Manual 2100-583G
Page
20 of 48
SYSTEM START UP PROCEDURE FOR
GROUND WATER APPLICATIONS
1. Be sure main power to the unit is OFF at disconnect.
2. Set thermostat system switch to OFF.
3. Move main power disconnect to ON. Except as
required for safety while servicing –
DO NOT
OPEN THE UNIT DISCONNECT SWITCH
.
4. Fully open the manual inlet & outlet valves, and
manually open water solenoid valve on the source side.
5.
Check water flow.
a. Connect a water flow meter to the drain cock
between the constant flow valve and the solenoid valve.
b. Check the water flow rate through the constant flow
valve and the solenoid valve. Run a hose from the
flow meter to a drain or sink. Open the drain cock.
c. When water flow is okay, close the drain cock and
remove the water flow meter. The unit is now ready
to start.
6. Start the unit in heating mode by switching on the
Aquastat.
a. Make sure the water solenoid valve actuated/
opened.
7. Check the system refrigerant pressures against the
refrigerant pressure table located on the backside
of the system service door at the corresponding
source and load flow rates and enetering water
temperatures. If the refrigerant pressures do not
match, check for water flow issues, and then a
refrigeration system problem.
8. Switch the Aquastat/thermostat to cooling mode
and again verify water solenoid actuation, and
refrigerant pressures.
NOTE:
If a charge problem is determined (high or low):
A. Check for possible refrigerant loss.
B. Reclaim all remaining refrigerant.
C. Evacuate unit down to 29" of vacuum.
D. Recharge unit with refrigerant by weight to the serial
plate, as this is the only way to ensure proper charge.
WATER CORROSION
Two concerns will immediately come to light when
considering a water source heat pump, whether for ground
water or for a ground loop application: Will there be enough
water? And, how will the water quality affect the system?
Water quantity is an important consideration and one which
is easily determined. The well driller must perform a pump
down test on the well according to methods described
by the National Well Water Association. This test, if
performed correctly, will provide information on the rate
of flow and on the capacity of the well. It is important to
consider the overall capacity of the well when thinking
about a water source heat pump because the heat pump
may be required to run for extended periods of time.
The second concern, about water quality, is equally
important. Generally speaking, if the water is not offensive
for drinking purposes, it should pose no problem for
the heat pump. The well driller or local water softening
company can perform tests which will determine the
chemical properties of the water.
Water quality problems will show up in the heat pump in
one or more of the following ways:
•
Decrease in water flow through the unit.
• Decreased heat transfer of the water coil (entering to
leaving water temperature difference is less).
There are four main water qualtiy problems associated with
ground water. These are:
1.
Biological Growth
This is the growth of microscopic
organisms in the water and will show up as a slimy deposit
throughout the water system. Shock treatment of the well
is usually required and this is best left to the well driller.
The treatment consists of injecting chlorine into the well
casing and flushing the system until all growth is removed.
2.
Suspended Particles in the Water
Filtering will
usually remove most suspended particles (fine sand, small
gravel) from the water. The problem with suspended
particles in the water is it will erode metal parts, pumps,
heat transfer coils, etc. As long as the filter is cleaned and
periodically maintained, suspended particles should pose
no serious problem. Consult with your well driller.
3.
Corrosion of Metal
Corrosion of metal parts results
from either highly corrosive water (acid water, generally
not the case with ground water), or galvanic reaction
between dissimilar metals in the presence of water. By
using plastic plumbing or dielectric unions, galvanic
reaction is eliminated. The use of corrosion resistant
materials such as a Cupronickel Water Coil through the
water system will reduce corrosion problems significantly.
4.
Scale Formation
Of all the water problems, the
formation of scale by ground water is by far the most
common. Usually due to the formation of calcium
carbonate, but magnesium carbonate or calcium sulfate
may also be present. Carbon dioxide gas (CO2), the
carbonate of calcium and magnesium carbonate, is very
soluble in water. It will remain dissoved in the water
until some outside factor upsets the balance. This outside
influence may be a large change in water temperature or
pressure. When this happens, enough carbon dioxide gas
combines with the dissolved calcium or magnesium in
the water and falls out of solution until a new balance is
reached. The change in temperature that this heat pump
produces is usually not high enough to cause the dissoved
gas to fall out of solution. Likewise, if pressure drops
are kept to a reasonable level, no precipitation of carbon
dioxide should occur.
GROUND WATER (WELL SYSTEM APPLICATIONS)
