Resource Library

Problem Set 1.1 What are some characteristics that can vary between water heaters? What is the difference between a conventional water heater and a heat pump water heater? Problem Set 1.2 What mode is the most efficient for the production of hot water? If planning to be away from the residence for...

Problem Set 2.1 What is the source of heat used by the HPWH to heat up the water inside the insulated tank? What substance goes from liquid to gas, and back to liquid in order to transfer heat to the water in the storage tank? Problem Set 2.2 What characteristics of a households affect the amount of...

Which of the following can air source heat pumps be used for? Cooling a household in the summer. Heating a household in a southern US state in the winter. Heating a household in northern US states in the winter. All of the above.

Match the terms with the correct definition. Definition Key Term 1) Nominal heating output of heat pump at 47°F (Btu/hr) as tested. a. Design Heating Capacity 2) Heat pump’s heating output at the outdoor air winter design temperature (Btu/hr). b. Design Heating Load 3) Overall cooling efficiency...

1. Which of the following components are in both heat pumps and air conditioners? Compressor Indoor coil Expansion valve All of the above 2. Why do some heat pumps have auxiliary heat? Auxiliary heat is more efficient Heat pumps sometimes need assistance in very cold outdoor conditions or with a...

A homeowner would like to add cooling to two offices in their 3,000 SF home with natural gas boiler. What is the best option for a heat pump in this scenario? Replace an existing ducted furnace system with a ducted heat pump Install a heat pump as the primary heating system but keep the existing...

Explain three benefits of air source heat pumps compared to fossil fuel heating systems.

Which of the following should be assessed before installing a heat pump? Is the electrical panel sized to accommodate the heat pump? Is there space to locate the outdoor unit so it gets proper airflow? Does the difference between the gas and electric utility rates in the area favor heat pump...

Which of the following statements is not true when replacing a ducted furnace with a ducted heat pump? The ductwork should be assessed to ensure it is properly sized for the new equipment Air conditioning will not increase the risk of condensation on the ducts The existing ductwork should be...

Chris is considering replacing his natural gas boiler with a multi-zone ductless heat pump system. The boiler has an efficiency of 70% and the ductless mini-split has an HSPF of 11.5. Chris uses 1,000 therms per year and pays $0.66 per therm and $0.11 per kWh. How much would it cost to run each...

Which of the following statements is a correct statement of the “law of diminishing returns”? A. Every time you increase the thickness of the insulation, heat loss increases by a factor of two. B. As you reduce the insulation level, heat loss decreases at a 1:2 ratio. C. Every time you double your...

Consider Table 1 in the Objective 3.1 (i.e., “Example of the results summary table based on matrix [g] for several lighting products”) for example LCA results. Which product has the lowest hazardous waste to landfill? What aspect of the lighting products might be contributing to the landfill waste...

What is the difference between LCCA and LCA? Why is the distinction important for building science?