Rheem Modulating or Carrier 3 stage
I live in the San Francisco Bay Area so the climate is relatively mild. Mostly winter temperatures are in the mid 30s to mid 40s at night and high 40s to low 60s during the day.
I am choosing between a Carrier Infinity ICS model 58MVC080F-1-14 (3 stage) and a Rheem Prestige modulating furnace model RGGD07NMCKS. I will be running the fan to filter the air 24 hours per day. The Carrier will have a Lenox HC-16 media filter and the Rheem a Honeywell Model F300E1035 – 200 CFM electronic filter. The cost is about the same and assuming there is no difference between the contractors, is there a reason to choose one system over the other for my application?
My duct system will have a 1200 CFM capacity (new system). The Carrier has a 1220 CFM output on high heat. Could this cause a noise problem at the registers? There are 8 registers.
The Carrier apparently has 3 speed choices on constant fan, while the Rheem has 1. Is this a real advantage in my application? Does the Carrier use less electricity?
Both would be super furnaces. If you go Carrier, be sure to get the Infinity control and not waste the ability of a nice furnace with a single stage stat. Get the matching Mod stat with the Rheem.
The dealer can pick what fan on speed you use on the Rheem, choice of 2 I believe. Most pick 1/2 the cooling speed which usually is inaudible and draftfree. The Infinity control does let you change that yourself if you want to.
Personally I'm a Rheem fan. The Mod has been a super furnace both in comfort, quiet & reliability. All things being equal, no question go that way in my book!
As for air noise, depends upon what size pipe feeds those 8 registers and what size the registers are. If typical 6" runs, you will be hurting and things will be noisy with either furnace.
A month ago I had a Rheem mod furnace and stat installed. Couldn't be happier with it. It usually runs at low-fire, very quiet.
While both are great furnaces, they are better suited to long harsh winter climates with wide temp differences as compared to your relatively soft mild winter climate. I would look at a good two stg var speed 92+% AFUE furnace. That's all you need at the top. The other two are overkill.
What's overkill about them?
Seems to me a very mild climate is the perfect place to have a furnace with a 40% output like these 2 have vs 60-70% on low like a 2 stage has.