You can install 8 Smart TRVs per room (with a maximum of 32 rooms, up to a limit of 50 Zigbee products in the smart home hub). N.B.: at least one radiator in the property must not be fitted with thermostatic radiator valves and must remain fully open at all times if the system does not include another type of “bypass” (contact an installer if in doubt and to determine the number of radiators affected).