T Therm Geo TST-*** Installation & Operating Instructions Manual

Two-stage split geothermal heat pump

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Two-Stage Split Geothermal Heat Pump

Installation & Operating Instructions

Application



Retrofit existing forced air installations



Dual Heat – combine this geothermal unit and A-coil with standby

gas or oil furnace



LMC (Load management control), LMC/INT ready



Tested to UL Standards 1995

Information

The air coil furnished with this product has been tested and certified

with this unit. To maintain the specification performance and product

certification, the air coil shipped with this unit must be used.

This unit may not be tax credit eligible when a coil other than the

furnished coil is used.

For optimum performance an ECM blower is recommended. The CFM airflow required in the

specification table must be matched to the compressor stage by the installed furnace blower/air handler.

Since this product requires line sets and air coil installation, an experienced and licensed refrigeration

technician is required.

Domestic Water Heater, Desuperheater

Energy Star promotes the desuperheater and it is offered as an optional item for all TTHERM GEO™

heat pumps. Our exclusive GEO Logic™ control system optimizes the operation of a desuperheater,

operating the systems only when there is adequate energy available to provide heat to the domestic hot

water. However, to maximize the times the desuperheater aides in providing domestic hot water, a hot

water preheat tank is suggested, see Desuperheater section of this manual.

Note – The GEO Logic control board has various required setup adjustments, see Field Setup section.

DO NOT DESTROY THIS MANUAL. PLEASE READ CAREFULLY AND KEEP IN A

SAFE PLACE FOR FUTURE REFERENCE BY A SERVICE TECHNICIAN.

12/03/2012

Model: (TST-***)

Important information

Model Number:____________________________

Serial Number:_____________________________

Installing Contractor:________________________

GI301

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Summary of Contents for T Therm Geo TST-***

