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kevin588127

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Discussion starter · #1 · (Edited by Moderator)
I have a 13 year old Lennox heat pump in nothwestern Iowa. Recently, Ive replaced the blower motor and a defrost board. This has me thinking about what will fail next and thinking of its eventual replacement. I am also hearing 410A will be a thing of the past. Due to the nature of the install in my home, replacing the air handler and line set would add some complexity. My air handler is electric backup and with the blower motor replaced, the only other failure point is the board or the heat strips. My thought was to just replace the evaporator and condenser coil. I contacted the dealer that installed the original and he somewhat agreed with my thought process. He spec'd me out a new 3 ton A coil and 3 ton condenser, still single stage. Existing coil and condenser are 2.5 ton but the system seems to struggle on the heating side of things, even in moderate weather. The quote came back quite a bit higher than I expected for just replacing the A coil and condenser. He also quoted me a complete new unit with variable everything. Only about *** more than reusing my existing air handler.

So here is where I'm at: spending **** to replace a unit that is at this point, functioning fine, seems foolish. If I wait, and the unit fails, I will be looking at higher equipment cost and higher install costs. I've also not been a huge fan of lennox or the install of the existing unit. There were lots of problems early on with the unit and I feel it has never really performed great.

My options as I see it:
Go with the replacement lennox components.
See if another company can fit another brand A coil and condenser into my existing air handler.
Wait until the next major failure and deal with it then.

Some other relavent info:
The home is half earth home, half above grade. The earth home portion of the home is very easy to cool but hard to heat. The above grade portion is spray foamed with lots of attic insulation. The earth home portion has electric baseboards that have gone unused since installing the heat pump. We have tiered electrical rates. The more you use, the cheaper the rate gets. for this reason, I often question if the heat pump is even worth it. Due to the type of home and the climate of nothwest Iowa, the heat pump really only operates in Nov, Feb, March and part of Apr. Dec and Jan are usually too cold, and we are operating on electric backup.

Any suggestions are greatly appreciated.

Please do not add pricing to your posts as it is not allowed by forum rules - thanks.
 
#2 · (Edited)
Manufacturers suppose to stop production of R410A outdoor units 12/24. Chances there are still many at supply houses already throughout the USA. Not sure but some manufacturers may produce dry charged ( filled with a holding charge of dry nitrogen ) outdoor units after 12/24. Some manufacturers did that when they phased out R22 equipment.

R410A refrigerant should be around for a bit, but at some point in the near future the actual production will be decreased year after year until production is ceased.

You’re paying for the name with Lennox to a degree. No manufacturer makes much of their equipment nowadays, as an example the outdoor unit, manufacturers make the painted sheetmetal box and the coil at best. The rest of the parts are by others. The heart of the system the compressor is made by others, the reversing valve assembly, capacitors, fan motors, fan blades, compressor contactor, circuit boards, etc are by others. Same with the Air Handler, the painted sheetmetal box and coil assembly, that’s about it.

It will not say Made in the USA anymore, at best assembled in the USA or Mexico or if it does say Made in, it probably will say China.

Get a AHRI matched system if you go existing Air Handler and new uncased coil to outdoor unit of any brand. Keep it simple a single stage outdoor unit and a lower SEER2 line. Chances the coil hook up of the new coil will not line up with the existing holes of the existing hookup for the lineset. Also the drain line section may be in a different location compared to existing, so new holes need to be cut in the access panel and even for the drain line.

A three ton coil, may/may not fit ( height wise? ) in a 2.5 ton rated Air Handler. You may need to look up the specifications sheet of your existing Air Handler if it’s a 2.5 ton and wanting to put a 3 ton rated coil in there as the blower wheel assembly on the 2.5 ton Lennox Air Handler may be smaller than the blower wheel assembly on a 3 ton Air Handle of those years ( 13+ years ago ) even if they are the same width and somewhat similar depth and dealing with a Heat Pump, that can easily create issues? Who’s to say your existing ductwork is even rated for 2.5 tons, maybe it’s rated at 2 or 2.25 at best and putting in a 3 ton coil in there is hmmm.

Or ride it out with your existing system,..

Right or wrong that :.02: worth of free advice..

Decisions,..Decisions..such is life.
 
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#3 ·
kevin588127 said:
I have a

13 year old Lennox heat pump in Northwestern Iowa.

Recently, I've replaced the blower motor and a defrost board.

This has me thinking about what will fail next and thinking of its eventual replacement.
I am also hearing 410A will be a thing of the past.

Due to the nature of the install in my home, replacing the air handler and line set would add some complexity.
My air handler is electric backup and with the blower motor replaced, the only other failure point is the board or the heat strips.

My thought was to just replace the evaporator and condenser coil.

I contacted the dealer that installed the original and he somewhat agreed with my thought process.

He spec'd me out a new 3 ton A coil and 3 ton condenser, still single stage.

Existing coil and condenser are 2.5 ton but the system seems to struggle on the heating side of things,
even in moderate weather.

The quote came back quite a bit higher than I expected for just replacing the A coil and condenser.

