Econar; Radiant Floor Heating; Fan Coils - Econar GeoSource Ultra GW Series Installation And Operating Instructions Manual

II.
HYDRONIC HEAT PUMP
APPLICATIONS
A. Radiant Floor Heating
Radiant
floor
heat tubing
is
probably the
most popular
form of
hydronic heating.
It
provides excellent comfort
and very
high
efficiencies
by
supplying
low
temperature
fluid
to
the
floor
slab and keeping the
heat concentrated
evenly near
the floor.
Radiant
floor
systems
heat
the
occupants and surfaces
directly with
comfortable
radiant
energy.
In
contrast,
forced air heating moves air
around
the
building, which
can
create temperature sfratification,
drafts, and air rising to
the
ceiling.
Remember that
hot air
rises, radiant energy
does
not.
Radiant
floor
heating usually
consists
of
l/2
inch plastic
tubing (PEX)
approximately one linear foot of pipe
per
square
foot of floor
space.
This value is
doubled
for
one
pass along the outside walls to
concentrate more
heat
in
that
area.
The tubing is generally laid into
the
concrete
slab
floor of
the building. New construction
techniques
have also made installation
into
wood floors
and
suspended
floors possible. The amount and spacing
of
the
tubing
is
sized
to
meet the heating
load of the
space
at
a
certain
fluid
temperature
in
the tubing.
To
optimize
efficiency and
capacity,
the
fluid
temperature
in
the
tubing
should
be
maintained
as
low
as
cornfortably
possible.
The type
of floor
covering and the spacing
of
the
pipe in
the floor
have
the
greatest effect
on
operating fluid
temperafure.
Table
1
gives
a
rough
estimate
of
expected
operating temperatures
for
specific
floor
coverings:
Table
1-
Floor
ECONAR
designs
its hydronic heat pumps using
a
115oF
leaving water temperatue
(LWT)
design
point. This
LWT
is
the ideal maximum
fluid
temperature
for
radiant
floor
systems.
Higher
operating temperatures
would
result in
an
uncomfortable hot feeling
in
the conditioned
space. In
fact, boilers
connected
to
radiant
floor
heating
systems
must be restricted
to a
115oF
maximum
temperature by
mixing
valves or other
conffol
devices.
Suppliers
of
radiant
floor
heat exchanger tubing can help
size the
length of pipe
and
fluid
temperature required
for
specific radiant
floor
heat exchanger applications. Be
sure
to include
two
inches of polystyrene
insulation under
the
slab and two to four inches around the perimeter down
to
a
four-foot
depth.
This insulation
reduces the heat loss
to
the ground
and
decreases
the
response
time
of
the
heating
system.
Insulation is
as
important
in
radiant floor
heating
as
it
is
in
other methods
of
heating.
Poorly
insulated buildings
can
result in higher floor
temperatures
needed to heat
the
building, which
could
exceed the
level of human comfort.
Night
setback
confols
are
not
recommended on radiant
floor
systems due
to
the slow
response
time of
the
slab,
and radiant
floor
systems
are not usually
recommended
for cooling,
since
poor dehumidification
and
cold/clammy
floors
may result.
To
provide cooling to
a radiant floor
heating installation, the installation
of
an
ECONAR
FC
fan coil unit is
recommended. Another
alternative
is
a
GeoSource
DuaITEK
combination
heat
pump.
B. Fan Coils
Fan
coils,
such as
the ECONAR FC
series, can
be
used
with ECONAR's hydronic
heat pumps
in
the heating
and
coolilg
mode.
In
many
cases,
radiant floor
heating
and
fan coil cooling
are used
together. Fan coils
also
provide
dehumidification
in
the cooliag
mode, and
the rate of
dehumidification can be
adjusted
by
selection
of
rhe fan
coil operating temperature.
Many different
sizes and configurations
of
fan coils
are
available, making them very
flexible to
each
particular
application. Valence heating
and
cooling
systems,
which
use
natural
convection
to
move
air,
can also be
very
versatile.
clmportant
-
Fan
coil
units
for
cooling
must have
a
condensate
pan; and
if
accidental water discharge could
cause
properfy
damage, there must
also
be
a
drained drain
pan under
the
unit.
Fan
coils
are sized
for
capacity at specific
water
flow
rate
and
temperature combinations. Sizing
also depends on
air
temperatures, air
flow
rates
(which
remain constant
based
on fan
speed selection and static pressure
differential),
and
humidity
conditions. The fan coils
are then matched
to
the heat
pump at a
common system
flow
rate
and
operating temperature
to
provide the overall
system
capacity to
a
space load.
High
static pressure
fan coils
have
recently come onto
the
market, which work well with
ECONAR's hydronic
heat
pumps. These
systems
provide
heating and cooling for
houses
without ductwork. They
use
a
high
static pressure
blower
to
supply
air
through small
tubes,
which
run
through
chaseways to the
living
space. The
blower
passes
air
though a water-to-ai.r coil
that
is
coupled
to
a
hydronic
heat
pump
to provide
heating and cooling.
These
systems
work
nicely on retrofit
applications where
ductwork isn't
available or wanted.
-1
Floor Coverinp
Temp
fF)
Caroetine
115
Tile/Linoleum/Hard Wood
100
Concrete/Ouarrv
Tile
-
Residential
85
Concrete/Ouarrv
Tile
- Commercial 70