Generic thermostat help please

my problem which i hope is an easy fix is as follows,

I have 4 temp sensors for different rooms in my house and i’m wanting them to switch on my gas boiler (heating) when the temp drops below a set temp on any of the zones. (over heating room restriction via standard trv)

i am currently doing this with generic thermostat controlling a sonoff relay (device)(which calls for heat) which works, but it seems from monitoring that if say 3 zones where all calling for heat when 1 zone reaches its desired temp it sends a turn off boiler sonoff command. which it does leaving the rest of the house cold until another zone drops below temp sending and on command.

in conclusion i would like the boiler to call for heat if any of the 4 zones are below at target temp. and switch off when all zones are at temp.

many thank

The easiest solution will be using the generic thermostat with the coldest room, that should ensure the other rooms are above the set temperature.

Other way around is making a automation to only turn off each climate component if the other one is above X temperature.