It’s been a Cool Rainy Spring but those Hot Humid Summer Days are just around the corner. A Central Heat Pump/Air Conditioning System Would Be Nice!! Something Quiet and Efficient because the Cost of Electricity is Rising. What’s Available and What’s Best for Your Home?
What you purchase depends on two important items. Your Budget and Your Home. You can spend anywhere from $3500 installed for a Single Head Very Quiet Ductless Air Conditioner that does just a portion of your home to $30,000+ installed for a Very Quiet Ducted Central Heat Pump (HP) / Air Conditioning (AC) Geothermal System that does your entire Home. There are many very good choices in between.
When considering a system, the House you live in helps to determine which system you should choose. If Your Home is a One Story (Ranch Style) Home with an unfinished basement, a standard Ducted Air to Air Heat Pump System w/electric backup needs to be considered. The Indoor unit (Air Handler) is located as close to the center of the basement as possible and the Main Supply and Return Ducting will hang 10” below the Basement Ceiling Joists – so – it is best to have at least a 8’ basement ceiling height. Floor registers in each room (usually 2-1/4” x 12”) are used to distribute the conditioned air into each room in the house. The outdoor unit needs to be located 12″ from the outside wall of the house and if possible, near the indoor unit and away from occupied bedrooms. The outdoor units today are very quiet but if it is located too near a bedroom, you will hear it at night. If your budget permits you can also include a few nice options like a Gas Backup in lieu of Electric Backup for reduced operational cost, Electronic or Media Filter, Wi-Fi Thermostat and a Humidifier.
If Your Home is a Two Story Home with an unfinished basement and a wide open attic, a standard Ducted Air to Air Heat Pump System w/electric backup (same as a one story) needs to be considered. The system is installed the same way as a one story; then, to condition the upstairs bedrooms a supply and return duct is run through a chase to the attic and from there round ceiling registers (usually 6” diameter) branch out to carry the conditioned air into each room on the second floor. The chase can be installed in a first and second floor closet if one is above the other – or – it can be installed in an offset in the wall. Every two story house is a little different. It may take a little creative thinking but usually one can find a way to build a chase that will not “stick out like a sore thumb”. If the budget permits you may want to install two thermostats (zoning) since there is an inherent difference in temperature between the upstairs and downstairs, Gas Backup in lieu of Electric Backup for reduced operational cost, Electronic or Media Filter, Wi-Fi Thermostat(s) and a Humidifier. Because the attic is an unconditioned space, it is very important that you cover the ducting in the attic with additional insulation. The flexible ducting that is usually used in the attic has an R8.4 rating. I would suggest that you rent a machine that blows cellulose or fiber glass insulation and cover the ducting with another 12” of insulation which will bring the total insulation value to about R45.
Talk to your trusted HVAC Professional (call us if you like). He will schedule a site visit to “look over” the job, to discuss details of the installation with you and to provide you with a quotation.
We’ll continue this discussion for other types of homes in the next issue.
Curt Bierly is president of the bierly group incorporated of which Stanley C. Bierly is a division. He graduated from Penn State with a BS in Mechanical Engineering and is the chair for the Penn College HVAC Advisory Board. You can contact him at cbierly@bierlygroup.com or call him at 814-349-3000.