T Therm Geo TST-***, Инструкция по установке и эксплуатации

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12/03/2012
41 GI301
Troubleshooting – GEO Logic Control
Sensor Temperature Calibration
– all four remote sensors are digital electronic and factory calibrated.
Normally these do not require field calibration or verification. However, if sensor temperature error is
determined, use the special PC software and PC USB port cable to set the appropriate offset.. The PC screen has
direct readout of the four monitored temperatures, it allows a visual determination of temperature settings, and
can be used to offset the temperature sensors for troubleshooting and demonstration purposes.
NOTE
Temperature Sensors
Temperature sensors installed in TTHERM GEO heat pumps
are NOT thermisters
. They are digital devices
calibrated at the manufacturer. They are polarity sensitive. Be sure to connect the red and white wires in their
correct shared terminals. The black wire is the data stream wire and will have its own screw terminal.
Bad sensor, safety
– if the internal logic detects open sensor wire, a shorted sensor wires, or a incorrectly wired
sensor; the green POWER LED reverts to a pulsing mode. See Operational Indicators.
Bad sensor, operating default condition
– the detection of bad sensor forces the controller to a fixed stage
operation. Software declared bad sensor default
ST = 70° F LWT (heating) = 32°F LWT (cooling) = 77° F
CDT = 200° F (DDT = 190° F (CDT on dual compressor models = 200°F)).
Check the GEO Logic Controller, Operational Indicators, section of this manual for in depth description of the
diagnostic information available by observing the LED’s.
Internal fuses –
the source loop, hydronic loop pumps, and desuperheater pump are fused on the high voltage
pump relay board.
 The pump hookup decal provides the fuse size and details.
 The GEO Logic controller is protected by the circuit breaker on the low voltage transformer.
Troubleshooting/Repair Helps
1. This GEO Logic controller contains several interference suppression components, but as an electronic
logic product, unpredictable and unusual transients or interferences may sometimes cause strange
results. If the GEO Logic controller is “acting strange”, one immediate step would be a power down
reset. Simply turn off the 240 volt source power. When the green POWER LED goes out, count to 10,
and re-energize power supply.
2. The terminal blocks for control wire hook-up are designed for a wire insertion and screw clamp down.
If there is no wire connected and the screw is loose, the screw may not necessarily make a good
electrical contact to the inside components. Example – if you jumper the thermostat terminals without
thermostat wire connection or if you are attempting to measure voltage on the screw head, you may get
erroneous or unpredictable results if the screw is not tightened down.
3. The THT, dual compressor units, have two separate refrigerant circuits. Each compressor has its own
refrigerant circuit. The high pressure switches and low pressure switches in both circuits are wired in
series. If the heat pump locks out low pressure or high pressure, each of the refrigerant circuits will need
the pressures monitored to determine which circuit caused the lockout.
4. Use general heating/heat pump system logic information and basic understanding of the terminal block
wiring functions when measuring voltage to determine proper operation.
Open Loop Operation –
TTHERM GEO heat pumps are factory set for open loop operation. Open/Closed loop
operation is set with
Jumper J 11
on the left side of the GEO Logic controller. The jumper must be in place on
J11 if the unit is operated on an open loop. The GEO Logic controller protects the heat exchanger from freezing
by causing the compressor to shut down when the leaving water temperature reaches 38° F open loop and 20° F
closed loop. The compressor will remain off for 2 ACD’s, and the EARTH LOOP FLOW/ SOURCE WATER
LIMIT & HP STAGE 1 LED’s will pulse, while the water runs and warms up. The compressor will then restart
again providing heat until the LWT again reaches 38° F open loop and 20° F closed loop. If this