Lennox is the leader in advanced, energy-efficient HVAC systems that provide reliable comfort for light commercial buildings. From retail stores to restaurants, schools to healthcare facilities, Lennox HVAC systems are designed to improve comfort, reduce total cost of ownership, protect indoor air quality and simplify installation and maintenance. Choose from a wide range of innovative systems including Lennox VRF, Packaged Rooftop Units, Solar-Ready Systems, Commercial Controls, Split Systems, Mini-Split Systems, Heating Systems, Indoor Air Quality Systems and Energy Star® Products. Find Comfortmaker® products sold and installed in Portland, OR ? Daikin provides innovative, premium, energy-efficient indoor climate management solutions to meet the changing needs of commercial and industrial customers. Only select technicians in the business can call themselves Daikin Comfort Professionals. Each one is thoroughly vetted before being approved to offer and install Daikin indoor heating and cooling system equipment.

We do this to ensure that your satisfaction is consistently met. Find one in your area.Mini-splits and standard air conditioners both rely on simple thermostats. Heating and cooling account for around half of all energy used in the average home, according to the U.S. Department of Energy, so your choice of an air conditioning system can have an impact on both utility bills and the environment. While standard air conditioning systems remain more common in U.S. homes, mini-split systems could be a better buy for some homeowners. When comparing these technologies, consider equipment costs and operating costs to find the best system for your home. Understanding Cooling Systems Most people are familiar with standard air conditioners, which use a central outdoor compressor and direct cool air through a network of ducts to distribute it throughout the home. Mini-split air conditioners represent a newer technology. They include an outdoor compressor/condenser as well as an indoor fan unit. The indoor unit mounts to the wall or ceiling within a single room and connects to the outdoor unit via a small conduit.

These systems do not use ducts, but instead transport refrigerant through the conduit to cool a single room or other small area. small wall mounted air conditioning unitsYou can connect multiple indoor fans to one outdoor unit to cool multiple rooms, or cool just one room using a single fan. window ac units for small windowsThese systems typically are not designed to cool the entire house like a central air conditioner. thru wall ac heat unitsUpfront Cost for Mini-Splits The U.S. Department of Energy estimates that mini-split air conditioners cost about 30 percent more than central systems based on cooling capacity. A single 1-ton mini-split averages $1,500 to $2,000, according to an August 2012 report by the DOE. A similar technology, mini-split heat pumps, which can heat in the winter and cool in the summer, cost $3,000 to $5,000 on average, according to an October 2013 report by Building Green.

Upfront Cost for Central Air If you already have forced air heating via a network of ducts, plan to spend $3,500 to $4,000 for a central air conditioner capable of cooling a 2,000-square-foot house, based on a 2014 estimate by This Old House. If you don't have existing ducts, plan to spend about double that amount for your new systems plus the required ductwork. Operating Costs Central air and mini-split cooling systems work very differently, which can result in significant differences in operating costs. Central air systems cool the entire house, including occupied and unoccupied rooms. Mini-splits can cool much more economically because they represent a type of zonal cooling, meaning they only cool occupied rooms. If you only need cooling in a small part of the house, mini-split systems may save you money on energy bills. These systems also save by eliminating duct losses, which account for about 30 percent of the energy consumed by a central cooling system, according to the DOE. Installation and Repair One cost that's easy to overlook as you compare cooling systems relates to the installation of repair associated with these systems.

If you don't have ductwork in your home, installing central air can be a messy and time-consuming process that requires tearing open walls and ceilings. This often leads to the need for wall repairs, painting and other refinishing that can add to total installation costs. Homeowners without existing ducts can reduce mess and installation time with mini-splits, which require only a 3-inch hole drilled in the exterior wall to accommodate the conduit. References U.S. Department of Energy: Heating and CoolingU.S. Department of Energy: Ductless Mini-Split Air ConditionersBuilding Green: Electric Heat Comes of Age -- Installing Our Mini-Split Heat PumpThis Old House: Adding Central AirU.S. Energy Information Administration: Air Conditioning in Nearly 100 Million U.S. Homes Photo Credits Jupiterimages/Creatas/Getty Images Suggest a CorrectionMy previous post was about our Mini-Split A/C unit, purchased to get us through the few weeks of >100F weather we had this summer in the Twin Cities.  But the post also alluded to the ability of these units to heat. 

Now that it’s cooling off, let’s take a look at that. What these units do is move heat.  Amazingly, they can move it in either direction!  In the summer, they move heat out of the house, obviously enough, just like any A/C.  But in the colder months, they can move heat into the house as well.  Even when it’s cold outisde, you ask?  How is that possible? Even when it’s freezing outside, there is still heat. Until we get to absolute zero, there is still heat present which can be moved around.  Let’s say you keep it at 0F.  How does it stay at 0F?  Well, if it ever gets to 1F or 2F, it extracts heat from the inside of the freezer, and moves it to the outside (i.e. your kitchen).  So yes – it’s moving heat from a very very “cold” place and warming up a warmer place as a result.  The mini split heat pump works this same way. My Fujitsu ASU12RLS2 / AOU12RLS2 indoor/outdoor units can actually extract heat from the outdoors even when it’s -5F, although the efficiency diminishes as the outdoor temperature drops. 

Air source heat pump efficiency is expressed by the HSPF (Heating Seasonal Performance Factor), which, via Wikipedia, “is a ratio of BTU heat output over the heating season to watt-hours of electricity used.”  HSPF is expressed in BTU/Watt-hour, and my unit has a rating of “12” meaning that for every Watt-hour of electrical energy it uses, it moves 12 BTUs into the house, on average, over the heating season.Ok that might not mean much.  But get this: Watt-hours (Wh) and BTUs are both expressions of energy, just expressed in different units.  There are 3.413 BTUs in a watt-hour of electricity.  So for every 3.413 BTUs of electrical energy we input, we get 12 BTUs of heat into the house, for a multiplier of about 3.5x.  How’s that for efficiency!  By comparison, a simple resistance space heater is 1:1, providing 1 unit of heat for every 1 unit of electrical energy input.  The difference is that a heat pump moves heat rather than creating it directly, and is therefore able to do so with more than 100% efficiency.

So it’s 350% efficient, that’s great and all, but natural gas is cheap, and electricity usually comes from coal – does it make sense from either an environmental or a cost point of view?  I created a spreadsheet on Google Docs to take a look.  An abridged version is here: With the following assumpti0ns (take a look at the spreadheet to alter them): 82 AFUE boiler, $0.71/therm natural gas, $0.10/kWh electricity, a 12 HSPF heat pump, and 1161 lbs CO2 per MWh, it looks about break-even on operating costs, but about a 30% reduction in CO2.  Of course things like energy costs and carbon intensity vary by region; for carbon intensity numbers for your grid region you can look here (I actually took numbers from my utility’s annual report). So that looks pretty good, and in fact if we may have even a bit better outcome, because: The one downside, right now, is that we have just one of these things, at the top of the stairs.  It’s a point source of conditioning so distribution is something of an issue.