Page 1 Two-Stage Split Geothermal Heat Pump Installation & Operating Instructions Model: (TST-***) Application  Retrofit existing forced air installations  Dual Heat – combine this geothermal unit and A-coil with standby gas or oil furnace  LMC (Load management control), LMC/INT ready ...
Page 2: Table Of Contents
Table of Contents Introduction Product Configurator (GC002) Mechanical Specifications Electrical Data Product Dimensions Installation Requirements Mechanical Installation Overview Mechanical Installation Source Water Desuperheater, Domestic Hot Water Duct System/A-Coil Installation Installing the TXV Mechanical Installation Refrigeration Charging Procedure Superheat and Sub-Cooling Unit Operating Conditions Heat &...
Page 3: Introduction
Introduction Geothermal heat pumps are able to heat and cool spaces with efficiencies exceeding 350% by taking advantage of solar heat stored in the earth’s crust and the earth’s relatively stable temperatures. In the winter time, heat is moved from the earth into the home and concentrated using a refrigeration system. Since the heat already exists in the soil, the cost of operation of the geothermal heat pump is, in effect transportation cost for the free heat.
Page 4: Safety Considerations
Safety Considerations WARNING BEFORE PERFORMING SERVICE OR MAINTENANCE OPERATIONS ON A SYSTEM, TURN OFF MAIN POWER SWITCHES TO THE INDOOR UNIT. IF APPLICABLE, TURN OFF THE ACCESSORY HEATER POWER SWITCH. ELECTRICAL SHOCK COULD CAUSE PERSONAL INJURY. Installing and servicing heating and air conditioning equipment can be hazardous due to system pressure and electrical components.
Page 5: Product Configurator (Gc002)
TTHERM GEO Heat Pump Configurator T V T - 0 4 8 - 1 C L D X 1 - X X Model Number Digits TVT-048-1CLDX1-XX TTHERM GEO (1) Auxiliary kW Option* (13, 14) 05 = 4.8 kW Unit Style (2) 10 = 9.6 kW C = Combo 15 = 14.4 kW...
Page 6: Mechanical Specifications
Mechanical Specifications – R410A Two-Stage Compressor TST-024 TST-036 TST-048 TST-060 MODEL (2 ton) (3 ton) (4 ton) (5 ton) Coax & Piping Water Volume – gal Source Temperature °F (min/max) 20°/120° 20°/120° 20°/120° 20°/120° Nominal source differential* ° F (H/C) 3/12°...
Page 7: Electrical Data
Electrical Data – Single Phase Loop Desup. Max. Voltage Compressor Pump Total Min. Pump Model Fuse/ (Ext) HACR (60 Hz) Ampac. TST-024 208/230-1 13.1 73.0 17.7 20.9 TST-036 208/230-1 17.9 22.5 26.9 TST-048 208/230-1 27.1 152.9 31.6 38.2 TST-060 208/230-1 29.7 179.2 34.3...
Page 8: Product Dimensions
Product Dimensions Forced Air Coil – Reference Information GI301 12/03/2012...
Page 9: Installation Requirements
Installation Requirements 1. All installation work must be performed by trained, qualified contractors or technicians. TTHERM GEO Heat Pump, sponsors installation and service schools to assist the installer. Contact TTHERM GEO at sales@tthermgeo.com for upcoming dealer training events. WARNING ALL ELECTRICAL WIRING MUST BE IN ACCORDANCE WITH NATIONAL ELECTRIC CODE AND LOCAL ELECTRIC CODES, ORDINANCES, AND REGULATIONS.
Page 10: Mechanical Installation Overview
Mechanical Installation Overview This TTHERM GEO series unit cannot correct airflow problems inherent within the duct work system. The following items should be carefully considered and properly followed for all installations: Examination of the existing forced air furnace – Prior to starting this installation or furnace modification, examine the total furnace system and make necessary comments or recommendations to the homeowner.
Page 11 equivalent duct capacity airflow charts and determine if the system is capable of delivering the CFM required on the nameplate. Especially check the number of registers and the number of “6 inch rounds”. The same would apply to cold air return duct capacity. d.
Page 12 Closed Loop Applications – Closed loop system re-circulates the same water/antifreeze solution through a closed system of underground high-density polyethylene pipe. As the solution passes through the pipe it collects heat (in the heating mode) that is being transferred from the relatively warm surrounding soil through the pipe and into the relatively cold solution.
