Ductless Mini Split Systems

John Owens Services has been active in the installation and servicing of ductless mini split systems in Marin County for over 20 years. Our most popular brand of ductless mini split is Fujitsu. We also represent Samsung, Trane, Mitsubishi, and Daikin.

What is a Ductless System

Of course, it has no ducts. There are no ducts to gather dust and dirt. There are no ducts to leak expensive heating or cooling energy into your crawl space or attic. Ductless or Minisplit systems are versions of Heat Pumps. A Heat Pump is an appliance that uses the refrigerant process to heat or cool a conditioned space (very similar to the technology in your refrigerator).

A simple ductless system comprises of one indoor wall unit connected by small refrigerant piping to one simple outdoor compressor unit.

Where would you install ductless systems? and why?

A ductless system can be used to heat and cool one room only. Or it can serve multiple areas of a home. One outdoor compressor can be connected to up to eight indoor units. Each indoor unit is self-contained and individually controlled. Ductless mini splits can be a problem-solving cooling system for a home office, a retrofit to a complete older home that has no space for ductwork. A good example of an older home retrofit is an Eichler home with a concrete slab and no attic. Eichler’s are prime candidates for multiple ductless units. In new construction the application could be a green energy efficient multi zone system for a new home. Mini splits are predominantly installed because of their flexibility for zoning, easy installation, and their high energy efficiency.

How are they so energy efficient ?

Heat pumps use electricity to pump refrigerant around a system. The energy used is running the pump or compressor. There are no heating elements. Heat Pumps extract heat from the outside air ( heating ) or extract heat from the inside air ( cooling ). Heat pumps can be up to 450 percent efficient. That means 1 kilowatt in and up to 4.5 kilowatts out. This high efficiency of the refrigerant process makes it very economic for the consumer to use electricity to heat and cool.

Variable speed compressors are the heart of ductless systems. The speed of the compressor varies according to how much work the heat pump has to do. This further improves electrical efficiency (up to 40% less electrical energy used than a conventional single speed compressor)

Multi zone technology further improves efficiency. One only needs to heat or cool the rooms you are using, and different rooms could be on different schedules.

Are there many different types of indoor units?

That’s a good question. Yes, there are many variations of the indoor units, and each company has a slightly different design to their units.
















Why have I never heard of ductless systems before?

The Japanese were the pioneers of this technology. Ductless has be popular around the world for decades especially in places where energy costs are high or in a culture that did not have a history of traditional furnaces and ductwork as we do in the United States.

If you’ve travelled in Europe, Asia, or South America you have probably seen these ductless systems in your accommodations.

Installing and Servicing Ductless Systems in Marin County

Air Conditioning Technicians need to be highly trained and certified to handle refrigerant gases.  Air conditioning equipment contains refrigerants. Ductless units run at extremely high pressures that can potentially be dangerous. Refrigerant gases have long been known to effect and damage the Ozone layer.  Refrigerants are controlled by the Clean Air Act. The main purpose of the Clean Air Act is to set forth proper procedures for dealing with refrigerant gases.  The procedures effect the storage, transfer, removal and recycling of potential Ozone depleting gases.

John Owens has been EPA refrigerant gas certified since 1994, and has maintained an impeccable no violation record with the EPA for over twenty years. Safety and training is the key to maintaining good refrigerant gas management.

The State of California maintains energy standards for heating and cooling equipment. Installations are now required to have independent third party testers who verify that our installations meet mandatory standards (a Hers Rater or tester – is a person who is a Home Energy System Verifier ). Hers testing is required by all Cities in Marin County.

One test is required for ductless mini split systems – Refrigerant Charge Verification –  refrigerant charge is critical in air conditioning. If the charge is incorrect running costs can be 30 % higher

The correct sizing of a ductless system is critical. The old rule of thumb methods for sizing heating and air conditioning do not work. From years in business we always have a good idea of what size unit will be required. However, the only accurate method is to perform a heat loss, heat cool analysis of the entire building to calculate the exact heating and cooling requirements of a system before the final selection of the equipment can be made (also known as Manual J calculations). We use software that performs these calculations to verify the size of the systems needed.

Ductless system installations are very regulated for ultimate energy savings and your piece of mind. Our Air Conditioning Technicians are EPA certified and Air Conditioning installation and repair certified.

We offer a five years parts and labor in house warranty on all heating and cooling equipment we install. This is in parallel with the Manufacturers warranty which often does not cover labor. Call us today for an estimate for a new ductless system installation or call to schedule an annual preventive maintenance checkup of your existing ductless mini split.



Fields marked with an * are required
Read Our Online Reviews

Located in Marin County, John Owens Services, Inc. has 30 years experience in licensed repair and replacement of boilers, radiant heating, HVAC, electrical, furnaces, plumbing, and is an authorized service provider of Rinnai products.