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Ductless Heat Pumps For Commercial Applications. Gary Nordeen, Emperor Absolute Bill Kingrey, P.E. 11/5/08 AFE Webinar. What is a Heat Pump?. Heat Pump Components. Cold gas. OK, What’s a Ductless Heat Pump ?. Air Source heat pump Can be very efficient SEER 20 + HSPF 9 +
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Ductless Heat PumpsFor Commercial Applications Gary Nordeen, Emperor AbsoluteBill Kingrey, P.E.11/5/08 AFE Webinar
Heat Pump Components Cold gas
OK, What’s a Ductless Heat Pump? • Air Source heat pump • Can be very efficient SEER 20+ HSPF 9+ • Efficient at low outdoor temperatures • No ducts
Why are DHPs better than other technologies? • High efficiency • Zonal system • Ease of installation • Eliminates ductwork
You should consider DHPs for one of more of the following reasons: • Low-cost heating and cooling • Easy installation • Modular units can be installed nearly anywhere • Improve occupant comfort
Commercial vs. Residential Installations • Ventilation requirements (15-20 cfm/person) • Interactions with existing systems • Simultaneous heating and cooling • Three-phase available, single phase required • Control systems
Planning Questions • Is my application a good one? • Can I meet all required codes? • Will a DHP save me money or improve comfort? • Can the unit be installed where I want to install it?
What Are Some Good Applications? • Add cooling to a zone in an existing building • Computer room cooling or backup • Supplemental heating and cooling for an undersized zone • Provide heating & cooling in a small area to allow shutting down a large system
What About Codes? • Commercial buildings must be ventilated during occupied hours • Airside economizer requirements and exceptions • Simultaneous heating & cooling prohibited • Pressure testing of refrigerant lines
How Can a DHP Save Money? • Offset more expensive heating and/or cooling with higher efficiency equipment • Extend the life and reduce maintenance of existing equipment • Calculate fuel costs to be sure
Where NOT to Install DHP? • In areas served by central systems with existing problems. • Don’t try to use a DHP to “fix” an unsatisfactory system
Where NOT to Install DHP? • In hospital treatment areas • In areas with corrosives or dust in the air
Before You Buy • What size heat pump do I need? • Provide heating, cooling or both? • Determine the number of zones • Calculate heating and/or cooling loads • Match the product with your climate • Voltage requirements
Sizing Considerations • Determine the load • Supplemental heating or cooling • DHP for entire load • Where does ventilation air come from? • Does the DHP have to heat or cool outside air?
Choose an Indoor Unit Style • Wall mounted • Ceiling hung
Choose an Indoor Unit Style • In-Ceiling Unit • Concealed duct (ducted ductless)
Installing DHP • Plan the installation • Install outdoor unit • Power supply • Install indoor unit(s) • Connect refrigerant and power lines • Condensate drain • Commissioning unit
Installing the Outdoor Unit • Check clearance • Determine line set length and height restrictions • Provide secure mounting • Seal wall penetrations • Route piping and power to indoors
Locating the Outdoor Unit(s) Outdoor units may be placed on ground or attached to the building
Power Supply • 208v-240v from electrical panel to outdoor unit • Provide separate breaker for DHP • Interior units powered from outdoor unit • Provide electrical disconnect
Line Sets & Power Connections • 220 power from panel • Power out to indoor units • Refrigerant lines • 2 indoor units installed
Locating the Indoor Unit(s) • Noise considerations • Air circulation • Line set location • Condensate drain • Power
Locate the Indoor Unit • How will you get the condensate to a drain? • Can installation clearances be met? • If using a concealed duct unit • Check allowable duct lengths • Never install in unconditioned space
Removable filters for cleaning Electrical connection
Condensate Line • Route to storm drain or sanitary drain via gravity if possible • Or provide small condensate pump • Keep the drain line clear or the interior unit may leak condensate
Commissioning the Unit • Check refrigerant charge – or have it done by contractor with the proper equipment • Set and lock unit cooling and/or heating temperatures
Maintenance • Clean air filter(s) regularly • Check outdoor coils for blockage annually • Check the condensate drain and pan to make sure condensate can drain freely from the unit • If using wireless controls, change batteries as needed
More Information • Resource List at Northwest Building Efficiency Center www.nwBuildings.orgxxxxxxxxxxxxx • US Department of Energy www.eere.xxxxxxxxxxxxxxxxxxxxx • Manufacturers and HVAC Contractors