Item Description
Differential thermostat for home solar hot water system
1. Feeding voltage - 12V DC
2. Temperature range: from 1 0C to 90 oC
3. Differential range form - 0.3 to 37C - set with trimmer.
4. Relay Output : 10А/125V DC
10A/250V AC
10A/12V DC
5. Sensors - not waterproof.
Plate dimensions - 45 x 25 mm.
Length of wires on probes - 25 cm, can be extended up to 15 m.
Led indication for working load.
Method of work - Whenever the Probe 2 is measured to be hotter than the Probe 1, the output NO contact of the relay close and led come on. The output remains on, until the measured temperature difference between the two sensors has fallen depending of the set differential by the trimmer.
Setting differential temperature:
The trimmer need to be at average position initially. Rotate it at left and right precisely until led go off.
In this way thermostat is set at the lowest differential temperature and is ready for work.
When you rotate it counterclockwise - increase differential temperature.
Please note: trimmer is not so precise and small rotating make big change of the temperature between two sensors.
For example - Probe 1 can be located at the output pipe of hot water boiler and Probe 2 - to Output pipe of the solar panel. The output NO contact can be used to drive 12V or 220V up to 10A water pump.
In this way - when solar panel is hotter than boiler - the pump will come on.
When Differential temperature of the two probe come equal to the set by trimmer - the relay will be deactivated.
