Install Instructions

ManualsBrandsFast-Stat ManualsHeating SuppliesModel 7000 HVAC Wiring Extender

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Model 7000

Installation Instructions

● For air conditioner to heat pump conversions. Extends

the wiring between a thermostat, indoor unit, and

heat pump.

● Provides R, C, G, Y1, Y2, W, and O/B over the 4-wire

thermostat cable, and Y1, Y2, O/B, and W over the

2-wire condenser cable.

● If the thermostat cable does not require more wires,

a Model 9000 can be used to extend only the wiring

from the indoor unit to heat pump.

● This product should only be installed by a qualified

technician.

● Requires a Class 2 transformer providing 23-38VAC.

● The total connected load cannot exceed 2 amps.

● The connected load cannot operate at more than

30VAC (not designed for direct connection to 120VAC

equipment).

● To avoid risk of electrical shock or equipment damage,

disconnect power before beginning installation.

The Sender is the smaller component and is installed inside

the wall behind the thermostat.

The Indoor Unit Module is installed inside the cabinet of

the air handler or furnace. If there is not enough space

inside the cabinet, it may be located in any dry location

without exposure to high temperatures or water.

The Heat Pump Module is installed inside the cabinet of the

heat pump. It is not rated for direct exposure to outdoor

conditions, and should not be installed outside of the heat

pump cabinet.

Note: The Sender will produce a small amount of heat

while operating. Keep the Sender wires as long as possible

to maximize the distance between the Sender and

thermostat. Do not install the Sender in insulated walls.

● If the hole where the thermostat cable wires come

through is not big enough to fit the Sender, enlarge it.

● Place the Sender in the wall and connect the wires

to the sub-base according the wiring diagram (pages

3-4). The Sender will hang by its wires and does not

require any mounting.

● Place the thermostat back on the sub-base.

Overview

Single-Stage Heat Pump

Electrical Safety

Sender Installation

Module Installation

For single-stage heat pumps, connect the Sender’s brown

wire to thermostat ‘Y’ instead of the Sender’s yellow wire.

The Sender’s yellow wire should be taped back as it will

not be used.

The Heat Pump Module’s yellow and brown wires should

both connect to the heat pump’s ‘Y’ terminal.

If the indoor unit’s fan only has one speed, the Indoor Unit

Module’s brown wire should be taped back as it will not

be used.

If the indoor unit requires an O/B connection, the blue wire

from the Indoor Unit Module is used. Otherwise, the blue

wire should be taped back as it will not be used.

There are two installation methods, ‘Grounded Commons’

and ‘Two Transformers’.

Grounded Commons requires a black wire from both

the Indoor Unit Module and Heat Pump Module to be

grounded (page 3).

Two Transformers requires an external 240:24V transformer

to be installed at the location of the heat pump. It does not

require the use of earth ground (page 4).

Single-Stage Fan

Indoor Unit Reversing Valve

Installation Methods

Two Transformer Test

The Two Transformer test ensures that the transformers

in the system are connected in parallel. It is only required

if using the ‘Two Transformer’ wiring method. The

transformer wiring affects the system when the heat pump

is in defrost mode, which should activate the indoor unit’s

heating system.

If the transformers are not in parallel (and are in series

instead), the defrost mode will trip a resettable fuse inside

the Heat Pump Module, and the indoor unit’s heating

system will not start. Reversing the leads on the secondary

side of the heat pump’s 24V transformer will fix the issue.

No damage will occur when the resettable fuse is tripped.

The resettable fuse takes approximately 30 seconds to

reset after being tripped, and must be reset for the defrost

mode to work.

At the Thermostat

At the Heat Pump

1. Set the thermostat so that the heat pump is running in

heating mode. For 2-stage heat pumps the compressor

must be running in high speed.

2. Manually set the heat pump to ‘Defrost Mode’ (see

heat pump manual for instructions)

3. Check if the indoor unit’s heating system is on. If it is,

the test is complete and no further steps are required.

If it is not, proceed to step 4.

4. Switch the secondary leads of the 24V transformer

powering the heat pump and Heat Pump Module.

The transformer lead previously connecting to ‘R’ will

instead connect to ‘C’. The transformer lead previously

connecting to ‘C’ will instead connect to ‘R’.

Summary of content (4 pages)

PAGE 1
Model 7000 Installation Instructions Overview Single-Stage Heat Pump ●● For air conditioner to heat pump conversions. Extends the wiring between a thermostat, indoor unit, and heat pump. ●● Provides R, C, G, Y1, Y2, W, and O/B over the 4-wire thermostat cable, and Y1, Y2, O/B, and W over the 2-wire condenser cable. For single-stage heat pumps, connect the Sender’s brown wire to thermostat ‘Y’ instead of the Sender’s yellow wire. The Sender’s yellow wire should be taped back as it will not be used.
PAGE 2
Fossil Fuel or Supplemental Heat Troubleshooting The Model 7000 supports the use of two modes, ‘Fossil Fuel’ and ‘Supplemental Heat’. The Heat Pump Module has two gray wires which can be connected to a thermostat to operate the optional modes. 1. Remove the thermostat from its sub-base. With a jumper, make a connection between ‘R’ and ‘G’ on the thermostat terminal strip. The fan should activate. Repeat this process for ‘Y1’, ‘Y2’, ‘W’, and ‘O/B’.
PAGE 3
A Grounded Commons Wiring Thermostat Note: The Indoor Unit Module and Heat Pump Module must both have a black wire grounded, otherwise the Heat Pump Module will not receive power. If there is a extra wire in the condenser cable, it can be used to connect the black wire on the Indoor Unit Module and Heat Pump Module together instead of grounding them.
PAGE 4
B Two Transformer Wiring Thermostat Note: After installing the external transformer, follow the ‘Transformer Test’ section to ensure it is in parallel with the indoor unit’s transformer. O/B W Y2 Y1 G R C Black Red Green Yellow Brown White Blue Purple Gray Red Black Note: See the ‘Fossil Fuel or Supplemental Heat’ section for details on the green and purple wire loops and optional thermostat.