Supply water temperature sensor and mixing valve
p. 21
Supply water temperature limit sensor
This feature is not available on the basic master’s version WLM2-1BA and WLM2-3BA
The limit sensor is directly connected to the master at the terminals marked limit sensor. Sensor
type ETF-1899A must be used.
The temperature sensor should be placed on the supply water pipe to the underfloor heating
system, If a limit sensor is installed, without a weather compensation module (WLOC) the master
will control the maximum water temperature. The factory default setting is 55°C, but this value can
be changed via the display.
If a weather compensation module (WLOC) is added to the system, the master will vary the supply
water temperature setting based on the outdoor temperature. A standard compensation curve
has been programmed at the factory. If needed the curve can be changed, see separate USER
MANUAL, MASTER TYPE WLM2.
Mixing valve actuator control
Control of a mixing valve actuator is possible using the digital masters WLM2-1FS and WLM2-3FS
The actuator must be 24Vac powered (max 6VA) and positioned via the 0-10V DC signal, and
should be configured so that it closes the valve if there is no heating demand (0Vdc signal). The
control signal can be reversed to 10-0V via the master menu system if required.
Control action of the mixing valve actuator is P + I and the parameters can be
changed if required in the master menu system.
Please contact the supplier for further instructions.
Fig 11
WLM underfloor heating contr
oller
