Showing results 1 - 100 of 104
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A battery storage system can provide reliable back-up power during a grid power outage
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A boiler system can be set up with primary and secondary loops to supply hot water for multiple uses
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A Category I induced draft boiler uses an induced draft fan to pull air through the combustion chamber and to the flue
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A ground source heat pump with an open-loop piping system using vertical injection and recharge
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A ground-source heat pump has the same components as a standard air-to-air heat pump except that the liquid-to-refrigerant heat exchanger coil is located inside rather than outside
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A ground-source heat pump with a closed-loop horizontal “Slinky™ “piping arrangement
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A high-efficiency gas boiler provides hot water to the faucets, to radiant heating loops in the basement floor, and to a hydro-coil for a central air heating system.
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A high-efficiency heat pump is installed in a closet within this home’s conditioned space.
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A mini-split air-conditioning system can be a highly effective low-energy approach to provide cooling to one designated zone in the house
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A single ductless heat pump heats and cools the country’s first DOE Zero Energy Ready certified manufactured home.
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After setting precast concrete basement walls on an 8-inch bed of trap rock, this builder sprayed 2 inches of closed-cell spray foam directly onto the ground then laid piping for radiant floor heating before pouring the concrete floor slab.
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An ultra-efficient layer of R-20 rigid foam foundation insulation covers the ground underneath the vapor barrier and radiant floor loops, which will circulate water heated by an ultra-efficient geo heat pump.
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By plotting the heating capacities at -4°F and 5°F and drawing a line between them, the capacity at 0°F can be estimated
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Category III oil-fired, sealed-combustion boiler configured as a direct-vented appliance that draws its combustion air from outside
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Category III oil-fired, sealed-combustion boiler with the burner assembly cover removed
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Cold-climate heat pumps can provide heating and cooling even in climate zone 7; this home retained a fuel oil boiler system for backup on the coldest days.
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Conduction is heat transferred by contact, like the hot pan that fries an egg or the hot asphalt that burns bare feet.
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Convection is heat transferred via air or liquid movement in a pattern of cooling/falling and warming/rising like hot water that rises and falls in a percolating coffee pot.
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Ductless indoor units like this one are controlled individually by handheld remote controllers.
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Heated air flow is produced when the heating cycle is energized (set thermostat to “heat”)
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Hot water for the home’s radiant floor heating system comes from roof-mounted solar thermal panels and an air-to-water heat pump provide.
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In a Category I gas-fired, natural-draft boiler, the natural draft of the heated flue pulls combustion air through the draft hood into the combustion chamber
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In heating mode, split system heat pumps absorb heat from the outside air and “pump” that heat to the indoor air handler unit, which releases it to the inside air.
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Passive cooling techniques can reduce or eliminate the use of air conditioning and can be used for backup cooling during emergencies.
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PEX piping is laid over 2 inches of XPS before the slab is poured to create a radiant floor heating system in this extensive home remodel.
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PEX piping loops are laid before the slab is poured for this radiant floor heating system
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Radiation is heat transferred through space by rays, like rays of sun that warm your skin if the rays are not blocked by a building or tree.
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Right - An energy recovery ventilation (ERV) brings fresh air into the home while exhausting stale air. Both ducts pass through a heat exchanger where heat from the warmer duct is transferred to the cooler duct.
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Right - The air handler for this geothermal heat pump is located in conditioned space.
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Right - The geothermal heat pump provides hot water for radiant floor heating, domestic hot water, and the air handler for space conditioning upstairs.
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Right - The high-efficiency wood stove is located on an interior wall in this home to provide a secondary heating source in cold climates.
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Right - The home’s ground source heat pump preheats water for the air source heat pump water heater.
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Right - The home’s high-efficiency gas boiler provides domestic hot water as well as in-floor radiant heat, while a high-efficiency heat pump provides cooling and a secondary source of heating.
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Right - the vapor barrier is extended up the sides of the piers in this crawlspace, which is sealed and insulated to house the HVAC ducts.
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Right - This ductless minisplit uses a ceiling-mounted rather than wall-mounted air handler.
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Right - This heat pump is located in a closet inside the home and all ducts are located within conditioned space between floors.
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Right – A mat is installed to contain radiant floor loops which distribute hot water from this home’s combi boiler.
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Right – Adequate space is provided near the air handler for the water lines of this ground-source heat pump.
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Right – An air-to-water heat pump efficiently provides hot water for radiant floor heating.
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Right – An air-to-water heat pump provides water and space heating while a heat recovery ventilator provides fresh air that is filtered by the HEPA filter.
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Right – The double compressor unit supplies multiple interior minisplit heat pump heads.
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Right – The ductless minisplit in this open area is installed in the ceiling rather than on a wall.
