Econar GeoSource Vara GV Series Installation And Operating Instructions Manual page 9

2.
Water Coil Maintenance
Water
quality
is
a
major
concern
for
open systems.
Problems
can
occur from scaling, particle buildup,
suspended
solids, corrosion,
pH
levels outside
theT-9
range,
orbiological
grorth. Ifpoor
water
quality
is
known to exist
in your
area,
a
cupro-nickel water coil rrny
be
required when ordering the
system,
or
installing
a
closed
loop
system
may
be the best
altemative. Water
coil cleaning on
an open
loop
system
may
be necessary
on
a
regular
basis.
Depending on the specific water
quality
issue, the water
coil
can be cleaned by the
following
methods:
a.
Freeze Cleaning
(Scale deposits, particle
buildup)
I.
Before using
the
freeze cleaning procedure, verify
that
it
needs
to
be
done. Answer
the
following questions to
determine
if
servicing is
required.
1.
Determine and
verify
that the required water
flow
rate
in GPM
is
both present and correct.
2.
Determine the temperature
differential of
the
water. Under normal conditions, there should
be a
temperature difference
ofabout
10-15 degrees
between the supply side and discharge
side.
Ifthe
temperature difference is
8 degrees
or
less,
consideration should then be
given to cleaning
the
water coil heat exchanger.
II. If
cleaning
of
the water
coil is indicated,
please
carefully follow
the steps listed
below
to
utilize
the freeze
cleaning method.
1.
Turn off
the heat
pump
and
its water supply.
2.
Open
a
plumbing
connection on the water supply
side,
if
possible,
to
break the
system
vacuum
and
allow
easier
drainage
of
the system and water
coil.
3.
Drain
the
water out of
the system and
water coil
via the
boiler
drains on the entering and
leaving
water lines, and the drain on the heat exchanger.
EWARNING!!
g
FAILURE TO COMPLETELY
DRAIN THEWATER
COIL
HEAT
EXCHANGER
COULD POSSIBLY RESULT
IN A
FREEZE
RUPTLIRE!
4.
Set the
thermostat
to "Heat" to
start the heat
pump
in
the
heating mode
and
quickly
freeze the
coil.
5.
Allow
the heat
pump to run
until it
automatically
shuts
off
on
low
pressure and then turn
the
thermostat to
the
"Off'position.
6.
Recap the
water drains
and
tighten any
plumbing
connections that may have been loosened.
7.
If
so
equipped,
open the
field installed drain cock
on the water discharge side
of
the heat
pump,
and
install
a short
piece of
rubber hose
to allow
drainage
into
a
drain or
bucket. A
drain cock on
the
discharge side allows the water
flow
to
blpass
the
solenoid valve,
flow
valve,
flow
meter, or
any
other item that
may be
clogged by mineral
debris.
Drainage to
a
bucket
helps
prevent
the
clogging
of
drains
and
allows you to
visually
determine
the
effectiveness of
the
procedure.
8.
Turn
on
the water supply to
the heat
pump
in
order
to
start the process of
flushing
any mineral debris
from
the
unit.
9.
Set the
thermostat to
"Cool"
and start the heat
pump in
the
cooling mode
to quickly
thaw out the
water coil.
10.
Run
the heat
pump until
the
water coil
is
completely thawed out
and any loosened
scale,
mineral deposits, or other debris buildup
is flushed
completely from
the
water
coil.
Allow
at least
5
minutes
of
operation to
ensure
that
the
water
coil
is
thoroughly
thawed
out.
I 1.
If
ttre
water
still
contains mineral debris,
and
if
the
flow
through
the
unit did not improve
along
with
an increase
in
the temperature difference between
the
water supply
and discharge, repeat the
entire
procedure listed
above.
12. Reset the heat
pump for
normal operation.
b. Chlorine Cleaning
(Bacterial Growth)
1.
Turn
the
thermostat to the
"Off'position.
2.
Connect a submersible
circulating pump to
the
hose bibs
on the
entering
and
leaving water
sides
of
the heat exchangers.
3.
Submerse the
pump
in
a
five-gallon pail of
water
and chlorine bleach
mixture.
The chlorine should
be sftong
enough
to
kill
the
bacteria.
Suggested
initial
mixture is
1
part chlorine bleach to
4
parts
water.
4.
Close the shut
off
valves upstream and
downsffeam
of
the heat exchanger.
5.
Open the hose
bibs to allow circulation of
the
bleach solution.
6.
Start
fhe
pump
and
circulate
the
solution through
the heat exchanger
for
15 minutes to one hour.
The solution should
change
color
to indicate
the
chlorine is
killing
the bacteria and
removing
it
from
the heat exchanger.
7.
Flush
the used
solution down
a
drain by adding
a
fresh water supply to
the
pail.
Flush
until
the
leaving water is
clear.
8.
Repeat
this procedure until
the solution runs clear
through
the
chlorine circulation process.
9.
Flush the entire
heat
pump
system
with
water.
This procedure
can be repeated annually, semiannually, or
as
often
as
it
takes
to
keep
bacteria out
ofthe
heat
exchanger, or when bacteria
appezlrs
in
a
visual flowmeter
to the
point
the
flow
cannot be read.
Another alternative to bacteria problems is
to
shock
your
entire
wel1. Shocking your well may give longer term
relief from bacteria problems than cleaning your
heat
exchanger, but
will
probably
need to be repeated, possibly
every three to
five years. SContact
a
well driller in your
area
for
more
information.
7