Page 13: Mechanical Installation Source Water
Mechanical Installation Source Water WARNING LOOP DESIGN IS EXTREMELY IMPORTANT FOR PROPER HEAT PUMP OPERATION. INCORRECT LOOP DESIGN WILL REDUCE HEAT PUMP EFFICIENCY, CAUSE POOR PERFORMANCE OR MAY RENDER THE SYSTEM UNUSABLE. IF YOU LACK EXPERIENCE DESIGNING LOOP FIELDS, CONTACT AN IGSHPA OR CGC CERTIFIED GEOTHERMAL LOOP CONTRACTOR FOR PROPER INSTALLATIONS.
Page 14 Figure 4 – Non-Pressurized Closed Loop with Flow Center – Typical piping arrangement. Figure 5 – Pressurized Closed Loop with Flow Center – Typical piping diagram. GI301 12/03/2012...
Page 15 Antifreeze When considering the earth loop solution, water quality is very important. TTHERM GEO recommends a minimum of soft water (not well water) treated with 2 oz. of household chlorine bleach for each 10 gallons of total volume. TTHERM GEO’s recommended antifreeze concentration is 22% which will yield a freeze protection of 18°...
Page 16 heat pump a flow meter is installed to provide a visual indicator of open loop flow in GPM. The water solenoid valve must be installed to control water flow through the unit. After the water solenoid a flow control valve is installed to limit maximum flow through the heat pump.
Page 17 Open Loop – Typical piping diagram. Figure 6: Note TTHERM GEO heat pumps are factory set for open loop operation. Open Loop Operation – TTHERM GEO heat pumps are factory set for open loop operation. Open or Closed loop operation is set with jumper J11 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.
Page 18: Desuperheater, Domestic Hot Water
Desuperheater, Domestic Hot Water General TTHERM GEO series units may be equipped with a double wall desuperheater and an integrated circulating pump that can provide Supplemental Domestic hot Water (SDW). This is done by stripping heat from the superheated gas leaving the compressor. Fuses –...
Page 19 Figure 7 – Desuperheater Piping, preheat Tank This is the most effective and efficient arrangement for high hot water needs. This is also the recommended method when using a gas water heater with a desuperheater. The preheat tank need not be as big as the standard water heater; 40- gallon size can be very effective.
Page 20: Duct System/A-Coil Installation
Duct System An air filter must always be installed upstream of the air coil on the return air side of the air handler or furnace. If there is limited access to the filter rack for normal maintenance, it is suggested that a return air filter grill be installed.
Page 21: Installing The Txv
Coil in Supply Plenum Method Coil in Return Ductwork Method Installing the TXV on TTHERM GEO TST Units 1. Be familiar with the following sections in the Installation & Operating Instructions manual:  Mechanical Installation Refrigeration (line set size and length) ...
Page 22 GI301 12/03/2012...
Page 23 4. Determine the location of the TXV bulb on the suction line of the A-coil or the line set. Locate a point on top 2-4” from the bulb and towards the compressor. Drill a ¼” hole to accept the equalizer line from the TXV.
Page 24: Mechanical Installation Refrigeration
Mechanical Installation Refrigeration Overview The TTHERM GEO Series split unit includes pre-charged R-410A, with the filter drier factory installed in the unit. The charge may need to be fine tuned based upon line set length and system performance. Line set lengths of over 25ft (7.6 meters) are not recommended due to performance loss and potential oil return issues.
Page 25: Charging Procedure
Line Set Size Information 10 Feet 20 Feet 30 Feet Model Suction Liquid Suction Liquid Suction Liquid TST-024 ¾” ⅜” ¾” ⅜” ¾” ⅜” TST-036 ⅞” ⅜” ⅞” ⅜” ⅞” ⅜” TST-048 ⅞” ⅜” ⅞” ⅜” ⅞” ⅜” TST-060 ⅞” ⅜”...
Page 26: Superheat And Sub-Cooling
Superheat and Sub-Cooling Comments 1. This is a two TXV system – the heating TXV is internal to the main cabinet at the water coil refrigerant entrance and the cooling TXV is located on the plenum air coil at the air coil liquid entrance. 2.
Page 27: Unit Operating Conditions Heat & Cool
Unit Operating Conditions – Heat Discharge Suction Suction Source Blower Discharge Sub cool at Super- heat Model Stage Source temp Δ Air temp Δ Amps 240 pressure at pressure temp at Temp AMPS temp at bulb 68 deg A-RT at bulb bulb 3.3-5.3 26-32...
