Friedrich kuhl r-410a ユーザーズマニュアル

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Following is an example using the heat load form:
A space to be conditioned is part of a house geographically 
located in an area where the lowest outdoor ambient winter 
temperature is 40°F.  The calculated heat loss is 184 BTU/
Hr./°F.
Subtract 40°F (lowest outdoor ambient temperature for the 
geographical location) from 70°F (inside design temperature 
of the unit) for a difference of 30°F. Multiply 184 by 30 for a 
5500 BTU/Hr. total heat loss for the calculated space.
On the graph, plot the base point (70°) and a point on the 
40°F line where it intersects with the 5500 BTU/Hr. line on 
the left scale.  Draw a straight line from the base  point 70 
through the point plotted at 40°F.  This is the total heat loss 
line.
Knowing  that  we  have  a  5500  BTU/Hr.  heat  loss,  and 
we expect that our heat pump will maintain a 70°F inside 
temperature at 40°F outdoor ambient, we plot the selected 
unit capacity BTU/Hr. of the unit between 35° and 60° on the 
graph and draw a straight line between these points. Where 
the total heat loss line and the unit capacity line intersect, 
read down to the outdoor ambient temperature scale and 
fi nd that this unit will deliver the required BTU/Hr. capacity 
to approximately 30°F.
The heat load form on the following page may be used by 
servicing personnel to determine the heat loss of a conditioned 
space and the ambient winter design temperatures in which 
the unit will heat the calculated space.
The upper half of the form is for computing the heat loss of 
the space to be conditioned.  It is necessary only to insert 
the proper measurements on the lines provided and multiply 
by the given factors, then add this result for the total heat 
loss in BTU/Hr./°F.
The BTU/Hr. per °F temperature difference is the 70°F 
inside winter designed temperature minus the lowest outdoor 
ambient winter temperature of the area where the unit is 
installed.  This temperature difference is used as the multiplier 
when calculating the heat loss.
The graph shows the following:
Left Hand Scale 
Unit capacity BTU/Hr. or heat loss 
BTU/Hr.
Bottom Scale 
Outdoor ambient temperature, base 
point.
Heat Pump Model 
BTU/Hr.  capacity  heat  pump  will 
deliver at outdoor temperatures.
Balance Point 
Maximum BTU/ Hr. heat pump 
will deliver at indicated ambient 
temperature.
HEAT LOAD FORM