Page 1 of 4 Specifications subject to change without notice Nordic Technology Ltd www.fast-stat.com
Application
The FAST-STAT Model 3000 is designed to add additional control
wiring between the thermostat and indoor unit or between the
indoor unit and outdoor unit.
Before Installing This Product
1. Read Instructions. If you have any questions please contact
our tech support line
2. This product is designed for use only on 24-volt AC circuits
supplied by a Class 2 transformer.
3. This product is only to be installed by qualified technicians.
4. To avoid risk of electrical shock or equipment damage,
disconnect power before beginning installation.
Sender Installation
When used to add wiring between the thermostat and indoor
unit, the sender is installed in the wall space behind the
thermostat. Enlarge the opening around the thermostat cable so
that the sender can be inserted into the wall cavity. Once the
connections to the cable and thermostat are completed, insert
the sender into the wall cavity. The sender hangs by its leads and
does not require any mounting.
When used to extend wiring between the indoor and outdoor
units, the sender is connected to the indoor unit terminal strip
or leads. It then hangs from the terminal strip or is grouped
together with the other leads.
Receiver Installation
The receiver module is normally mounted inside the cabinet of
the indoor or outdoor unit near the other controls. If there is no
space inside the cabinet, the module may be located in any dry
location without exposure to high temperatures or water.
Wiring
1. See included Wiring Diagrams for your application.
2. The power supply must be between 20 to 30 volts for
proper operation. The total connected load must not
exceed 2 amps. The connected load cannot operate at a
voltage of more than 30 volts (not intended for line voltage
control).
Sequence of Operation
The receiver has 3 normally-open relays, one each for the
yellow, green & white wires. One side of each relay contact is
connected to a red wire which is then connected to the
transformer “R” terminal. When any relay is energized, it will
connect its load to the transformer “R” terminal.
A 24 volt input on the sender white
wire will cause a 24 volt output on the
receiver white wire. A 24 volt input on
the sender green wire will cause a 24
volt output on the receiver green
wire. A 24 volt input on the sender
yellow wire will cause a 24 volt output
on both the receiver green & yellow
wires.
Troubleshooting –not operating
1. Check that there is 24 volts between the receiver red and
black wires.
2. Check that the sender purple and receiver purple wires are
connected together (and not crossed). If they are crossed,
then a call for heating will provide cooling and a call for fan
or cooling will provide heat.
3. At the receiver, join the receiver purple and red (red wire
going to the sender) wires together. All 3 relays in the
receiver should energize and switch on their connected
loads. If the connected loads do not start, then measure the
voltage from the receiver green, yellow & white wires to the
transformer common. There should be a reading of 24 volts
AC at each wire. If there is voltage at the yellow, green &
white wires but the loads do not start, then check the wiring
of the connected loads. If the receiver relays cannot be made
to energize by this test, then the receiver may be defective.
4. If test #3 works OK but it doesn’t operate when connected to
the sender then join together the 2 wires from the cable that
are connected to the sender red & purple wires. This should
cause a 24 volt output on the receiver green, yellow & white
wires (same as test #3). If the receiver relays do not energize
during this test, then there is a problem with the cable that
connects the receiver and the sender together.
5. If test #4 works OK but it doesn’t operate when connected to
the sender, then jumper transformer power “R” (sender red
wire) to the sender green, yellow & white wires (one at a
time). This should cause the loads connected to the receiver
green, yellow & white wires to start. If this test fails, then the
sender may be defective. If this test works then the FAST-
STAT and the field wiring is OK. The problem may be a
compatibility issue with the thermostat.
Troubleshooting –2 stage compressor
In some installations the indoor unit fan may operate in high
speed when the outdoor unit is running in low speed. This is
caused by the sender having a 12 volt DC voltage on the indoor
unit Y2 terminal. Some furnaces or air handlers mistake this 12
volts DC for 24 volts AC and switch the fan into high speed. To
correct this if it occurs add an isolation relay as follows:
Tech Support Line: 1-800-775-4750 ext. 3
Monday –Friday: 8:30am to 4:30pm (Pacific Standard Time)
FAST-STAT Model 3000 Installation Instructions
Purple Yellow
White
Sender
C
R
Y1 Y2
Relay
coil