Page 28 Unit Operating Conditions – Cool Discharge Suction Suction Source Source temp Air temp Δ Blower Discharge Sub-cool at Super-heat Model Stage Amps 240 pressure at 80 pressure at temp at Temp ∆ Dry bulb AMPS temp at bulb deg A-RT bulb bulb 9.4-11.4...
Page 29: R-410A Pressure/Temperature Conversion Chart
Pressure/Temperature Conversion Chart for R-410A PRESSURE TEMP PRESSURE TEMP PRESSURE TEMP PRESSURE TEMP PRESSURE TEMP (PSIG) °F (PSIG) °F (PSIG) °F (PSIG) °F (PSIG) °F 63.5 96.3 120.6 140.0 64.2 96.8 120.9 140.3 11.2 64.8 97.2 121.3 140.6 12.5 65.5 97.7 121.6 140.9...
Page 30: Electrical Hookup
Electrical Installation WARNING DISCONNECT ALL ELECTRICAL POWER BEFORE ELECTRICALLY CONNECTING OR SERVICING THE UNIT. FAILURE TO DISCONNECT THE ELECTRICAL POWER BEFORE WORKING ON THIS PRODUCT CAN CREATE A HAZARD LEADING TO PERSONAL INJURY OR DEATH. Line Voltage The nameplate and/or Installation and Operating Manual specification page provides RLA, LRA, and total amps requirement.
Page 31: Geo Logic Controller
GEO Logic™ Controller GEO Logic Features The GEO Logic controller has a control strategy that will maximize the capabilities of the heat pump. The LED information lights on the front will communicate the THERM GEO’s current stage and mode of operation. GEO Logic also has the capability to communicate diagnostic information so it can be kept running at maximum efficiency.
Page 32: Accessories/Options
NOTE If a programmable thermostat is used, it is recommended that the program be set to disable. In programmable mode, the heating system must be oversized in order to recover from the setback. Since heat pumps are not typically oversized, they require a longer time to recover from the setback period. During this recovery period the system will likely call for electric heat to decrease the recovery time, resulting in lower efficiency.
Page 33 Figure 8 GEO Logic Board Assignment WARNING ANY CHANGES MADE TO SWITCH SETTIINGS, JUMPERS, OR ACCESSORIES CONNECTED TO THE GEO LOGIC CONTROLLER WILL REQUIRE THE GEO LOGIC CONTROLLER TO BE POWER CYCLED FOR THE CHANGES TO TAKE EFFECT. GI301 12/03/2012...
Page 34: Field Setup Overview
Field Setup Overview Thermostat Connect all the standard heat pump connections. This will require 10 conductor thermostat cable. This thermostat wire should be routed through the knockout on the left side of the cabinet by the box containing the GEO Logic controller using the proper strain relief. Terminals are as follows: E –...
Page 35  Tip – when working with the plug-in sensor terminal block and a cable (example, ST), start with black wire. This can help hold the cable when working with the double white and red’s. The sensor has polarity, is sensitive to incorrect voltage, and must be protected from static voltage. Do not cross connect or inadvertently short out sensor wires with power on.
Page 36: Operation Indicators
Operational Indicators Front Panel LEDs: POWER ON (Green LED) ON Solid – Normal Pulsing – Bad sensor 1 blinks every 2 seconds - Bad ST sensor 2 blinks every 2 seconds - Bad DDT sensor 3 blinks every 2 seconds - Bad LWT sensor 4 blinks every 2 seconds - Bad CDT sensor HP STAGE 1 (Bicolor LED) RED - Heating Mode:...
Page 37 EARTH LOOP FLOW/SOURCE WATER LIMIT (Red LED) ON Solid - No source flow lockout Pulsing: Open Loop - LWT < 'Open Loop, Source LWT Warning (Heat)' Closed Loop - LWT < 'Closed Loop, Source LWT Warning (Heat)'. If LWT is less than this value a shutdown with 2 x ACD’s (6 min) is performed This will NOT cause a hard lockout;...
Page 38 Back of Circuit Board – LED’s STG 1-3 (Red LED’s) (not used on TST models) CC (Green LED) ON when the compressor contactor (CC) is ON. ECM STATUS (Green LED) (not used on TST models) ECM RPM (Yellow LED) (not used on TST models) FAULT COUNT (Red LED, left side next to model size dial switch) Normally OFF Counts out a code for the current fault (see Fault Codes)
Page 39 High and Low Pressure Switches – The heat pump is equipped with both high and low pressure switches that shut the unit off if the refrigerant pressure exceeds 550 PSI or goes below 40 PSI. Do not reset a well water system in the heating mode without first verifying water flow.
