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Question
What is the ideal approach temperature difference in a brazed-plate heat exchanger?
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Answer
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Related questions
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What is the simple payback of a renewable energy heating system? a.
the installation cost divided by the annual operating cost savings b.
the number of years required for the investment to repay the higher initial cost using the savings it generates, relative to that of a conventional system c.
the number of years required for the annual operating cost savings to equal the installation cost d.
the installation cost divided by the difference between the installation cost of the system and a conventional system
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How is after-tax lost opportunity cost calculated? a.
total interest income earned multiplied by percentage of income retained by the owner b.
total interest income earned multiplied by income tax percentage c.
installation cost divided by annual operating cost savings d.
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What do straight lines on a simple payback curve imply? a.
The inflation of fuel cost was included. b.
The inflation of fuel cost was not included. c.
The fuel cost was not considered in the calculation. d.
The installation cost was not considered in the calculation.
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What is the function of a variable-speed setpoint circulator? a.
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Besides HDPE, which material is commonly used in earth loop heat exchanger piping? a.
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minimum fluid temperature b.
serial or parallel piping layout c.
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about equal to the average low summer air temperature c.
about equal to the average high winter air temperature d.
about 65 degrees F in most areas of North America
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the ratio of heating load to total heating and cooling load b.
the percentage of total load it can meet c.
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For a heat pump system with diurnal heat storage, when is the most favorable time for the heat pump to operate during winter? a.
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Its components last longer because they must be made of non-corroding materials. b.
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Maximum head loss is generally independent of flow rate. a.
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Q:
Which code requirements may vary between locations? a.
use of double-wall heat exchangers and collector array grounding b.
percent of total heat load that may be supplied by solar energy c.
requirement for grounding and pressure-relief valves d.
none, because of the requirement of uniform code requirements
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What would result from increasing the pressure rating of the relief valve? a.
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intermittent load; heating starts at low temperatures b.
year-round load; heating starts at low temperatures c.
intermittent load; heating starts at high temperatures d.
year-round load; heating starts at high temperatures
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2-pipe buffer tank configuration b.
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piping arrangement and inlet water temperature c.
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Repurposed propane tanks can be used in both open and closed hydronic systems. a.
True b.
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What is used to calculate net collector area for an evacuated tube solar collector? a.
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dimensions of exposed glazing c.
dimensions of the absorber plate and headers d.
dimensions of the mounting surface minus the dimensions of the absorber plate
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