They're a LOT more expensive for the BTUs you get vs. a standard window unit. They're cumbersome to drag around, so they really aren't that "portable" when it comes right down to it. And they take up floor space. Another consideration is the power requirements. A 12,000 BTU AC will probably consume most of a standard 30 amp receptical circuit. Meaning that if you have it plugged in, you'd better not plan on running anything else off that circuit or you'll probably blow a circuit breaker. Some 12K units will even require a 20 amp circuit. For apartment dwellers, a couple of smaller lightweight 5K units that can be strategically placed in certain zones often makes more sense than a portable. It'll be cheaper, for sure. You can usually find a small 5k unit for under $150. You'll have less electrical load, especially if you only run them one at a time when you are in the specific zone. Yes, you'll have to pull them out and store them when cooling season is over, but you'd have to figure out storage for a portable too.

The larger the number of rooms that that you install mini splits in the higher the cost in comparison to a central system. Remember that you need returns for a central system. The choices are to have one in each room, install grates in between the rooms, install jump ducts or under cut the doors. Mini-splits have advantages in some situations. They are inherently zoned, so you don't have to cool the whole house for the dogs or you. Depending on your lifestyle, this might or might not save you money. What is installed in the USA is almost all variable-speed (inverter) equipment so it throttles well to control humidity under low load conditions. If you are on the costal plain, that is more important. It is humid down there. Typically, if a system fails you have lots of other areas to stay comfortable in. That also means that a modest generator will run parts of your system.) For me, a duct system that is outside of the house envelope is a drawback. First, ducts always leak even when new and they never improve themselves. That means everywhere you have a leak it equals a power vent either drawing in outside air into a return or blowing air outside. Keep in mind that also induces pressure differentials in your house so air is sucked in or blown out to balance that. Take a look at the Mitsubishi, Toshiba and Sanyo web sites and see what the mini split kingdom looks like. Keep in mind that in addition to the sterotypal high-wall indoor units, small ducted units (that handle more than one room) ceiling cassettes, horizontal ceiling units are available. You should see them on the web sites. They do cost more and are a little less efficient. Check out the different brands for how their controls thermostats) work if you decide to seriously consider mini splits. You obviously need more quotes given the difference between the two you already have.

Tigerdunes, I am having a 2.5 tom replaced. The home is 3400 sq. ft. but this AC is for the upstairs only, I'm guessing 12-1400 sq. ft. The thermostat is icomfort Wi-Fiî Touchscreen Thermostat Include Merv 11 air filtration system I have discussed the humidity with the HVAC company. I have no idea of the typical run tines, but it is NOT cyclling on and off. The reason for the replacement is multiple leaks in the condenser. They added 5 lbs. of freon to tide us over, to be recovered and credited back to up with new installation. Is there any other information I can provide. Thank you and this forum for any assistance. I am very grateful there is a place to go for people that are HVAC challanged (idiots like me). Christine

Hello, Would like to know how many BTUs (for 1 wallmount system)would I need for two floors of 690 sqfeet (each floor). The Unit will be on the 2nd floor in the middle between 2 bedrooms and a washroom (over washroom door facing master bedroom). It will be a dual split system. ------------------------------------- Also would like to know which is a safe reliable cost efficient brand, example of wall mounted (split systems) air conditions I've heard of: Fujitsu (they give 10 years warranty parts and labour) Mitsubishi (6 yrs parts and labour however been making them longer) Daikin (6 yrs parts and labour) Igloo York Carrier Grey All about the same price... ----------------------------------- Finally, is it better to get a dual system (with heat pump), from my understanding they are almost the same price and the advantage is that it has a variable BTU which may save some $$. Since the heat pump will be at the higher level then it wont heat as much however it is coming at about the same price. Then again more electronics in a system more chances of malfunctioning sooner? Thank you, Stelios