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Right (decent): For a relatively high-capacity ccASHP sized per Approach 3 or 4 to meet nearly 100% of the heating load, this heat pump’s modulating zone has a decent overlap with the home’s heating load line, reducing short-cycling.
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Right: Sized per Approach 1, this heat pump will have minimal short-cycling; since sized using Approach 1, it will require backup heat when temp is below 30°F but could still contribute significant heating down to heating design temp (-6°F) and lower
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Right: Sized per Approach 3 or 4, this heat pump’s modulating zone has a large overlap with the home’s heating load line, resulting in minimal short-cycling; the unit may require a small amount of backup heat during the very coldest hours of winter.
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Right: Sized per Approach 3, this heat pump’s modulating zone has a large overlap with the home’s heating load line; it will require backup heating but could still contribute significant heating for all hours of the heating season
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Shade trees planted on the east or west sides of a house are one of the most effective measures that can be taken to reduce heat gains
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Sources of heat gain in a house include solar gains, infiltration, conduction through walls and roof, occupants, and internal equipment
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Sources of heat gain in a house include solar gains, infiltration, conduction through walls and roof, occupants, and internal equipment
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The ductless air handler of a ductless heat pump can be mounted above the ceiling so that only the register is visible
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The high-efficiency air-to-air heat pump is set in an overflow pan with an emergency shut off sensor in case the condensate tube were to clog and cause condensate to fill up the pan.
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The high-efficiency mini-split heat pump provides cooling and heating; a drain pipe carries condensate away to a location that meets local code requirements.
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The NEEP Cold Climate Air Source Heat Pump List allows users to search, sort, and filter for cold climate heat pumps by brand, model, product type, and ducting configuration; an advanced search provides helpful resources for sizing to the heating load
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The ultra-efficient air-to-water heat pump draws heat from the outside air to heat inside room air in winter and domestic hot water year-round.
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These ducts were installed within the home's conditioned space in a central chaise down the main hallway.
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These plots compare sizing approaches in terms of the approximate annual heating load a heat pump might carry throughout the year for a hypothetical home in Minneapolis, MN.
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This “high static ducted cassette” heat pump system is similar to a traditional centrally ducted system, serving several areas of a home from one indoor unit
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This cold-climate heat pump can meet >90% of this home’s heating needs, even in Cordova, Alaska.
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This cold-climate heat pump provides heat at 77% capacity at 5°F, and 57% of capacity at -5 °F.
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This cold-climate heat pump provides heating and cooling for a home in Cordova, Alaska.
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This home is heated with in-floor hydronic radiant heating tubes that were installed on top of the R-20 rigid foam under-slab insulation.
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This home’s ultra-efficient ground-source heat pump provides hot water for space heating as well as domestic hot water for the 50-gallon storage tank.
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This Houston home’s unique tri-generation system combines cooling, heating, dehumidifying, hot water, and power production and storage.
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This multi-split heat pump system incorporates several indoor units connected to just one outdoor unit; the indoor units include a wall-mounted unit, floor-mounted, ceiling cassette, and mini-air handler.
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This plot shows a heat pump’s minimum and maximum cooling capacities overlaid with a home’s cooling load line, allowing a designer to assess how well-suited the equipment is for the specific home.
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This plot shows a heat pump’s minimum and maximum heating capacities overlaid with a home’s heating load line as well as the annual heating load hours for the home, allowing a designer to assess how well-suited the equipment is for the specific home.
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This plot shows a heat pump’s minimum and maximum heating capacities overlaid with a home’s heating load line, allowing a designer to assess how well-suited the equipment is for the specific home.
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This plot shows a heat pump’s minimum and maximum heating capacities overlaid with a home’s heating load line, allowing a designer to assess how well-suited the equipment is for the specific home.
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This single-zone mini-split ductless heat pump has only one indoor wall-mounted unit and one outdoor unit.
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This traditional centrally ducted heat pump heats and cools the entire home through a network of ducts.
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This upflow air handler for a traditional heat pump has an electric resistance auxiliary heating element located at the top of the unit (circled in red).
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Three-zone ductless mini-split system consisting of two wall-mounted and one ceiling-mounted indoor ductless units and one outdoor unit
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Three-zone mini-split system consisting of one wall-mounted ductless unit, one ceiling-mounted ductless unit, and one ducted indoor unit, all connected to one outdoor unit
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Typical coaxial coil (liquid-to-refrigerant heat exchanger) used in a ground-source heat pump
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Wrong – This ductless mini-split heat pump was installed above an exterior door allowing conditioned air to escape when the door is opened, heat transfer through the door, and temperature fluctuations that could impact the unit’s thermostat.