Lennox vs. Trane replacement system?
AC side of 14 year old Amana gas furnace/AC was pronounced dead in November. I have solar panels so I’m jumping off the cliff and going heat pump (and replacing gas water heater with a Stiebel Eltron heat pump water heater). The useful quotes I have are for a Lennox cold climate system (EL21KLV, proprietary communicating everything) or a Trane 6-speed (SEER 17.5 with Honeywell zoning). The Trane dealer bad mouths Trane zoning that I’d have to use if I went up to a Trane XV18 variable speed, saying he’s had to pull them out. I’m in Raleigh, NC, CZ 4A (one county over from 3A), 2050 square feet, two-story, completely straightforward upstairs/downstairs zones. I got an independent Manual J a few years back. It said I need 3.5 tons as is and 2.7 if I make some air sealing and insulation improvements (which I’m doing); so everybody is quoting 3 tons.
Every manufacturer seems to have lovers and haters. Many, many people say it comes down to the install; these are 4.9-Google review dealers. Nonetheless, my gut is calmer considering a Trane over a Lennox having read of parts-availability issues and the decade-ago class action against Lennox. Six-speed Trane with so-so 17° performance, better Trane the dealer doesn’t want to install, or go for broke with the Lennox? Surely Trane can manage two zones in 2025?
Thanks for your time and points of view.
Miles
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Replies
Instead of zoning consider making it a second system. It will cost more but you gain redundancy. Sooner or later when something fails you will still have 50 % capacity.
I think it is a mistake to ignore the installers reconditions and push them someplace they are not comfortable. Find a contractor who likes your plan or change plans.
I say forget about the fake Google reviews talk to you friends and neighbors.
The only thing I don’t like about my Rheem HP is that the fan blows out the top like the ones you are considering. When the conditions are right water from the roof drips on the stopped fan blades and freezes. Some times it prevents the fan from starting so I get no heat other times it spins but is unbalanced and shakes the unit violently. My next unit will be an Asian design with it sideways fan connected to a normal air handler.
You did not mention back up heat strips do you have the capacity in your electric service for them?
Walta
Like Walta says, what matter is the unit the installer is comfortable with.
I'm also partial to the Asian style outdoor units plus these have a much longer track record. I would see if there is a local carrier installer that can quote you a Carrier 38MURA / 40MUAA combo. Those come in two flavors, make sure they spec the high heat unit. The only difference between the two is one letter in the model number so easy to mix up and the low temperature output is significantly different between them.
A Carrier dealer checked with Carrier Tech Support today and was told that the 38MURA / 40MUAA combo "can not be zoned at all". We tried!
Thank you both for your insights.
My house is 50 years old; the existing system is in the crawl, return and supply for the upstairs run through a chase in the chimney. Ugh, plus another ugh for ducts in the attic.
I like the redundancy of two systems but the logistics would be quite a challenge. I have no idea if anyone would or if it would make sense to run the upstairs unit from the crawl. re: power for strip heat, I will be replacing/re-energizing an abandoned subpanel in the crawl for strip heat there. I've learned as part of this exercise that Siemens has a line of breakers that provides a pair of two-pole breakers in a single, two-slot package. This part of the project would have gotten expensive otherwise.
Another complication with two systems: splitting the 3-ton load. I think it'd be an interesting science experiment to have a cold climate 2-ton for the downstairs paired with a cheaper 1-ton for upstairs. But reality is complicated enough for me, I won't go there.
One person quoted a Bosch system (which I thought was side-discharge but now I think not). I had no idea they were in HVAC.
I've requested a quote on the Carrier units Akos suggested.
Again, thank you both.
Miles
It seems like both units you have spec'ed seem pretty low end for current technology. I have a 2 ton Carrier infinity 24 SEER inverter HP for a 1550 ft2 house in Central Texas (2a) plus a 28 SEER mini split for my garage / shop. They are incredibly efficient and even during 100+ summer days still operates on low speed so I get really great dehumidification. My Greenspeed operates for about $2.50/day on the hottest days keeping the house at 71.