He also quoted me a complete new unit with variable everything.
Only about *** more than reusing my existing air handler.

My options as I see it:
Go with the replacement Lennox components.

See if another company can fit another brand A coil and condenser into my existing air handler.
Wait until the next major failure and deal with it then.

Some other realevent info:

The home is half earth home, half above grade.

The earth home portion of the home is very easy to cool but hard to heat.
The above grade portion is spray foamed with lots of attic insulation.

The earth home portion has electric baseboards that have gone unused
since installing the heat pump. We have tiered electrical rates.
The more you use, the cheaper the rate gets. for this reason,

I often question if the heat pump is even worth it.

Due to the type of home and the climate of northwest Iowa,
the heat pump really only operates in November, February, March and part of April.

Dec and Jan are usually too cold, and we are operating on electric backup.

Any suggestions are greatly appreciated.
[/COLOR]
Click to expand...
Modes of OPERATION
NEED TO BE REVISITED.

Heat strip(s) provides the AUXILIARY HEAT Function.

APPARENTLY, the heat strip is NOT SET-UP in the usual manner.
 
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Discussion starter · #4 ·
dan sw fl said:
Modes of OPERATION
NEED TO BE REVISITED.

Heat strip(s) provides the AUXILIARY HEAT Function.

APPARENTLY, the heat strip is NOT SET-UP in the usual manner.
Click to expand...
Not quite sure what you are saying here so I'll clarify how I understand the sytem to work:

Stage 1 is my heat pump. It operates under normal conditions. In the event that the heat pump runs for 300 minutes and still doesn't satisfy, Stage 2 pulls in. stage 2 is 10Kw of my heat strips. If the system runs for another predetermined amount of time, the 3rd stage pulls in. This is an additional 5k of electric.

When the outside temps are below 20F, The heat pump is bypassed all together and I am running on Aux heat all together. There are very few days in Dec, Jan and Feb where we see temps that allow the heat pump to operate much at all.

Initially, there was no temp lockout on the heat pump. We noticed that it was running excessively during the coldest months and had this change made. Due to the way our utility company charges for power, the excessive run time of the heat pump provided little savings vs the wear and tear on the heat pump.

To explain a bit further, our utility charges $.20 per Kwh for anything under 1000 kwh. Everything after that is $.03 for heating and cooling appliances ($.06 for non heating items). Any Kwh saved between electric heat or the heat pump is only at $.03 per Kwh. It is the dumbest rate system I've ever seen but it is what it is.
 
Discussion starter · #5 ·
Bazooka Joe said:
Manufacturers suppose to stop production of R410A outdoor units 12/24. Chances there are still many at supply houses already throughout the USA. Not sure but some manufacturers may produce dry charged ( filled with a holding charge of dry nitrogen ) outdoor units after 12/24. Some manufacturers did that when they phased out R22 equipment.

R410A refrigerant should be around for a bit, but at some point in the near future the actual production will be decreased year after year until production is ceased.

You’re paying for the name with Lennox to a degree. No manufacturer makes much of their equipment nowadays, as an example the outdoor unit, manufacturers make the painted sheetmetal box and the coil at best. The rest of the parts are by others. The heart of the system the compressor is made by others, the reversing valve assembly, capacitors, fan motors, fan blades, compressor contactor, circuit boards, etc are by others. Same with the Air Handler, the painted sheetmetal box and coil assembly, that’s about it.

It will not say Made in the USA anymore, at best assembled in the USA or Mexico or if it does say Made in, it probably will say China.

Get a AHRI matched system if you go existing Air Handler and new uncased coil to outdoor unit of any brand. Keep it simple a single stage outdoor unit and a lower SEER2 line. Chances the coil hook up of the new coil will not line up with the existing holes of the existing hookup for the lineset. Also the drain line section may be in a different location compared to existing, so new holes need to be cut in the access panel and even for the drain line.

A three ton coil, may/may not fit ( height wise? ) in a 2.5 ton rated Air Handler. You may need to look up the specifications sheet of your existing Air Handler if it’s a 2.5 ton and wanting to put a 3 ton rated coil in there as the blower wheel assembly on the 2.5 ton Lennox Air Handler may be smaller than the blower wheel assembly on a 3 ton Air Handle of those years ( 13+ years ago ) even if they are the same width and somewhat similar depth and dealing with a Heat Pump, that can easily create issues? Who’s to say your existing ductwork is even rated for 2.5 tons, maybe it’s rated at 2 or 2.25 at best and putting in a 3 ton coil in there is hmmm.

Or ride it out with your existing system,..

Right or wrong that :.02: worth of free advice..

Decisions,..Decisions..such is life.
Click to expand...
I had the estimator out from the original company. Lennox makes a 3 ton coil that will fit in the existing air handler and everything will line up. The duct work is 2 14.5" trunk lines, each feeding 7 6" drops. The ductwork was installed at the same time the original lennox unit was installed. He made no mention of it not working with the 3 ton unit. The air handler has a variable blower motor in it if that makes a difference.

