Open Well Water Systems; Water Quality - Bosch LV009 Installation And Maintenance Manual

22 | Water Quality

Open Well Water Systems

When a water well is used exclusively for supplying
water to the heat pump, the pump should operate only
when the Heat Pump operates. A 24 volt, double pole
single throw (DP/ST) contactor can be used to operate
the well pump with the heat pump. When two or more
units are supplied from one well, the pump can be wired
to operate independently from either unit. Two 24-volt
double pole single trow relays wired in parallel are
required.
An up size VA transformer may be required in either
case. The discharge water from the heat pump is not
contaminated in any manner and can be disposed of in
various ways depending on local codes (i.e. discharge
well, dry well, storm sewer, drain field, stream, pond,
etc.)
Figure # 18 Well Water Applications
1. Line Voltage Disconnect
2. Flex Duct Connector
3. Low Voltage Control Connection
4. Line Voltage Connection
5. Vibration Pad
6. P/T Ports
7. Hose Kits (Optional)
8. Ball Valves
9. Solenoid Valve Slow Closing
10. Condensate Drain Connection
11. Pressure Tank (Optional)
8 733 944 336 (2016/09)
WATER QUALITY
NOTICE: Failure to ensure proper water
quality and flow rates can shorten the life of
the heat pump and potentially void the unit
warranty.
Maintaining proper water quality is important for
ensuring a long service life for an LV series heat pump.
For closed loop and boiler/tower systems water
chemistry can be checked and easily maintained to
ensure that corrosive elements, dissolved oxygen and
pH levels are kept in check. It is important to ensure that
any additive, antifreeze or corrosion inhibitor that is
added to the water loop is compliant with all applicable
laws and regulations and is compatible with copper,
brass and bronze alloys. ensure that all recommended
safety precautions are followed when handling or adding
chemicals to the water loop.
For open loop systems, water quality is very important.
Refer to the Water Quality Table on page# 21, for
acceptable ranges for a variety of water quality factors.
The three main concerns in open loop installations are
scaling, corrosion and fouling.
In installations with hard water, scaling due to a buildup
of carbonates on the heat exchanger wall can gradually
degrade the heat pump performance over time.
Heat pumps that are affected by scaling may exhibit low
suction pressures in heating and high head pressures in
cooling with a gradual loss of capacity and efficiency.
Scaled heat exchangers can be cleaned by a qualified
technician but care should be taken to avoid scaling in
the first place.
To limit scaling, water flow rates should be kept at 3
gallons/minute per nominal cooling ton (a 10°F
temperature rise in cooling) and care should be taken to
avoid air in the water lines from suction side leaks.
Cupro-nickel coils are generally recommended.
In installations with high hydrogen sulfide, chlorine or
ammonia, corrosion is a potential problem. In these
installations a cupro-nickel heat exchanger is required
along with maintaining proper flow and keeping air out
of the system. If water quality is outside of the values in
the water quality table, then a closed loop is required.
Fouling due to iron bacteria can also pose problems in
some open loop installations. Iron bacteria fouling can
quickly degrade system performance and plug heat
exchangers.
Air in the water system will greatly accelerate the fouling
or corrosion process.
Subject to change without prior notice
LV Heat Pump Series
LV Heat Pump Series