It is important to select the correct Type of RCD for the equipment to be used. The Type of RCD will depend on the characteristics of the equipment. Where necessary, equipment manufacturers should specify the RCD Type required. If the information is not available, the manufacturer should be contacted and asked to provide it. It is a legal requirement of UK Product Safety Regulations for manufacturers to provide clear installation instructions to enable safe installation.
https://electrical.theiet.org/wiring-matters/years/2019/77-september-2019/which-rcd-type/
It appears that Worcester Bosch are saying ask the IET and the IET are saying ask Worcester Bosch.
It is important to select the correct Type of RCD for the equipment to be used. The Type of RCD will depend on the characteristics of the equipment. Where necessary, equipment manufacturers should specify the RCD Type required. If the information is not available, the manufacturer should be contacted and asked to provide it. It is a legal requirement of UK Product Safety Regulations for manufacturers to provide clear installation instructions to enable safe installation.
https://electrical.theiet.org/wiring-matters/years/2019/77-september-2019/which-rcd-type/
It appears that Worcester Bosch are saying ask the IET and the IET are saying ask Worcester Bosch.
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