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HOT GAS REHEAT (Optional) — Terminal H is active in
dehumidification mode with hot gas reheat. After a call for H,
the reversing valve (O), compressor (Y), and fan (G) are also
enabled.
NOTE: Any call for cooling (Y), heating (Y or W), or revers-
ing valve (O) will override dehumidification mode (H).
WATERSIDE ECONOMIZER (Optional) — Y and O ter-
minals are active in Cooling mode. When the entering water
temperature drops below the entering water temperature set
point on the waterside economizer aquastat, the compressor
and reversing valve are disabled and the waterside economizer
is enabled. The waterside economizer three way control valve
will divert water to the economizer coil for free cooling. When
the entering water temperature rises above the aquastat set
point, the waterside economizer is disabled and the compressor
and reversing valve are enabled.
TWO WAY WATER FLOW CONTROL VALVE
(Optional) — The two way water flow control valve is
enabled anytime there is a call for cooling (Y), heating (Y), or
dehumidification (H) and allows water to flow through the
unit. When there is no call for cooling, heating, or dehumidifi-
cation, the water flow control valve is disabled, stopping flow
through the unit.
BOILERLESS HEAT (Deluxe D Only) — When the enter-
ing water temperature is below the boilerless heat aquastat
entering water temperature set point and there is a call for heat-
ing (Y), the compressor is disabled and the auxiliary heat out-
put is enabled. When the entering water temperature is above
the aquastat set point, the auxiliary heat output is disabled and
the compressor is enabled.
PUMP/VALVE RELAY (Deluxe D Only) — The pump/
valve relay is enabled anytime there is a call for cooling (Y),
heating (Y), or dehumidification (H) and can be used to
enable/disable field installed flow control valves or circulator
pumps. When there is no call for cooling, heating, or dehumid-
ification, pump/valve relay is disabled.
Units with WSHP Open Controls with UPM
Board —
Units with WSHP Open still feature a UPM board
for unit operation, so the operation will be similar to the
sequence for the Complete C and Deluxe D package. WSHP
Open does feature advanced functionality, such as automatic
fan speed control and intelligent alarming, which will differ
from the Complete C and Deluxe D packages. For WHSP
Open operation, please refer to the WSHP Open Integration
Guide and the WSHP Points/Properties Manual.
SERVICE
Perform the procedures outlined below periodically, as
indicated.
An annual “checkup” is recommended by a licensed refrig-
eration mechanic. Recording the performance measurements
of volts, amps, and water temperature differences (both heating
and cooling) is recommended. This data should be compared to
the information on the unit’s data plate and the data taken at the
original start-up of the equipment.
Periodic lockouts almost always are caused by air or water
flow problems. The lockout (shutdown) of the unit is a normal
protective measure in the design of the equipment. If continual
lockouts occur call a mechanic immediately and have them
check for: water flow problems, water temperature problems,
airflow problems or air temperature problems. Use of the pres-
sure and temperature charts for the unit may be required to
properly determine the cause.
Filters —
Filter changes or cleanings are required at regular
intervals. The time period between filter changes will depend
upon type of environment the equipment is used in. In a single
family home, that is not under construction, changing or clean-
ing the filter every 60 days may be sufficient. In other applica-
tions such as motels, where daily vacuuming produces a large
amount of lint, filter changes may be need to be as frequent as
biweekly. See Fig. 1-3 for replacement filter sizes. Note that
horizontal units containing two filters are taped together at the
factory to facilitate removal. This should be done by end user
as new filters are installed.
Condensate Drain Pans —
The condensate drain
should be checked annually by cleaning and flushing to ensure
proper drainage.
Refrigerant System —
Verify air and water flow rates
are at proper levels before servicing. To maintain sealed circuit-
ry integrity, do not install service gages unless unit operation
appears abnormal. Check to see that unit is within the super-
heat and subcooling temperature ranges shown in Tables 14-
25. If the unit is not within these ranges, recover and reweigh in
refrigerant charge.
Compressor —
Conduct annual amperage checks to en-
sure that amp draw is no more than 10% greater than indicated
on the serial plate data.
Fan Motors —
All units have lubricated fan motors. Fan
motors should never be lubricated unless obvious, dry opera-
tion is suspected. Periodic maintenance oiling is NOT recom-
mended as it will result in dirt accumulating in the excess oil
and cause eventual motor failure. Conduct annual dry
operation check and amperage check to ensure amp draw is
no more than 10% greater than indicated on serial plate data.
IMPORTANT: When a compressor is removed from this
unit, system refrigerant circuit oil will remain in the com-
pressor. To avoid leakage of compressor oil, the refrigerant
lines of the compressor must be sealed after it is removed.
WARNING
To avoid injury and the discharge of refrigerant into the
environment, all refrigerant discharged from this unit must
be recovered without exception. Technicians must follow
industry accepted guidelines and all local, state and federal
statutes for the recovery and disposal of refrigerants.
WARNING
To avoid injury and the release of refrigerant into the atmo-
sphere, the refrigerant circuit of this unit must only be ser-
viced by technicians who meet local, state and federal
proficiency requirements.
WARNING
To prevent injury or death due to electrical shock or contact
with moving parts, open unit disconnect switch before ser-
vicing unit.
IMPORTANT: Units should never be operated without
a filter.
CAUTION
Equipment should never be used during construction due to
likelihood of wall board dust accumulation in the air coil of
the equipment which permanently affects the performance
and may shorten the life of the equipment.