Geothermal unit


Unit Placement

For air units, to achieve the greatest efficiency, the heat pump should be centrally located inside the home(in conditioned space). This design provides the utmost in economy and comfort and usually can be accomplished in harmony with the design of the home or within a closet, staircase, or garage in your existing home. A heating system performs most efficiently and can be expected to produce an even warmth throughout the household when it is located properly in the structure and the warm/cool air is transmitted with properly insulated ductwork.

If possible the access panels should remain clear of obstruction for a distance of two feet to facilitate servicing and general maintenance.

Raising the heat pump off the floor a few inches is generally a good practice since this will prevent rusting of the bottom panel of the unit. We recommend that the heat pump be placed on a piece of 2” thick foam pad(included with your unit). The foam pad will smooth out any irregularities in the floor and deaden any compressor noise emitted from the bottom of the cabinet.

AMERICAN DREAM Ultra Performance heat pumps have an air-filter rack which can be installed with the removable end (where the filter is inserted) on either side to facilitate changing the filter.

ELECTRICAL CONNECTIONS

The heat pump has a concentric 1.093” / 0.875” knockout for power supply connection to the electrical box, as well as one for connection to the circulator pump module for ground loop applications. There are two 1/2” openings with plastic grommets (grommet hole is 3/8”) in the upper section of the electrical box, one for the thermostat connections, and one for the optional plenum heater connections.

A schematic diagram and electrical box layout diagram (ELB) can be found inside the electrical box cover of the unit as well as in the Model Specific section of the users manual. The Electrical Tables in the Model Specific section and the ELB diagram contain information about the size of wire for the connections, as well as the recommended breaker size. A properly qualified electrician should be retained to make the connections to the heat pump and associated controls. The connections to the heat pump MUST CONFORM TO LOCAL CODES.

THERMOSTAT REQUIREMENTS

Your unit includes the AMERICAN DREAM  three-stage heating and two stage cooling Geothermal unitthermostat with relay outputs for proper air mode operation. The stages are S1 = heat pump stage 1 , S2 = heat pump stage 2 S3 = electric auxiliary (heating only). One can be purchased with the unit, or other thermostats with the same number of stages can be used.

For water mode operation, a two stage aquastat is required to provide the appropriate control signals. The aquastat can be placed anywhere within the range of the probe cable. The probe should be inserted into a dry well in or near the top of the tank for optimal operation (refer to drawing 000533PDG of users manual). If a dry well is not available, it may be possible to fix the probe to the tank inside the insulation.

INDOOR LOOP CIRCULATOR WIRING

The Indoor Loop circulator provides flow between the heat pump and the buffer tank. The Two Stage Control Box has provisions for connecting the Indoor Circulator so that it will be
turned on whenever the heat pump is in water heat mode and the compressor operates. Connect line voltage (115 or 230VAC) to the terminals marked L1 and L2 of the Indoor Circulator Contactor. Connect the Indoor Loop circulator to the terminals marked P1 and P2. Ensure that the line voltage and circulator voltage rating are the same.

CONTROL BOARD
All heating / cooling units contain a control board that monitors the thermostat signals, safety controls and loop pressures. It controls the operation of the compressor, fan and auxiliary / emergency heat. It also activates the reversing valve and controls the loop sequencing when in cooling mode. Heating only units do not have a control board.
The number of cooling loops must be configured (done at the factory). There are two jumpers to the top right of the micro controller. The configuration is shown in TABLE 8.
There is also a jumper marked DEFAULT that should be left in place. The jumper marked IF NO B TERMINAL should be left place as well unless the thermostat used has a B terminal
that is constantly powered in heating mode.

The control board has 4 connectors: one for the thermostat connections; one for the heat pump component connections; one for the loop solenoid connections; and one for the safety control and loop pressure switch connections. There are also several LEDs to indicate the status of the control board. Refer to drawing 000301CDG for the location of the connectors and LEDs.

The Heart Beat LED flashes once every second. This indicates that the control board is operational. An on-board COP watchdog timer resets the microprocessor should anything affect code execution. The high and low pressure control LEDs flash once per second when a control is open. They will stay on if there is a permanent lockout. The loop switch LED will come on when the loop pressure switch is activated. Note that the loop switch is only for cooling mode, it does not affect heating mode operation.

There is a compressor short-cycle timer (default 2 minutes) and also a mode switch timer (default 5 minutes). Both are adjustable through the control board communications port.