Carrier Infinity Touch Thermostat Software Update - Compressor Failure Soon Afterward

[MM704]

Model: 25HNA636A300 installed new in 2008
T-Stat Model: SYSTXCCWIC01-B installed 9/2021
Current Software Version: 131626-04.31
Previous Software Version: unknown (circa 9/2021 or prior)

I have two of the same model heat pumps that were installed new in 2008 in a split level house with legacy thermostats. They have provided good service with few needed repairs over the years and I realize they are likely near end of life. 9/2021 the main thermostat (2 zones for unit in question) failed, and due to supply chain issues local service provider could only obtain the newer Infinity Touch thermostat which installed easily and everything has worked fine since.

Last week the Touch thermostat displayed a message indicating it had a software update to install. Since it's connected via WiFi it performed the update without further intervention.

The very next day is when things started changing:
Day 1 (after SW update) noticed unit would start/stop very quickly. Like 3 seconds fan run time, then turn off.
Day 2 while unit was running a very noticeable rattling sound was coming from inside the unit
Day 3 a very loud humming noise was emitting while unit operated
Day 3 later in the day unit was operating normally with no noticeable oddities
Day 4 the fan ran continuously even though it should not have been running at all based on temps and settings.
Day 4 I received an email from the stat, 73-CONTACTOR SHORTED (Code: 73)
Day 4 service call placed, tech diagnosed as compressor failure

Service provider states compressor for this model is no longer available, so the recommended solution is to replace failed unit with Model 25VNA836A320 at a fairly significant price.

Coincidences happen, but it seems extraordinary that system failure occurs right on the heels of a software update. Having worked in software for many years I'm fully aware unintended consequences during updates are far too common. Given the totality of circumstances, I am hoping Carrier will provide some level of compensation towards the new unit cost.

Local provider suggested I call Carrier Tech Support, which I did. Carrier Level 2 support said they would contact the regional distributor who in turn would contact my local provider. That's been only about 24 hours; haven't heard from anyone yet. Meanwhile local provider has the new replacement unit delivered and ready for installation.

Here are my questions:
1. Given the fact the unit is 14 years old, does/should the story end there? Pony up and shut up?

2. Has anyone had similar experience resulting in any positive response from Carrier?

3. Does anyone know the particulars of accessing the data on that T-Stat? The event log via the UI displays only the last 10 events all of which are post-update. There's likely logs with enough data to illustrate operations before/during/after the software update that could bolster my claim with Carrier if I could retrieve them. I've internet searched (don't like the "G" word) considerably but have found very little other than the stat appears to run Linux. I can ping it, but have failed at connecting to it with various FTP clients and terminal emulators. Any assistance with retrieving those logs would be greatly appreciated.

4. Others have mentioned that a coil or perhaps entire air handler replace should be done with the new 25VNA836A320. The existing (installed 2008) handler lives in a climate controlled basement. Current service provider said handler should be fine. Thoughts on coil/air handler?

Thanks for any and all replies.

[rundawg]

Model: 25HNA636A300 installed new in 2008
Thanks for any and all replies.

Your unit (25HNA6) has the infamous Bristol Twin Single (TS) compressor in it, which has been well documented to fail within the first 10 years of service. Such so, that there was a Service Bulletin out for compressor or unit replacement if your unit failed within the first 10 years of installation.

Seeing as you are going into the 15th year, this bulletin will not apply to you, and you are very fortunate to have gotten the number of years out of it that you did.

With the known issues of the compressor in this unit, I seriously doubt Carrier will provide any financial assistance because the failure happened shortly after the time of the software update.

I know this info won’t make you feel any better, but it’s my 2 cents.

I do hope something positive will come out of your conversation with Carrier.

[BALloyd]

Those Bristol compressors fail mechanically in almost every instance that I have seen. Usually break a connecting rod. I highly doubt a thermostat update would have cause such damage over a short span.

Sent from my SM-S906W using Tapatalk

[FlyersFan]

I am also pretty surprised that your compressor lasted as long as it did. At one point during the warranty period Carrier was offering a new condenser in its place for a reasonable amount of money and homeowners had to sign a document declining the unit. Carrier kept those compressors until the warranties ended and wouldn't sell one on a unit that was out of warranty.

The software update didn't kill your compressor, the design did. Unfortunately if you have a second one I'd go ahead and start budgeting for a replacement.

As for changing the air handler or not - that's up to you. At 14 years old I'd consider it just to get the 10 year warranty if registered. It would suck to change the heat pump and then end up with an out of warranty coil leak in a year or two.

[kdean1]

The only thermostat that I know of that can kill a compressor is Nest.

[MM704]

All,

The information received from various sources has been quite consistent. Not necessarily better news for the wallet, but can take comfort in knowing I'm poised to make better, more informed, decisions. Thanks to you all!

[pacnw]

The only thermostat that I know of that can kill a compressor is Nest.

[pecmsg]

All,

The information received from various sources has been quite consistent. Not necessarily better news for the wallet, but can take comfort in knowing I'm poised to make better, more informed, decisions. Thanks to you all!

Now is the time to make any changes. Did the old unit cycle on and off when it was hot and humid? Probably oversized. Noise from supply and return ducts? Not maintaining a comfortable temperature and RH?

[Mr Bill]

If that compressor lasted 14 years, you must have the perfect install.

[MM704]

The old unit did not cycle on/off during hot/humid. Noise levels acceptable from all the equipment. Overall have been very satisfied with the comfort levels provided by this unit.

FWIW, the (same) contractor that installed these units 14 years ago was the only one of 3 bid contractors that bothered to come inside the house. Measured, asked questions, took notes; etc. Recommended zoning the lower 2 levels of the split level house, which has been the best thing ever. They also added more returns, increased the size of existing returns, modified some ducts and as a result for the first time ever the house is satisfactorily climate controlled. The failed unit serviced those lower two levels. Heat is supplemented with fireplace insert on the lower level. Proper cooling is easily achieved. I have an identical 14 year old unit with the Bristol compressor that services the third and highest level of the house. It does not operate nearly as frequently because that level is unoccupied for most of the day. Hopefully it will hang on long enough for me to get the first replacement paid for...

This time around contractor asked (did not site visit) about existing air handler and advised since it resides in a controlled environment it does not need replacing. Several other professionals have recommended replacing the coil at minimum, if not the entire handler. I will have that conversation with the owner when he is available on Monday. The new model 25VNA836A320 is being installed this afternoon. I don't want to save a buck at the possible expense of compromising the performance or lifespan of this new unit. It ain't cheap...

[MM704]

See below (was supposed to be a reply to previous post, but my forum-fu is weak...

My confidence level with this contractor is pretty high. They've provided good service for these past 14 years and seemingly did do a very good install. The techs that have PM'd over the years have commented similar in regards to the longevity of my Bristol compressors. Other customers have had as many as 3 replacement compressors within a much shorter timeframe so I guess I am truly fortunate in that regard.

I did an cost analysis (initial cost, PM, repair) and feel pretty confident these units (plus the other mods) have paid for themselves in utility savings. Happy to be shelling out big bucks right now? Of course not. Glad to know that statistically speaking I'm ahead of the curve? Heck yeah!

[ss120396]

I think you'll like the new unit. It will be much quieter, be able to turn down much lower at low loads, and take up much less space in your yard.