Mystat Jumper Settings

| Jumpers

Jumpers are electronic components used to short two points together to perform a specific operation.

Below is an illustration of what a jumper is and how it is used.

The Mystat hardware of 75F uses a couple of jumpers for various purposes.

| Mystat Jumpers

Position #1

Jumpers at these positions are used to set the mode of operation. 

Switch the jumpers as shown below to enable the W2 Relay.

Switch the jumpers as shown below to enable the Universal 2 Output.

Switch the jumpers as shown below to enable the Y2 Relay.

Switch the jumpers as shown below to enable the Universal 1 Output.

Position #2

At this position, a jumper is used to short the WS or Universal Output 2, and the ON or OFF.

Switch the jumpers as shown below to disable the wiresaver mode.

Switch the jumpers as shown below to enable the wire saver mode.

| Wire Saver Mode

A wire saver module in HVAC systems offers several benefits, primarily by eliminating the need to run a new wire (C-wire) to the thermostat, thus simplifying installation and potentially reducing costs. These modules act as a splitter, allowing 24V systems to function with fewer wires by utilizing existing ones. 

The MyStat, when clubbed with the Wire Saver accessory, intelligently expands a traditional two-relay setup into a three-relay configuration. This allows for the addition of a new control point without the need for running additional wires, offering both flexibility and cost savings in installation.

Mystat V1 Wire Saver

Mystat V2 Wire Saver

Advantages

The following are a few advantages of the Wire Saver mode:

• Reduced Installation Costs: The primary benefit is avoiding the expense and effort of running a new C-wire, especially in older homes where it might be difficult or impossible to do so.
• Simplified Installation: Wire saver modules can make installing a smart thermostat easier, particularly for those without a C-wire connection.
• Compatibility: Many wire saver modules are compatible with various thermostat brands and both heat pump and conventional HVAC systems.
• Enhanced Functionality: Certain modules enable the transmission of multiple signals over a single wire pair, providing additional control features. 

Energy Savings: While not a direct energy-saving feature, the ability to easily install a smart thermostat (which can lead to energy savings through optimised heating and cooling) is facilitated by the wire saver. 

Note: This feature requires the controller to be powered with a 24V AC supply. The system will not support this functionality on alternate power inputs.