Cambridge installed a mini split heat pump system for my home. The initial install went okay, but they did not cover the floors, fully clean up, and one guy used my tools without asking. This winter, we have 2 problematic rooms using ducted mini split. When outside temps were in the teens, the ducted mini splits heated to 60 degrees, unable to reach the set point of 72. With outdoor temps of 30's, the room temp is 4-6 degrees under 72. They sent 2 techs to troubleshoot the thermostat. It initially read 68. After they tinkered with it, it displayed 74. My other room went from 54 to 59. They said they had to go into the advanced settings to make it warmer. Great, as long as it works. I looked into the manual after and found a setting called Indoor Temperature Display Offset which allows you to add or subtract 5 from the room temperature display. I checked the setting and turns out the techs just changed this setting to make it seem like the room was warmer than it actually was by adding 5 to the display. Shady work. I eventually got Dave and Tom on the phone. They were defensive and tried to discredit my concerns. Tom said it is normal for a 5 degree difference. I called Mitsubishi and they told me that was a lie. About the room temp offset, Dave aggressively said it is impossible (it's in the manual), and illegal to do that, and that all the techs did was resync it. Then why was the offset at +5? I did a resync myself to see if that changes the offset to +5 - it doesn't. Dave asked me about room insulation and air sealing - which I then asked if isn't all of that considered when sizing the system? Dave got really offended and proceeded to condescendingly lectured me about how he does a manual J calc for every project. I'm just a home owner trying to understand why his room isn't being heated well - why is that unacceptable to ask? I asked Dave what my options are. His response: Turn up the thermostat (hah). In the end, they said they would send a tech out. Weeks later and no attempts to fix this issue. So much for that 1 year warranty. Mitsubishi recommended to get a different guy to come as they had doubts about the installation. And wow were they right. The ducted units had amateurish duct work - full of inefficient bends, creating a high external static system that restricts air flow - the main reason why the rooms weren't heating well. They are supposed to operate in low static pressure, and the new contractor said it should look more like this - [*** Link removed ***] Night and day comparison to the way Cambridge installed my units (see attached images). He had major concerns for one outdoor unit on the NW side. It was low to the ground and snow and ice can affect it. There was no wind guard on it, and the winds usually come from the NW, which can trigger more defrost cycle. Boy was he right... Yesterday (20 degrees, snowy, windy), there was ice on the lower coils for most of the day. The condensers were in defrost cycles every 15 minutes of run time, for 10 minutes at a time! During those times, there is no heat being generated. My home was at 62 degrees the entire day with the fireplace in use! I even asked Dave during the install if snow would be an issue and he said to just shovel it. What a tremendous understatement that was! Thanks Cambridge - for taking tens of thousands of dollars just to heat my home to sub 60. I don't expect or demand any resolution from Cambridge, and am cutting ties with them completely (I doubt they would even come at this point anyways). I've lost complete trust in them. What I should have done was just pay slightly more for a more competent company that actually understands the intricacies of properly heating a home. If you're trying to use these heat pumps as your main heat source, I suggest you do the same. But if you're just getting mini splits for cooling or supplemental heat, I think you can get by with their workmanship if you really wanted to.