I have two Trane units (installed 2008 and 2009 with complete systems including brand new furnaces). both are gas for heating. My 2009 unit (R410A) has variable speed for gas furnace. It has a rather odd behavior. When I was in attic installing EZ-trap, I noticed it. I turned off AC from T-Stat. But every a few minutes, the blower would blow and fire flames are burning. First, I thought it was because I was touching the system and tripped something. but I was observing a few times later without me touching anything. How can this possible? For one, it's summer and I don't need heating. secondly, how can it operate without T-Stat turned on? the other unit (R22, installed 2008) doesn't have the same issue. I wonder the system 'leak' gas and furnace has to burn it?

Hi, I purchased a Mitsubishi - MZ-FE18NA. I have drilled the holes in my walls and am about to run the copper lines. I noticed that the indoor unit has some copper attached to it. 3/8 and 5/8 lines, about 2 feet long. It makes sense that this extension is pre-attached as it will make installation so much easier, but the manual doesnt mention it--either did the guy I spoke to at the place I bought it. So, I guess, when I hang the inside unit, I just put the extensions through the wall and make the connection nice and easy on the outside. I just thought that one of the goals was to have as few connections as possible and that the lineset should run from compressor to indoor unit with no fittings (if possible). Of course, these pre-installed extensions will make it MUCH easier. That is what they are for, right? Also, on these pre-installed extensions, I would have expected a regular flair and nut on each line. But it looks like there is some sort of a ball on the end--like you would see inside a ball valve. so, now Im a bit unsure as to if this is a simple flare connection. Does anyone have any experience with these?