Water-Source Heat Pump (Hp) - Greenheck ERCH-20 Installation, Operation And Maintenance Manual

Water-Source Heat Pump with Standard Scroll Compressor
Water Out Water In
12
Supply
Airflow
1. Compressor
2. High Limit Pressure Switch
3. Hot Gas Reheat Valve (optional)
4. Hot Gas Reheat Coil
5. Hot Gas Reheat Check Valve
6. Liquid Receiver (optional)
7. Liquid Line Filter Drier
8. Thermostatic Expansion Valve (TXV)
9. Low Limit Pressure Switch
10. Hot Gas Bypass Valve (optional)
On units equipped with hot gas bypass, hot gas
from the compressor is injected into the refrigerant
line of the evaporator coil after the TXV.
11. Airside Coil
Each unit uses a single refrigerant coil known as
an airside coil. If two compressors are used in the
unit, then the airside coil will be a split configuration
so that each compressor has a dedicated portion
of the airside coil. Depending on whether the
unit is in cooling or heating mode, the airside coil
will function as either a condensing coil or an
evaporator coil.
28 Energy Recovery Ventilator with Heating and Cooling General Description - NOT model specific
5
10
5
4
8
12. Coaxial Refrigerant-to-Water Heat Exchanger
13. Reversing Valves
13
9
11
6
The unit uses one coaxial heat exchanger per
compressor, essentially a tube inside a tube.
Water flows through the inner copper tube and
compressed refrigerant is forced through the
spaces between the inner and outer tubes.
Depending on whether the unit is functioning in a
cooling or a heating capacity, heat is rejected from
one tube to the other.
Each compressor is equipped with a reversing
valve to reverse the direction of refrigerant flow.
Changing refrigerant flow allows the unit to operate.
3
2
1
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