FAQs

This section will help answer some of the questions we are asked most often.

Q. How big is the new M-Series indoor unit?

A. Mr. Slim's indoor unit is compact and mounts discreetly high on the
wall where it is mostly out of view.

Q. How big is the new M-series outdoor unit?

A. Mr. Slim's outdoor unit is not bulky like the conventional style units you are used to seeing. The unit's very thin profile allows it to be mounted discreetly along the back or side of the home. Because the height is minimal, a small planting of shrubbery will also keep it from plain view for a more pleasing appeal. Please refer to table below for actual dimensions.

Q. How quiet is Mr. Slim?

A. Mr. Slim is designed to be quieter and more efficient than old window units, so you'll sleep easier with less worry about operating costs. The unit's fan is designed to deliver air quietly with only a gentle whoosh.  (That's why Mr. Slim is the first choice for thousands of churches, schools, and libraries.)

Q. How does Mr. Slim work?

A. Mr. Slim employs the same mechanical components as any basic air-conditioning system whose interactions cause the process of evaporation to occur. Mr. Slim is a split-ductless design, which simply means the indoor unit is separated from the outdoor unit and is connected by a gas and a liquid refrigerant line. The outdoor unit is considered the hot-side during the air-conditioning process. The cold-side unit is located indoors. In the heating process the compressor reverses this operation, and the heat energy is evaporated in the outdoor unit.  Then the indoor unit collects this heat energy while a fan blows air over the indoor coil and distributes the warm air into the room.

Q. What are the installation considerations for mounting the Mr. Slim M-Series indoor and outdoor units?

A. The indoor unit is typically installed high on an exterior wall. An exterior wall allows for easy connections between the indoor and outdoor units. The indoor unit is suspended on a wall bracket that is first mounted and secured to the wall. Because the indoor unit is so light, there is not significant pressure placed on the wall. The indoor unit is mounted horizontally and must be leveled. For the best circulation and air distribution the unit should be at least seven feet high or six inches below an eight-foot ceiling.

The outdoor unit should be mounted in a convenient location to allow for easy connection to the indoor unit. However, you can place the outdoor unit up to 49 feet away from the indoor unit if you wish. The outdoor unit can be placed close to the wall but must have at least a foot away. The outdoor unit should be mounted on a concrete pad to assure level footing. The fan outlet should be facing away from the home or the unit can be mounted perpendicular to the wall.

Q. What color is the M-Series indoor unit?

A. The units are white with varying degrees of brightness across the product line.

Q. Why do you need a three-inch opening in the wall to install Mr. Slim?

A. Unlike window units or hotel style units, which require a large wall or window opening to be cut, Mr. Slim only requires a three-inch round opening. This opening in the wall is necessary to allow the refrigerant lines and the wiring to connect the indoor unit to the outdoor unit. This opening is sealed and insulated by your installing contractor so no drafty air leaks or water from outside get in.

Q. What is the I FEEL mode on the M-Series remote controller?

A. This answer applies to all newer M-Series equipment. This function samples the indoor temperature for 2 minutes and then based on that temperature chooses the mode the unit will operate in. If the temperature in the room is more than 79 degrees it will be set in the Cool mode at 75 degrees. If the room temperature is 77 to 79 it will be set to the Cool mode minus 4 degrees of the current room temperature. If the temperature sensed is 73 to 77 degrees then the unit will be set in the Dry mode minus 4 degrees of the current room temperature. If the room temperature is less than 73 degrees then the unit will be set in the Heat mode. In the "I Feel" mode the temperature display disappears and pressing the "Too Warm" or "Too Cool" button will change the set point by 2-4 degrees.

Q. Why should I consider buying Mr. Slim?

Mitsubishi Electric is the industry leader in ductless air conditioning technology. Our innovations have defined cutting edge technology for years. Compare and you'll see no one surpasses Mr. Slim's performance for quiet, easy-to-use energy efficient operation. And since our ductless technology carries the Mitsubishi Electric name, you know every unit is built to last. The bottom line is that Mr. Slim delivers the ultimate control of comfort for your home or office. It's true today and will be comfortably self-evident for years to come.

Mr. Slim provides all of these important benefits:

  • Quiet and efficient operation: Mr. Slim runs at as little as 26 dB(A). This means that you can hold a quiet conversation or sleep without having to worry about the air conditioner interrupting you.
  • No ductwork is required: You will not have to tear up walls or add expensive ductwork to basement remodels
  • Will not take up a window:  If you take as much pride in your landscape as you do your home, you will appreciate that you can enjoy your handy work from the inside now that you have gotten your window view back. If you own a window unit then you are also concerned with the security issue of someone taking it out and coming inside your home. Mr. Slim eliminates this concern.
  • Effective zone cooling and heating: True zoning means that you can tailor individual rooms to your personal comfort tastes. Perhaps you prefer it cooler in the bedroom or kitchen. Also if do not use your guestrooms, dining room, or bonus room regularly, why cool them day-in, day-out?
  • Versatility: You can air condition spaces you at first thought impossible because there is no space for ductwork and you don't want a window unit. Both at the home or office, Mr. Slim is flexible enough to work in almost any room environment.
  • Remote controlled operation and timer functions: With Mr. Slim, you can control your comfort from across the room. The M-series comes with a wireless remote controller that gives you control of temperature, fan speed, vane operation and more. Plus a timer function means that you can set Mr. Slim to operate when you need it to. For example, if you know you arrive home from the office around 6:00 PM, you can set Mr. Slim to turn on at 5:00PM to begin cooling before you get there. This means that you are not cooling or heating your home while you're not there, which saves you money.

Q. PURY-100/80TMU related: What type of communications is used with the City Multi systems?

A. City Multi uses a 24 to 30 volts D.C. digital communication called Mitsubishi Network (M-net). This network voltage is generated from the outdoor unit to the B.C. controller and all the indoor units. This allows for constant communication between all components in the system that operate via the M-net.

Q. PURY-100/80TMU related: Do you require a special control wiring type for the M-Net?

Yes. It must be a #16 or #18 gauge, two conductor, stranded and shielded cable.

Q. PURY-100/80TMU related: Do you need to ground the shielded cable?

Yes. However it will only go to earth ground at the outdoor unit, no where else.

Q. PURY-100/80TMU related: What is the best way to wire in a safety circuit for a condensate pump?

For the PLFY, (ceiling mount), series there is a condensate pump already installed and the safety is factory wired. For the PDFY, (ducted model), and PKFY, (wall mount), *(with the exception of the PKFY-08NAMU-A)*, series there is a red jumper located on the circuit board at CN31. You simply cut the red jumper wire and attach your pump safety wires to the two new red wires just created. For the PKFY-08NAMU-A it is recommended that you break your main 115-volt feed to the indoor unit through the safety circuit for the pump. For CMB, (B.C. controller), series it is the same as above however it is a red jumper located at CN13 that must be cut.

Q. PURY-100/80TMU related: When using a Simple MA controller can I change the operation mode?

No, you can only turn the unit on and off, adjust the temperature, and change the fan speed.