For reasons you mentioned, I have no problem ditching the lennox name. I do like the air handler because it is in place and I am familiar with its operation and servicing it. Its simple and has some new components in it. Any sugestions on who makes a decent condensor?

I did price out the lennox components that were quoted to me. I can get them myself for about $4500 and I suspect the contractor can get them cheaper. I have no problem with people making money, but 4k for a day of labor seems a bit steep. That has me looking at other options. Thanks for the advice you have provided.
 
#6 · (Edited)
Again a 3 ton coil may fit your 2.5 ton rated Air Handler, but the blower wheel may/may not be rated for 3 tons meaning it could be smaller in depth/length and width. Reason for checking a 3 ton Air Handler Specification sheet of the same Air Handler as what you have but in a 3 ton model to see if the blower wheel is the same dimensions.. make sure the 13+ year old blower wheel is squeaky clean also, have your Contractor wash it out if there is accumulation on it.

Again who knows if your ductwork is even rated for a three ton system, let alone a 2.5 ton?

“There were lots of problems early on with the unit and I feel it has never really performed great”

“Existing coil and condenser are 2.5 ton but the system seems to struggle on the heating side of things, even in moderate weather”

Maybe you got an inferior install and setup and inadequate ductwork layout and sizing, kinked lineset etc. etc. more than anything else?? Can’t tell from here..

What makes you think going larger coil and new outdoor unit will magically fix your issues?

Have your Contractor check your static pressure before and after installation of the more meatier 3 ton coil to see if it’s within manufacturers guidelines. Rots of ruck, probably never get done/checked.

Heat Pumps are more critical ( in heat mode ) needing to get proper air flow across coil. But hey, throw a 3 ton Lennox coil in the existing Air Handler and get a Allied Air or Concord outdoor unit or another Lennox brand under their umbrella and have your Contractor shoot for a AHRI matched system, ( coil to outdoor unit ) and let us know how it works..
 
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Discussion starter · #7 ·
Thanks for the reply. A few other things to add. This contractor sized everything during initial install. I believe they said they said it was a 3 ton capable air handler at that time. This most recent estimator said he was going to contact Lennox and get it from them that the coil and condenser would be compatible.

As for the problems it has. It would randomly lock out on high head pressure. Several techs looked at it. The third one finally fixed it by installing a low ambient kit, I believe. Who knows what else was done but it worked since with no issues.

As for underperformance, I think it is mainly due to the home itself. The main portion of the home is earth sheltered. Its concrete floor, walls and ceiling with the insulation being installed on the outside. Insulation from 1983, lol. Lots of thermal mass that wants to be ground temperature. As we have remodeled, I have been firring out walls and adding blue board insulation. All this to say, the spray foamed addition that I added heats and cools much differently than the earth sheltered portion.

Again, thanks for the replies. I'll definitely be asking better questions regarding the duct sizing if I decide to get more quotes.
 
#8 · (Edited)
What’s the model number of your existing Air Handler and outdoor unit?

“As for the problems it has. It would randomly lock out on high head pressure. Several techs looked at it. The third one finally fixed it by installing a low ambient kit, I believe.”

Low ambient kit? How does the low ambient kit help lower a high head pressure condition, what does the invoice say? Are you talking about the high head pressure was in cool or heat mode?

To me a low ambient kit is used on the outdoor unit in cool mode when wanting to run the A/C in real cold weather, such as maintaining a certain room temperature in a Computer Room year round, or thereabouts.

Even if you can get your Contractor to do a before and after static pressure checks, they can easily fudge the numbers, especially if it’s not within manufacturers specs. , but hey if your not worried about possible shortened blower motor life so be it..

Did you mention to them about doing a before and after static pressure check, guessing they said you don’t need one? Read up on static pressure and the correct position for the probes to take the reading.

Make sure to register your new coil and outdoor unit of choice as manufacturer warranty decreases if system does not get registered.
 
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#9 · (Edited)
“The earth home portion of the home is very easy to cool”

Going a bigger unit to 3 tons, will your A/C short cycle now, or even more, meaning it will not run as long as your existing system, meaning will it still remove the RH as well as the 2.5 ton? If your 2.5 ton did a good enough job at that.

Does your return duct and/or wall opening need to be a little larger due to going larger coil?
 
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Discussion starter · #10 ·
Return air is wild, which seems to work well due to the open concept floor plan of the house.

Humidity is another challenge of this house. Even with the AC cycling as what I would call normal, we still run a dehumidifier to keep the levels below 40 percent. I would like to add a whole house dehumidifier with a fresh air inlet.
 
#11 ·
kevin588127 said:
Return air is wild, which seems to work well due to the open concept floor plan of the house.

Humidity is another challenge of this house. Even with the AC cycling as what I would call normal, we still run a dehumidifier to keep the levels below 40 percent. I would like to add a whole house dehumidifier with a fresh air inlet.
Click to expand...
It cycles because the A/C is oversized.

Shutting the heat pump off below 20°F is wasting electric. The absolute worse a heat pump gets is 1.1 -1 with straight electric being 1.0.
 
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