Service manual

THE SMART SOLUTION FOR ENERGY EFFICIENCY
Vertical Stack
Rev.: 11/09/12
17
climatemaster.com
Open Loop - Ground Water Systems - Shut off valves
should be included for ease of servicing. Boiler drains or
other valves should be “tee’d” into the lines to allow acid
fl ushing of the heat exchanger. Shut off valves should be
positioned to allow fl ow through the coax via the boiler
drains without allowing fl ow into the piping system.
P/T plugs should be used so that pressure drop and
temperature can be measured. Supply and return water
piping materials should be limited to copper, PE, or similar
material. PVC or CPVC should never be used as they are
incompatible with the POE oils used in HFC-410A products
and piping system failure and property damage may result.
Water quantity should be plentiful and of good quality.
Consult Table 4 for water quality guidelines. The unit can
be ordered with either a copper or cupro-nickel water
heat exchanger. Consult Table 4 for recommendations.
Copper is recommended for closed loop systems and
open loop ground water systems that are not high
in mineral content or corrosiveness. In conditions
anticipating heavy scale formation or in brackish water, a
cupro-nickel heat exchanger is recommended. In ground
water situations where scaling could be heavy or where
biological growth such as iron bacteria will be present, an
open loop system is not recommended. Heat exchanger
coils may over time lose heat exchange capabilities due
to build up of mineral deposits. Heat exchangers must
Ground-Water Heat Pump Applications
 CAUTION! 
CAUTION! Many units are installed with a factory or fi eld
supplied manual or electric shut-off valve. DAMAGE WILL
OCCUR if shut-off valve is closed during unit operation. A
high pressure switch must be installed on the heat pump side
of any fi eld provided shut-off valves and connected to the
heat pump controls in series with the built-in refrigerant circuit
high pressure switch to disable compressor operation if water
pressure exceeds pressure switch setting. The fi eld installed
high pressure switch shall have a cut-out pressure of 300
psig and a cut-in pressure of 250 psig. This pressure switch
can be ordered from ClimateMaster with a 1/4” internal fl are
connection as part number 39B0005N02.
WARNING! Polyolester Oil, commonly known as POE oil, is
a synthetic oil used in many refrigeration systems including
those with HFC-410A refrigerant. POE oil, if it ever comes
in contact with PVC or CPVS piping, may cause failure of
the PVC/CPVC. PVC/CPVC piping should never be used
as supply or return water piping with water source heat
pump products containing HFC-410A as system failures and
property damage may result.
 WARNING! 
only be serviced by a qualifi ed technician, as acid and
special pumping equipment is required. Desuperheater
coils can likewise become scaled and possibly plugged.
In areas with extremely hard water, the owner should be
informed that the heat exchanger may require occasional
acid fl ushing. In some cases, the desuperheater
option should not be recommended due to hard water
conditions and additional maintenance required.
Water Quality Standards - Table 4 should be consulted
for water quality requirements. Scaling potential should
be assessed using the pH/Calcium hardness method.
If the pH <7.5 and the calcium hardness is less than
100 ppm, scaling potential is low. If this method yields
numbers out of range of those listed, the Ryznar Stability
and Langelier Saturation indecies should be calculated.
Use the appropriate scaling surface temperature for the
application, 150°F [66°C] for direct use (well water/open
loop) and DHW (desuperheater); 90°F [32°F] for indirect
use. A monitoring plan should be implemented in these
probable scaling situations. Other water quality issues
such as iron fouling, corrosion prevention and erosion
and clogging should be referenced in Table 4.
Expansion Tank and Pump - Use a closed, bladder-
type expansion tank to minimize mineral formation due
to air exposure. The expansion tank should be sized to
provide at least one minute continuous run time of the
pump using its drawdown capacity rating to prevent
pump short cycling. Discharge water from the unit is not
contaminated in any manner and can be disposed of in
various ways, depending on local building codes (e.g.
recharge well, storm sewer, drain fi eld, adjacent stream
or pond, etc.). Most local codes forbid the use of sanitary
sewer for disposal. Consult your local building and
zoning department to assure compliance in your area.
Water Control Valve - Always maintain water pressure in
the heat exchanger by placing the water control valve(s)
on the discharge line to prevent mineral precipitation
during the off-cycle. Pilot operated slow closing valves
are recommended to reduce water hammer. If water
hammer persists, a mini-expansion tank can be mounted
on the piping to help absorb the excess hammer shock.
Ensure that the total ‘VA’ draw of the valve can be
supplied by the unit transformer. For instance, a slow
closing valve can draw up to 35VA. This can overload
smaller 40 or 50 VA transformers depending on the other
controls in the circuit. A typical pilot operated solenoid
valve draws approximately 15VA.