Features
Setting Up the System
Each thermostat can be selected to operate a specific output which controls the thermal actuators on the manifold. The Master controller has 6 outputs, and additional Slave modules can be added to make up a maximum of 14 switching outputs.
On the thermostat, the number of the output (its CH channel) is set with a screwdriver. Up to 14 channels can be set on the switch which is included in each thermostat, and there are two auxiliary channels (see later).
A thermostat set for CH1 will activate the actuator connected to output 1 on the master. If two thermostats are placed in the same room and set on the same channel, the temperature control will work according to the average temperature of both thermostats.

Setting the Thermostat Operating Mode
Thermostats type WLTM-19 and WLTD-19 have a slide switch for selecting the mode of operation of the thermostat. Four different modes can be selected: Auto, Day, Night and OFF.

• Auto: The thermostat will follow the temperature settings of the master, or if the thermostat belongs to a zone group using a WLCT clock thermostat, it will follow the automatic sequence of temperatures and timings set in the WLCT.
• Day: It will control the room temperature according to the DAY setting defined in the master (typically 20°C).
• Night: It will control the room temperature according to the NIGHT setting defined in the master (typically 15°C).
• OFF: It will control the room temperature according to the OFF setting defined in the master (typically 5°C). This setting is intended to be a “frost protection” mode and is used if the room is to be left unoccupied for long periods.

WLTM-19 & WLTD-19 are recommended for guest rooms and other infrequently used rooms, as they allow simple override of the automatic timing sequence.

Setting of Room Temperature
Centrally, in the master, are default temperature settings that are valid for all non clock thermostats that are connected to the system. In Master WLM 1BA, the DAY temperature setting is fixed at 20°C and the NIGHT temperature is fixed at 15°C.
In Master WLM 1FS, the DAY and NIGHT default temperatures are adjustable.
Automatic switching between DAY and NIGHT temperatures is done by either connecting a separate timing device to the master, or using a WLCT clock thermostat and allocating other non clock thermostats as part of its group. It is possible to have two or more clock thermostats in the system, with each one having its own group of non clock thermostats.
The WLTA, WLTM, or WLTD thermostat is locally adjustable with its own adjustment knob. With this knob the temperature setting from the Master can be increased or decreased by 4°C for that specific room. If the WLTM-19 or WLTD-19 thermostat has been allocated to a clock controlled group, then when AUTOMATIC mode has been chosen, the temperature settings will be as programmed in the clock thermostat and not in the master, but the same local +/-4°C adjustment is available.
On the Master WLM 1FS, if the temperature setting is changed, then the default temperature for all the rooms is changed, and the local adjustment then increases or decreases this new setting by +/- 4°C.

Channel 15 Party and Vacation Function
If any thermostat type WLTM-19 is set to CH 15 it will not operate a single output channel, but instead it will override the whole system. Thus if it is set to the OFF mode, the whole system will then operate only to provide frost protection of the property. Similarly, it can also be set to DAY position to override any automatic timing sequence programmed into the system.

Limit Sensor
Thermostats with limit sensor (WLTD-19) are used to maintain a minimum temperature in a heated floor system, for example, to keep tiles in bathrooms and kitchens warm in spring and autumn when there may be little demand for room heating, or to act as a maximum limitation to avoid damaging wooden floors or other floor surfaces, if demanded by the manufacturers.
Thermostats with a limit sensor have a mechanical switch on the printed circuit board allowing it to be set for MIN. or MAX. temperature regulation. If set for MAX., it will have a temperature setting of 27°C. Set for MIN., it has a setting of 17°C.
If the thermostat has been allocated to a zone group controlled by a WLCT clock thermostat, the limit settings can be changed by accessing the clock thermostat. The limits then set will apply to all relevant limit thermostats belonging to that group.

Master with Graphical Display
The master type WLM-1FS and WLM-3FS have a graphic display that is backlit. For easy operation it uses a simple and easy to understand system of icons. Values are easily changed using the arrow up/down and confirm button.
The master also contains a full information menu that can be used when servicing the heating installation.

Exercise of Valves
In order to avoid pumps & valves seizing due to inactivity, the thermo actuators, pumps and the mixing valve are exercised each 3rd day. Any item that has been used during the previous 3 days is excluded from the exercise. The demand relay for the boiler will not be activated.

Pump Control
Each master has two different pump outputs, one to control the primary pump and the other for the secondary pump. The IO (Slave) module only controls a secondary pump. The relay output for pump control will be energised after a delay of 3 minutes when any connected room thermostat calls for heat. A 230V AC pump (max 4A) can be directly connected to the master. When the signal is turned off the pump will remain running for 1 minute to circulate any residual heat entering the system. A built-in delay action creates a 5 minute pause between OFF/ON actions to prevent short cycling of the pumps and boiler.