Install Instructions

IM-PR 566442 1114 (Design Manual)
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(furnaces, water heaters, dryers, etc.) contained
within the conditioned space or, if so, they are
to be of the direct-vent variety. The house does
not have powerful range hoods (i.e., 150 CFM
or greater). (A high-power hood that has its own
source of makeup air is acceptable.)Fireplaces,
if any, receive combustion air from the outdoors
and have tight glass doors.
Semi-Tight: Envelope conditions are
approximately between Tight and Average
Average: All structural panels, corners,
cracks, joints and penetrations reasonably
sealed by adequate workmanship using some
combination of air barrier (film), taping, packing
and caulking. Window and door assemblies
rated between 0.25 and 0.50 CRM per running
foot of crack at 25 mph (wind speed). All bath
exhaust fans, kitchen exhaust fans and dryer
vents are equipped with backdraft dampers.
The home does not use ceiling and recessed
light fixtures or, if so, there is a minor amount
of leakage around the fixture. No envelope
openings (per National Fuel Gas Code) are
required for combustion air. The house does
not have powerful range hoods (i.e., 150 CFM
or greater). (A high-power hood that has its
own source of makeup air is acceptable.)
Fireplaces, if any, receive combustion air from
the indoors but have tight glass doors and a
chimney damper.
Semi-Loose: Envelope conditions are
approximately between Average and Loose
Loose: There has been no effort or inadequate
effort (regarding methods, materials and
workmanship) to seal the structural panels,
the associated corner, cracks, joints and
penetrations and/or there is a large amount
of ceiling recessed light fixture (or light-can)
leakage. Window and door assemblies are not
rated, or are rated at more than 0.50 CRM per
running foot of crack at 25 mph (wind speed).
Some, or all, of the bath exhaust fans, kitchen
exhaust fans and dryer vents are not equipped
with back draft dampers. Envelope openings
(per National Fuel Gas Code) are required for
combustion air. Powerful range hoods (i.e., 150
CFM or greater) used that do not have their
own source of makeup air require powered
air-makeup, an open window for makeup air
or a negative pressure relief. Fireplaces, if any,
receive combustion air from the indoors and do
not have glass doors or chimney dampers.
Mean Cooling Water Temperature: Average
of supply and return water temperatures at the
radiant panel.
Mean Radiant Temperature: The effective,
overall temperature of those surfaces to or from
which a radiant panel may emit or receive heat in
the form of radiation. This temperature also takes
into account the inclination of the surfaces with
respect to the radiant panel, through a term called
the “angle factor.” For typical indoor applications,
the indoor ambient drybulb temperature can be
used as a proxy for the mean radiant temperature.
When there are large deviations in emissivity
and temperature across the surfaces seen by a
radiant panel, calculation of the MRT by a more
specific method may be required. (See ASHRAE
Fundamentals 2009, Chapter 9, for
more information.)
Outdoor Reset Control: A control method that
increases the water temperature in a hydronic
system as the outdoor temperature drops.
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Panel Piping: Piping that is used within the
radiant emitter.
Parallel Piping: Piping that has two or more
branches tied into a common supply and
common return.
Primary Piping: Piping that carries fluid from the
heating or cooling source to secondary piping,
panel piping or a radiant emitter.
Radiant Panel: PEX tubing consisting of a dry or
wet mass flooring system using any number of
attachment methods.
Reverse Return: Parallel piping in which the
first branch connected on the supply is also
the last branch connected on the return. This can
aid in providing balanced flow throughout each
parallel branch.
R-Value of a Material: A value indicating the
thermal resistance of the material. The greater the
R-value, the slower heat will conduct through the
material, all other conditions being equal.
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