Quote Originally Posted by jjnet View Post
Equipment: New 3 ton Trane XL19i 2 compressor heat pump with matched variable speed air handler and 9.6kw 1410 single-circuit one-phase 240v backup strip heat. Trane residential zoning (6 zones) and electronic air filter. Ducting per Manual D based on HVAC-Calc load, oversized somewhat for zoning. 8” bypass duct (per recommendation of JR Benny on this forum) can be either routed to the return plenum or dumped to basement hallways.
You system sounds almost identical to mine, installed in 2004: Trane XL19i, variable speed air handler, six zones, one difference is I have twin heat strips at 20 Kilowatts and the eletrostatic filter. My installer used the Honeywell zone board. Which are you using? And the small compressor on my unit failed after 4 years of service and I have had to replace all of the zone damper motors at least once, and in several instances twice. The heat strips were replace after four years and again just a few weeks ago due to the failure of the over-temp fusible links.

My system has always be very expensive to run in the heating mode and just this week I installed a multichannel power monitor (www.brultech.com) to see if I could figure out what was going on. Much to my horror I found that the system has been doing much of it's heating using the heat strips (both of them), and the small compressor was being cycled on and off every couple of minutes for hours on end. I suspect the system has not been set up properly. As an electrical engineer I very comfortable with instrumentation but I don't know beans about "real HVAC".

I'd be very interested to hear your experiences and any suggestions on how to find someone that can diagnose my problems.

I must confess to have lost all confidence in the company I've been dealing with. thanks, -john-