as is widely known in a gas boiler in the simplest case, a jumper is installed instead of a thermostat relay and the boiler operates depending on the water temperature sensor in the system
the gas boiler located outside area which supported by Bosch Siemens etc and would like to avoid uncontrolled servers
this why HA + CloudFlare soution seems the best
the question
looking for solution - buy + install - a HA EtherNet RJ-45 relay (dry contact will advantage to avoid contactor + PoE too to avoid additional socket) which can simply installed
as you can see it is a lot free space inside the boiler control box so relay can be install easily
the idea is to use a relay Normally Closed contacts
if something goes wrong in the HA app, it is assumed that the relay NC contacts will be closed and the boiler will work
if everything is in order in the Smart Home system and the temperature is above +15 C, then the relay NC contacts will open according to the HA scenario and the boiler will not work
all this is done in case of a long absence of more than 4 months
if there are any better solutions about which I simply could not get and read, I will be grateful for advice on where to look
the technician who will mount can assemble the simplest circuits but will not be able to program
HA management should be simplest as possible
solutions based on ZigBee or WiFi are understandable, but I want to avoid and stretch EtherNet RJ-45 cable to the gas boiler
perhaps someone has already done this solution or wants to do it
thanks in advance for any suggestions or ideas on the topic