Hydronic-Side Heat Exchangers; Temperature Limitations; Tv Unit Location / Mounting; Ground Source Design - Econar GeoSource 2000 GW Series Installation And Operating Instructions Manual

ground water
systems because
the loop
Entering Water
Temperature
(EWI)
is
lower. EWT
affects the capacity
of
the
unit in
the heating mode, and loops
in cold
climates
are normally sized
to
supply
a
wintertime
EWT to
the
heat
pump down to
25oF.
2.
Ground Water
Systems
(see
Figure
3)
The design water
tefirperature
will
be
the well
water
temperature
in
the
geographic
region
for gtound
water
systems.
Typical well
water temperatures
are
in
the
507
range
in
many cold climates.
If
well
water temperature is
lower
than
50T
(Canadian well
water
can
be
as
low
as
40oF),
the
flow
rate must be
increased
to
avoid
leaving
water temperatures
below
the freezing
point.
If
well
water
temperatures
are above
50oF
(Some southem
states are
above 70oF), the
flow
rates may need to be increased to
dump energy more efficiently during
the
cooling
mode.
Varying well
water temperatures
will
have
little
effect on
unit
capacity
in
the cooling mode (since
the well
is
connected
to
the heat
pump
condenser),
but
can
have
large effects on capacity
in
the heating mode (since
the
well
is
connected
to
the
evaporator).
If
well
water
temperatures exceed 70oF, special considerations such
as
closed
loop
systems should be considered.
C.
Hydronic-Side Heat Exchangers
Hydronic-side heat exchangers discussed
in
section
VI
are
designed
to
operate
at a specific
fluid
supply tenperature.
This operating temperature
will
have
to be supplied to
the
selected space
conditioning heat
exchanger
by
the
hydronic heat pump. The
manufacturers
or
suppliers
of
the hydronic-side heat exchangers
publish
the capacity
of
their equipment
at different
operating
temperatures and
fluid flow
rates,
and these
capacities
and
operating
temperatures are
required
to
select
the
heat
pump to
be
used
in
the
system.
When selecting the
heat pump,
choose
a unit that
will
supply the
necessary
heating
or cooling
capacity at
the
minimum
and maximum hydronic loop
temperature
conditions, respectively. Example;
if
a fan
coil
system
requires 35000
Btuihr to
cool
a
space
with
45oF water
temperature
entering the water-to-air fan
coil,
a GW42x
GeoSource
2000
heat
pump
is
required
to
handle
the
cooling
load.
lf
an intermediate heat
exchanger
is
used between
the
storage
tanks as pictured
in
Figure 1,
expect
a
10oF
operating
temperature
difference
between the
two
tanks.
For
example,
if
the
direct-coupled storage
tank
is
at
110oF, expect the
maximum
operating temperature
of
the
indirect-coupled tank connected through an intermediate
heat exchanger
to be
100oF.
D. Temperature
Limitations
Be
aware
of
the
operating
range
of
the geothermal
system
when sizing
the
particular
heat
pump to avoid premature
equipment
failure.
Operating outside
of
these limitations
may cause severe damage
to
the equipment and may
void
warranQr.
VCAUTIONS;
-The
acceptable
hydronic
LWT is
70oF
to
115oF for
heating and 35oF
to
50oF
for
cooling. Hydronic EWT
should remain above
50oF
to avoid low-pressure lockouts.
-The
acceptable
Ground Loop EWT is
25oF
to
50oF
for
heating
and
50T to
100oF
for cooling.
-The
acceptable
Ground Water EWT
is
45T
minimum
in
heating and
100oF
maximum in
cooling.
TV. UNIT LOCATION
/
MOUNTING
@Important
- To
ensure easy
removal
and replacement
of
access
panels, leave
panels
secured
in place until
the
unit is
set
in place
and
leveled.
qlmportant
-
Locate
*re unit
in
an
indoor
area where
the ambient temperature
will
remain
above 45oF. Service
is
done
primarily from
the
front. Top
and rear
access is
desirable
and should be
provided when possible.
elmportant
-
A
field installed drain pan
is
required
under the entire
unit
where accidental water
discharge
could damage surrounding
floors,
walls
or
ceilings.
VCAUTION -
Do not
use
this unit during
construcrion.
Dust and debris
may quickly
contaminate electrical
and
mechanical components; resulting
in
damage.
VCAUTION
-
Before driving
screws
into the
cabinet,
check on the inside
of
the
unit
to ensure the screw
will
not
damage
electrical, water, or refrigeration lines.
e-Important
-
Units
must be mounted on
a
vibration-
absorbing
pad slightly larger than the
base
to
provide
isolation between the
unit
and the floor. Water
supply
pumps should not be hard plumbed directly to
the unit
with
copper
pipe; this
could transfer
vibration from
the
water pump
to
the
refrigeration circuit,
causing
a
resonating
sound.
Hard plumbing must be
isolated from
building
structures that could fransfer vibration from
the
unit through
the
piping
to
the
living
space.
eCAUTION
-
Always
use
plastic male fittings
into
plastic
female
or into
metal
female
fittings. Never
use
metal male
fittings
into plastic female
fittines. On
metal-
to-metal
fittings;
use
pipe
thread compound, do not
use
pipe
thread tape, hand
tighten flrst,
and then
only
tighten
an
additional
Vz
tum
with
a
tool
if
necessary. On plastic
fittings,
always use
2
to 3
wraps
of
pipe tlread
tape, do
not
use
pipe
thread
compound, hand tighten
frst,
and then
only tighten
an
additional
7z
turn with
a
tool
if
necessary.
Do not over-tighten, or
damage
may occur.
V.
GROUND SOURCE DESIGN
Since water
is the
source
of
energy
in
the winter and
the
energy
sink
in
the
summer,
a good water supply
is
possibly the
most
important
requirement
of
a geothermal
heat
pump
system
installation.
5