Carrier Infinity Thermostat Freezing my Pipes

[hvaccraig3]

My renovated vacation home was updated in 2014 with a Carrier Infinity system (2-stage HVAC). Since the home gets very cold in the winter and I cannot be there year round, I "winterize" the plumbing completely (flush all water from the pipes and turn off the water supply). The Infinity WIFI thermostat was at first a welcome addition since I can use the mobile app to monitor the system and house temperature leading up to winter.

Since the system was installed, I've had a few instances where the thermostat reboots (presumably after a power outage) and instead of resuming operation goes into something like a reset or install mode. On these occasions, I got an email notification that the thermostat has lost connection to the WIFI. What I am not told is that this "reset" disabled heat calls and left the home without any heating/cooling. Two years ago, this problem occurred one week before I could fully winterize the house and I had frozen pipes burst inside one wall (thankfully I still turned off the water main). The house was 40 degrees inside. The thermostat seems like the Achilles heel of the system and it led to an expensive mess.

This year, a few days before my annual winterizing, I was notified at home that once again my vacation property thermostat lost connection to the WIFI. I confirmed the house had active internet, so the problem was at the thermostat. With below average temperatures at night, I made an early trip to the house to make sure there was heat. Upon arrival, I found the house freezing inside and the wall unit display as shown in the attached images:


The first picture shows the first thing I saw when I inspected the wall control. It resembled the installer sequence - or something like it. I didn't care- the house had no heat like the last incident and I had to hope no pipes burst in the previous cold nights. Miraculously, none did but when i reset the thermostat and the display came up (second picture) you could see the house was 47 degrees inside on the 2nd floor. The first floor, also heated by the same furnace felt much colder.

While at the house later, I witnessed a brief power outage (not sure why). I took the opportunity to watch the thermostat, and it powered up and resumed operation without issue. High winds here can knock out power, but thermostats I've owned before could handle it with or without battery backup. My Carrier dealer did not know if I could switch out to another thermostat, but based on other forum posts it looks like the Infinity model is necessary to get all the efficiency functions of the HVAC units.

So my question: What options do I have to ensure the furnace never loses connection to its wall control? I honestly felt better when I had the 30 year old Honeywell thermostat from the previous furnace. I like the WIFI , etc. but the most important thing I need is HEAT when I'm hours away from the property. I spent a ton on this equipment, but it's got an Achilles heel for a wall control.

Some details:
1) I have the latest firmware (always)
2) Thermostat Model: SYSTXCCITC01-A (installed 2014)
3) Infinity HVAC models (don't know but they are 2-stage and run great when the t-stat works)

[beenthere]

I'd switch to a regular wifi stat. While the Infinity control has a lot of features over a regular 24 volt thermostat, burst pipes cost more than what that control gets you.

[pacnw]

I would get in contact with Carrier or a local certified dealer and find out if this is a defective UI(stat).
Also, determine if the new version of this UI does the same thing. If not, a switch to it may be in order. Depending on age, it still may be warranty.

[hvaccraig3]

Thanks for the response. I am aware that the Carrier infinity server has been down for days, and as another forum member mentioned, their website now informs you of this. It did not show a message last Friday when I first suspected the issue.

***Moderator: I am unable to respond to another thread from a member who is new to the forum. He mentioned he also cannot reply to threads, including mine which he referenced. Is there a limitation on user access for posting replies?

[martyinlincoln]

Only pro members that have been approved to post in the AOP forum can respond to threads.

[hvaccraig3]

Appreciate the reply. I looked up my warranty and the unit is still covered. I called my dealer, and they said they would order me a replacement, but instead of model SYSTXCCITC01-A I will be getting the updated model SYSTXCCITC01-B. My dealer informed me that while the unit is covered under the warranty, installation and shipping is NOT COVERED so I am on the hook for a couple hundred bucks. Not happy about that.

I am hoping this revised model will not get stuck during a power-outage reboot and cost me more in burst pipes.

[ckartson]

You may want to have your HVAC contractor add a "low limit" thermostat set to maybe 50°. This at least will prevent freeze conditions during a thermostat outage. This could be done pretty inexpensively and could probably be mounted somewhere near the equipment so it's out of the way.

[ckartson]

Google construction thermostat. These have fixed setpoints

[ckartson]

I'm not suggesting you run out and order this. I'm suggesting that you talk to your HVAC contractor about feasibility.Good Luck.