Page 40: Power On Startup
Power On Startup Before applying power to the heat pump and furnace, check the following items: 1. All plumbing and ductwork to the heat pump and furnace is complete and operational. 2. Low voltage wiring of the thermostat, LMC/INT, furnace/fan coil and any additional control wiring is complete.
Page 41 6. Turn the thermostat to the off position. 7. Place the thermostat in the “COOL” position. Turn the thermostat down to activate a 1 stage call for cooling. The compressor will start after a 3 minute ACD period from its last shutdown. ...
Page 42: Operational Tips
Operational Tips GEO Logic - The GEO Logic board performs the functions controlling the compressor operation, system lockout, compressor anti-short cycle, and a three minute delay after power is applied. Review Operational Indicator section of this manual before proceeding. Pump/Blower Purge – a Y-stat input starts the blower motor, loop source pump, open loop solenoid, and desuperheater pump.
Page 43: Troubleshooting
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.
Page 44 routine continues the heat pump will not be able to maintain the temperature in the house and the backup heat will come on. Possible causes would include: Open Loop Closed Loop 1. Supply water filter that needs cleaning 1. Inadequate source water flow 2.
Page 45 Troubleshooting – General WARNING – Refrigerant Evacuation WHEN REFRIGERANT IS EVACUATED FROM A UNIT WITHOUT ANTIFREEZE IN THE WATER TO REFRIGERANT HEAT EXCHANGERS, WATER IN THE UNPROTECTED HEAT EXCHANGER MUST BE REMOVED OR CONTINUOUSLY FLOWING TO AVOID A POTENTIAL HEAT EXCHANGER FAILURE CAUSED BY FREEZE RUPTURE.
Page 46: Preventive Maintenance
Preventive Maintenance Water Coil Maintenance –In closed loop systems, water coil maintenance is generally not needed. However, if a dirty installation or deterioration of the piping has caused debris to accumulate in the system, the water coil should be cleaned using standard cleaning procedures. For open loop systems installed in areas with a high mineral content, it is best to schedule regular periodic maintenance to inspect and clean the coil if necessary.
Page 47 Troubleshooting – General Troubleshooting Guide for Water-to-Air Geo “Heating” Head Subcool Suction Superheat Compressor Air temp Source temp pressure pressure Amp Draw differential differential Undercharged system High Overcharged system High High High High High High Low air flow High High High High High...
Page 49: Drawing Gr301 - Refrigerant Hookup
Name SPLIT SYSTEM COMP Compressor - HEAT MODE Pressure high limit Pressure low limit Pressure test port SDW-COIL Supplementary heat exchanger TXV-C AIR COIL - COND DW-ST Ref: DW supply DW-RT Ref: DW return Reversing valve DW-RT DW-ST Ball valve SDW- AIR COIL Air heat exchanger...
Page 50: Cooling Mode
Name SPLIT SYSTEM COMP Compressor - COOLING MODE Pressure high limit Pressure low limit Pressure test port SDW-COIL Supplementary heat exchanger TXV-C AIR COIL - EVAP DW-ST Ref: DW supply DW-RT Ref: DW return Reversing valve DW-RT DW-ST Ball valve SDW- AIR COIL Air heat exchanger...
Page 52: Warranty Information - Gx002
TTHERM GEO™ Residential Limited Product Warranty Effective February 1, 2012 TTHERM GEO warrants to the owner, at the original installation site, for a period of three (3) years from date of original purchase, that the product and product parts manufactured by TTHERM GEO are free from manufacturing defects in materials and workmanship, when used under normal conditions and when such product has not been modified or changed in any manner after leaving the manufacturing plant.
Page 53 CONDITIONS AND LIMITATIONS: This warranty is limited to residential, single family dwelling installations only. Any commercial or multi-unit dwelling installations fall under the TTHERM GEO Commercial Limited Product Warranty. TTHERM GEO shall not be liable for performance related issues resulting from improper installation, improper sizing, improper duct or distribution system, or any other installation deficiencies.

This manual is also suitable for:

Tst-024 Tst-036 Tst-048 Tst-060