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R e s i d e n t i a l D i g i t a l P a c k a g e d U n i t s G T- P B S e r i e s - 6 0 H z P u ro n
®
R e v : 4 A p r i l , 1 4
Unit Start-Up and Operating Conditions
CAUTION!
CAUTION!
CAUTION!
To avoid equipment damage, DO NOT
leave system
fi
lled in a building without heat during the
winter unless antifreeze is added to the water loop. Heat
exchangers never fully drain by themselves and will
freeze unless winterized with antifreeze.
CAUTION!
Verify that ALL water valves are open and
allow water
fl
ow prior to engaging the compressor.
Freezing of the coax or water lines can permanently
damage the heat pump.
Unit Start-up Procedure
1. Turn the thermostat fan position to “ON.” Blower should
start.
2. Turn Blower off.
3. Ensure all valves are adjusted to their full open position.
Ensure line power to the heat pump is on.
4. Room temperature should be within the minimum-
maximum ranges of listed in the unit IOM. During start-
up checks, loop water temperature entering the heat
pump should be between 30°F [-1°C] and 95°F [35°C].
5. It is recommended that water-to-air units be
fi
rst started
in the cooling mode, when possible. This will allow liquid
refrigerant to
fl
ow through the
fi
lter-drier before entering
the TXV, allowing the
fi
lter-drier to catch any debris that
might be in the system before it reaches the TXV.
6. Two factors determine the operating limits of geothermal
heat pumps, (a) return air temperature, and (b) entering
water temperature. When either of the factors is at a
minimum or maximum level, the other factor must be at
normal levels to insure proper unit operation.
a. Place the unit in Manual Operation. When in manual
mode activate Y1,Y2, and O to initiate the cooling
mode. Also manually increase CFM until desired
cooling CFM is achieved. Next adjust pump speed
% until desired loop temperature difference (leaving
water temperature minus entering water temperature)
is achieved. (For modulating valve adjust valve %).
INSTALLER SETTINGS
THERMOSTAT CONFIG
SYSTEM CONFIG
ACCESSORY CONFIG
INPUT DEALER INFO
HUMIDITY CONFIG
TEMPERATURE CONTROL
DEMAND REDUCTION CNFG
SERVICE MODE
SETPOINT LIMITS
RESTORE DEFAULTS
DXM2 3.3
ATC32U02 C 1.0
SELECT OPTION
PREVIOUS
Unit and System Checkout
BEFORE POWERING SYSTEM, please check the following:
UNIT CHECKOUT
Shutoff valves: Insure that all isolation valves are open.
Line voltage and wiring: Verify that voltage is within
an acceptable range for the unit and wiring and fuses/
breakers are properly sized. Verify that low voltage wiring
is complete.
Unit control transformer: Insure that transformer has the
properly selected voltage tap. Residential 208-230V units
are factory wired for 230V operation unless speci
fi
ed
otherwise.
Loop/water piping is complete and purged of air. Water/
piping is clean.
Antifreeze has been added if necessary.
Entering water and air: Insure that entering water and air
temperatures are within operating limits of Tables 10a
and 10b.
Low water temperature cutout: Verify that low water
temperature cut-out on the DXM2 control is properly set.
Unit fan: Manually rotate fan to verify free rotation and
insure that blower wheel is secured to the motor shaft.
Be sure to remove any shipping supports if needed.
DO NOT oil motors upon start-up. Fan motors are pre-
oiled at the factory. Check unit fan CFM selection and
compare to design requirements.
Condensate line: Verify that condensate trap is installed
and pitched.
HWG is switched off at SW 3-4 unless piping is
completed and air has been purged from the system.
Unit air coil and
fi
lters: Insure that
fi
lter is clean and
accessible. Clean air coil of all manufacturing oils.
Unit controls: Verify that DXM2
fi
eld selection options are
properly set. Low voltage wiring is complete.
Blower CFM and Water
∆
T is set on communicating
thermostats or diagnostic tool.
Service/access panels are in place.
SYSTEM CHECKOUT
System water temperature: Check water temperature
for proper range and also verify heating and cooling set
points for proper operation.
System pH: Check and adjust water pH if necessary to
maintain a level between 6 and 8.5. Proper pH promotes
system longevity (see Table 5).
System
fl
ushing: Verify that all air is purged from the
system. Air in the system can cause poor operation or
system corrosion. Water used in the system must be
potable quality initially and clean of dirt, piping slag,
and strong chemical cleaning agents. Some antifreeze
solutions may require distilled water.
Internal Flow Controller: Verify that it is purged of air and
in operating condition.
System controls: Verify that system controls function and
operate in the proper sequence.
Low water temperature cutout: Verify that low water
temperature cut-out controls are set properly
(LT1 - JW3).
Miscellaneous: Note any questionable aspects of
the installation.