"That means he could twist his words after executed the contract with me?" If you were buying a new Honda Accord, would you accept that no specific model number was put on the sales contract (ex. LX, EX, EX-L, 4 or 6 cylinder)? It is the same thing in HVAC equipment. You are paying for a specific size and model for each piece equipment. Perhaps you trust the HVAC contractor to do the right thing, but more often than not it does not happen. If you have low humidity (less than 30%) then you may want to invest in a humidifier, otherwise you don't need.

OAKRUNFARM I understand what you are talking about I too received my qoute today for a home that has 1500 sq ft on the main 500 upstairs and 1500 sq ft walkout basement our quote was roughly $20K . Now I understand Trane makes the top of the line system but our second highest quote was for a tempstar and that was $12k . I was told by a gentleman that installs hvac systems ( not trane) that the systems I was quoted was easliy $5k to high. my questions to the hvac folks here especially the TRANE pros do these prices sound realistic and are they negotiable? we had our hearts set on a trane system, but now Im not sure. Good luck to you on your build.

WHAT IS A HIGH LIMIT SWITCH? https://www.newcentralairconditioner.com/ The high limit switch in your gas furnace is a small part with two very important jobs. This switch plays a role in the normal operation of your furnace. Turning the fan motor on and off is the high limit switch’s main job. This is the role it plays in every cycle of your furnace’s normal operation. But that’s not the only thing that the high limit switch does. It’s also safety device that helps prevent your furnace from overheating. The high limit switch consists of a long temperature-sensing probe attached to a metal mounting plate. From the mounting plate, the switch is wired to the blower fan motor and to the gas valve. The switch is generally located just past the heat exchanger. This is so that it can detect the temperature of the supply air. In other words, the air that’s about to be blown into your home.

Sizing can be less of an issue when you have multiple units. Because each unit is controlled independently, provided of course the unit itself is not over sized for the area in which it serves resulting in excessive short cycling. In your case 3 ton plus 2 ton isn't necessarily equal to 5 tons of cooling... unless you drive those thermostats really low. By having two systems with total capacity of 5 tons (which, most of the time this would be oversized for a 1700 - 1800 sq ft structure) has a few advantages. 1. You have the ability to use one system only during low heat days or set the opposing unit higher. The unit set higher only runs if load conditions warrant.... meaning if it's not hot, the thermostat controlling the unit does not call... the unit can not run without a call... 2. Utility bills can be much less... because you rarely use both systems at the same time. You run the bedroom system when you sleep, the other when you're awake. If you have a home office in one the bedrooms you may need to rethink things a bit. 3. Extra capacity for when it's hot out. When it's hot you have the capacity to cool the home. (even while entertaining guests --- additional people add heat) Remember heat waves come, heat waves go... a so call 'properly sized' AC system is essentially properly sized roughly 10% of the time... especially if that system is a single speed AC system. Alot of people I come across like to sleep cool. So for that reason I doubt I would change the configuration of the space. Once you realize what you have, the choices you make are mostly budget type concerns. Essentially a set up like this runs like a 2 stage system. This kind of subject is above the pay grade of many... choose your contractor wisely. I service the Katy, Texas area.