest specifically but there is no reason not to have a programmable thermostat. They're pretty cheap at Home Depot and easy to install yourself, but don't most new units come with them now anyway?

yes, it seems they have all jumped on the band wagon with the programmable thermostats. I think one thing specific about Nest is that it is a 'learning' thermo, in that it can adjust itself to either the indoor/outdoo temp and user preference. I don't know if the ones that come with the units (i.e., Trane, etc.) do that right now, but I'm sure they are on their way to do the same thing.