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Be Cool in Maine

Be Cool in Maine

Article written by Jack Carr, P.E., R.S., LEED AP, Criterium Engineers
Published in Condo Media, February, 2015


Up until recently out of state condo buyers were surprised to find most Maine condos were not centrally air conditioned.  Whereas in other parts of the country air conditioning is a given, Maine has had a tradition of building non-air conditioned condos either in it trust in its cool mountain and sea breezes or just plain Yankee thriftiness.  That of course is changing with the new condominium developments going up.  But what about the established condo unit inventory built over the last thirty years and how will they fare in today’s competitive real estate market?

To keep current in the market and meet the needs of retiring boomers who expect a climate controlled indoor environment in their retirement years, retrofitting condo units with central air conditioning seems like a good idea.  The problem is this type of conversion for a condo building with its design and bylaw restrictions can make it difficult to install a central system.  Space limitation and ductwork runs can make such a conversion not only cost prohibitive but almost physically impossible.  So what is the answer?  Perhaps one word, ductless.

Ductless, mini-split heating and cooling systems (affectionately known as a ‘mini-split’) were introduce over thirty years ago from Japan but only have recently caught on in this country.  They are widely used in Europe where efficiency and fuel costs are a major concern.  Similar to more familiar air-source heat pumps, mini-splits comprise two main components, namely, an exterior compressor/ condenser unit and interior air-handling unit.  These units are connected by a conduit containing the refrigerant tubing; suction tubing; condensate drain line; and power cord.

The new mini-splits chief advantage is there diminutive size and their ability to heat and cool individual rooms or a network of up to four rooms allowing flexible zoning.  Thermostats can be placed in each occupied zone needing conditioned air saving both money and energy.  As these systems are ductless, they avoid energy losses associated with long duct runs typically found in central air conditioning systems.  Duct energy loss alone can account for up to 30% of energy consumption especially when the ducts are located in a condo’s crawlspace or attic.  Keep in mind a mini-split system uses electricity to move heat from the outside to the inside or the reverse.  It does not use electricity to create heated or cool air, resulting in heat pumps producing four times as much energy as they consume.

In retrofitting an exiting condo unit a mini-split can be easier to install than virtually any other central air condition or heating system.  The connecting conduit to hook-up the interior unit to the exterior unit only requires a three inch diameter hole.  This conduit run can be as long a 50 feet allowing the interior unit to be in the front of the unit with the exterior unit being out of sight at the rear of the building or on the roof.

The slightly higher costs of retro-fitting a mini-split compared to a more traditional central air conditioning system is usually offset by the much lower operating costs and available rebates and financial incentives available not to mention the increase in market value of an air condition condo unit.  A mini-split equipment package cost ranges from $1,000 for a small single zone system to $3,000 for a 3-zone system.

Heat pump systems have always been questionable in a northern state like Maine.  As the temperature drops below 30 degrees these units start losing their heating efficiency, just when you need it most.  That is changing.  The new mini-splits are now suitable throughout Maine with some model being able to run at full capacity down to 5 degrees outdoors.  A new ‘low ambient heating’ technology sometimes called ‘hyper-heating’ creates an efficient heating/ cooling system while eliminating the need for a supplemental heating source as has been required with past heat pump systems.

And keep in mind; these are not the bulky window air conditioners of the past.  Many manufacturers such as Mitsubishi, Lennox, Trane, and Fujitsu have come out with very stylish units.   The new sleek designs fit most interior decors.  They can be recessed into the ceiling; mounted near the floor; or hung on the wall with decorative panels.  For the art lovers LG has come out with their ‘Art Cool’ line which is an air handling unit hung on a wall with an art frame in which you can mount your favorite artist’s work.

So even though it may be frosty outside now, planning to combat the dog days of summer with a full or partial air conditioning system in your unit may be as easy as a one word answer, ‘ductless’.