Outdoor Fan Motor -- The outdoor fan, also called the condenser fan, is exposed to external conditions. As such it is most prone to dust and debris and the extreme weather. In desert climates, the outdoor fan motor is subject to heat not only from normal operation but from the outside temperature as well. As it starts to fail, the fan may work fine in the cooler morning hours but stop by afternoon. This can shut down the entire system for hours. When they stop running completely, your air conditioner will no longer work. Running a faulty fan will lead to compressor failure, which is a very costly repair.
The use of furnaces, space heaters, and boilers as a method of indoor heating could result in incomplete combustion and the emission of carbon monoxide, nitrogen oxides, formaldehyde, volatile organic compounds, and other combustion byproducts. Incomplete combustion occurs when there is insufficient oxygen; the inputs are fuels containing various contaminants and the outputs are harmful byproducts, most dangerously carbon monoxide, which is a tasteless and odorless gas with serious adverse health effects.[14]

HVAC is an important part of residential structures such as single family homes, apartment buildings, hotels and senior living facilities, medium to large industrial and office buildings such as skyscrapers and hospitals, vehicles such as cars, trains, airplanes, ships and submarines, and in marine environments, where safe and healthy building conditions are regulated with respect to temperature and humidity, using fresh air from outdoors.
They are also often harder to install. A proper location on the roof must be selected that can support the weight of the unit. Then a platform must be built and a drain pipe for the unit must be run along the roof to avoid problems with mold and corrosion. A crane must be used to lift the unit onto the roof while a team guides it into place and hooks it up.
Installing a split system may involve making modifications to the house itself for the necessary lines to be run. The heat exchangers are also more prone to picking up debris and must be cleaned on a regular basis. While they come with protective screens over the fan, care must still be taken to ensure that nothing gets in, especially in a home with children.

Typically speaking, the lower SEER, more basic models are also more reliable.  Reliability is big with us, so we steer clear of features with reliability issues, and it’s as simple as that. When you factor in the price of repairs and the extra expense of the 21-SEER, you may actually lose money! 16 SEER is the sweet-spot, and it is key to reducing your HVAC installation cost.

As for the price I think my review was fair in stating what value we got for what I deemed to be a slightly higher price than others might charge.  I did not take any stars off for the price, and still am not, but I am taking another star off because of Alberto's comments, which are deceptive and not the same thing he told me in person.  Alberto, I suggest you stick with the high road in the future.


We bought 2 top of the line Lennox HAC for $29,000 less about $3,500 rebates, thinking they would at least last 10 years. Well, after 6 years, the system leaked. We are paying $1,700 to fix that leak. We thought at least it is still under warranty - yes BUT - the warranty covered $15 & the rest we were up for ,even though they advertise 10 year warranty. We are trying to sell & move out of high cost southern Calif & have looked at 20+ places in Arizona. Most of the houses we looked at were built from 1998 to 2005. We asked if the HAC was original & in most case it was - even though the highs were 115 to 120 & the lows 90F - versus where we live the highs run 85 to 95 & the lows are in the 60s. I asked the repairman WHY ours went out at 6 years. He replied that they just do not build them the same anymore. In Arizona, I did not see any Lennox - mostly Trane or Carrier. We had Fujistu in Australia which were fantastic - nothing went wrong in the 9 years we had them. Also, they had full induction motors not like the energy consuming 2 stage motors in Lennox. Maybe the Japanese built Fujusita still builds quality & the warranty is meaningful?

You might also want to check your home for thermal insulation if you live in extreme heat or freezing temperatures. Insulation keeps the heat and cool air in your home, which can lead to a lower electric bill. If the heated or cool air leaks out, your system turns on more often. There are various types of insulation that you can install in your home and a home energy auditor can point out the best places for it in your house.


Mitsubishi Electric is a world leader in air conditioning systems for residential, commercial and industrial use. Challenged to create air conditioning systems that provide exemplary performance in the wide-ranging climatic conditions found throughout Japan, our engineers develop amazingly sophisticated yet durable units and systems capable of constant use under virtually any natural climatic condition on earth.
Filtration systems -- A second-stage filter is sometimes inserted & used to remove particulates such as pets, smoking or cooking, as well as other odors, gases, and VOCs (volatile organic compounds). A HEPA filter is also available to remove spores, pollens, bacteria and lung-damaging particles. There are also systems that use ultraviolet (UV) light to protect against bacteria and germs.
Concrete Blocks -- Concrete blocks are used in foundations and are often found in full basements. Insulating the spaces in the blocks is not the way to insulate them as the heat energy will travel along the concrete itself. The best way to insulate with concrete blocks is to use insulated concrete blocks, which have polystyrene incorporated into them.
Mitsubishi Electric is a world leader in air conditioning systems for residential, commercial and industrial use. Challenged to create air conditioning systems that provide exemplary performance in the wide-ranging climatic conditions found throughout Japan, our engineers develop amazingly sophisticated yet durable units and systems capable of constant use under virtually any natural climatic condition on earth.

Before opening the electrical cover on the A/C unit, be sure to shut off all power to the compressor unit and the indoor furnace or air handler, and verify that it is off. Note that this may mean shutting off a circuit breaker that serves the furnace and air handler, and then, near the compressor, pulling out the disconnect block (or shutting off the 220-volt power) to the outdoor compressor.

×