Separate communal and dwelling systems
A heat interface unit, or HIU, transfers heat from a communal system to services within a dwelling. The survey needs to establish which circuit is losing pressure or water and what can be isolated safely.
Provide the heating maintenance contractor’s observations, available schematics and any relevant fault history. Pressure changes alone should not be presented as proof of a hidden leak.
Agree control of the system
- Name the person authorised to isolate or alter the plant.
- Confirm the affected circuit and the areas included in the survey.
- Arrange resident communication if heating or hot water may be interrupted.
- Record who will restore and check the system afterwards.
Confirm specialist competence
Communal heating and HIU work must be within the appointed team’s actual competence and agreed scope. ADI advertises central-heating leak detection. HIU internals and the particular communal circuit still need an agreed scope before booking.
Fire-protection systems, sprinklers and dry risers require their own competent specialists and arrangements. General leak investigation should not be taken as authority to work on them.