Radio linked Thermostat: Salus RT500RF & RT500ROF

Added by JohnO over 1 year ago

I have been looking at installing a Salus RT500RF thermostat onto my home heating system. The RT500RT has a wireless 2*AA powered 5/7 day thermostat with 5 temperature periods in each day. The thermostat is linked wirelessly to the AC powered boiler control unit which opens & closes a pair of contacts to control demand as you would expect.

The RF link is FSK based using Hope Electronics radios although using different values and radio wafers than typical Jeelabs kit. It is quite straightforward to receive and transmit the RT500RF protocol using Jeelabs kit in this application. The protocol is arguably far too simple for the application since there is very little done to detect data integrity or discourage spoofing.

After purchasing my RT500RF kit I discovered that there is a RT500ROF kit which contains a third component, a wireless temperature setback controller typically used on leaving the home to reduce heating demand when out of the house on an unpredictable basis. Apparently the setback controller uses RF to reduce the thermostat set point by a few degrees.

Does anyone on the forum have access to this setback device as I would like to understand it RF protocol and fake its actions.
The setback device is not available as a separate item from the manufacturers and I am currently reticent to buy a second complete kit to hack it.

Replies (1)

RE: Radio linked Thermostat: Salus RT500RF - Added by JohnO about 1 year ago

I weakened and bought the RT500ROF unit. The protocol is quite different and the temperature measured by the thermostat head is available in the RF transmission. The ROF unit is far superior to the plain RF unit although both wireless protocols are quite primitive.
If anyone has interest in the Salus RT500ROF thermostats I probably have it 90% understood so drop me a line.