A multi-zone controller may contain from two to six relays, but the wiring procedure stays consistent. The basic wiring is essentially the same for all multiple zone controllers. There is no need to use the “system pump” terminals, no need to use the “XX” terminals to activate a boiler, and no “priority zone” for an indirect water heater. In other words, the controller is nothing more than three radiant floor zones, activated by three thermostats. The factory installed jumper is not moved.īelow is another example of a multi-zone controller, (i-Link SP-83), but for a very straightforward system. The lines from the power source (circuit panel) are connected to N (common) and L (hot). The circulator pumps are wired to the lower, high voltage terminals for zones 1, 2, 3, etc. In this example, the thermostat connections are made at the upper row of “T”, terminals T1, T2, T3, etc. This feature could prevent someone from “toying” with your thermostats and sending heat to your floor in the summer. If your relay box is wired through a switch, you won’t have to rely on the thermostats alone to shut your system off during the cooling season. It’s also a good idea to wire a standard light switch into the controller circuit so that the entire radiant system can be turned off at one central location. Either that, or a branch from an existing circuit can be run to the controller box. Of course, in all applications, the relay box must be energized by a 110 volt line (see schematic below) from your circuit panel. A row of orange tabs along the top of the controller panel allow you to insert the thermostat wires and a block of terminal screws along the bottom labeled N (neutral) and L (load) make wiring each zone pump very easy. Like the SP-81 above, the multiple zone controllers use the same basic terminal block configuration for the low voltage (thermostat) and the line voltage (running the circulator pumps). Multiple zone systems are generally controlled by a single box containing multiple relays. But, above all, do not connect a 120 vac line to these terminals. The thermostats we sell use batteries, so this feature is not required for the digital display on our thermostats. NOTE: “Power to Thermostat” on the above schematic indicates 24 volts AC coming from the controller to energize a digital display on thermostats that do not use batteries for this purpose.

14/2 Romex electrical wire is recommended to power the Radiant heating system (relay / pump). Pushing back the tab above the terminal block allows easy insertion of the wire. Single zone controller activates a pump when thermostat calls for heat.ġ8/2 thermostat wire from the thermostat in the zone connects to terminals R/W.

Radiant heating thermostats