Hello folks! This is my first visit to this forum, but it looks like I've come to the right place. I'd like to get a little information about a problem I'm experiencing with my Carrier heat pump system. Last weekend, I noticed it wasn't working, and traced the problem to a tripped breaker on the 24V transformer in the air handler. I reset it, and them powered up the system -- as soon as I did, a plume of smoke came out of the thermostat! I shut the thing down, and examined the components of the thermostat (it was one of those mechanical, mercury-switch types), and saw a coil of wire (looks the windings inside a potentiometer) near the bottom that was charred. A Heat/AC contractor came out and replaced the thermostat with one that I picked up at Home Depot (a Honeywell RTH7500). My wife supervised the install, and when I got home from work, I tried it out and found that it didn't work! The t-stat would display "Heat On," but nothing happened. Upon reading the manual, I checked the configuration and found that the guy didn't set it up to run a heat pump -- he just left it at the factory default! Now how he "checked" it when he was through is beyond me ... but I set to "Heat Pump with Auxiliary Heat," and it took off. Sort of ... It would only run for about 30 seconds, and then it would shut off -- the t-stat displayed "WAIT" -- after 5 minutes, it would run for another 30 seconds, and then "WAIT" again, etc. etc. The tried the "Emergency Heat," and that wouldn't run at all -- it would try to start, and then the t-stat immediately said "WAIT." So, the guys came back out, and now they claim there's a "bad board" in the compressor unit. OK, that makes a little more sense, rather than the old t-start just going up in flames on its own. I'm waiting for them to come out with a replacement, but in the meantime, I was wondering why the "Emergency Heat" won't run if there's a problem with the compressor? I thought the compressor wasn't used in that mode? Or is one of the boards in the compressor unit responsible for controlling the system in the "EM Heat" mode? For what it's worth, even though neither "Heat" or "EM Heat" work, the system runs fine in the "Cooling" mode. Thanks for any insight anyone can provide about how this all works!

Hi there, I have a carrier HP, model 38YXA024-3, and an air handler FV4ANF002 without strip heaters. I would like to upgrade my system with strip heaters and have already run all required wires to the handler, temp-sensor, and old thermostat (TSTATCCNHP01-B). I would like to buy something smart and have eyed with the TSTATCCTRH01-B and the KFCEH2601C10 strip heater. This was also recommended by carrier. However the KFCEH2601C10 is not staged (I think), and here is what I really want. Can someone tell me if that makes sense and what I should use? I want: (1) if outdoor T>42F, then HP only, with optional 1st stage timed, maybe other stages too. I want to be able to adjust the time trigger and temp switch point to adjust for the size of my home and kWhrs drawn for each degree increase compared to kWhrs drawn by the HP for each degree. (2) if T<42F, then HP with stages triggered by some algorithm (3) if T<32F (or so), then HP off, but eHEAT stages triggered by some smart algorithm. Or does one leave the HP on even at temps below freezing? (4) if T<0F or so, then HP off, eHeat off, but oil furnace on. (5) Next year, I want to put zones into THAT ! Anyone know of a TSTAT/StripHeater combination that can do that? Thanks - Thomas