Plant, boiler and incinerator rooms

Interested in views on where the line should be drawn between ‘local water heating appliances’ and boilers - the terms used in C/AS2 4.10.3. We are increasingly seeing continuous hot water units (ie. Infinity) being used to replace traditional large water storage boilers in existing plant rooms which don’t already meet the requirements of this clause in terms of fire rating etc. This obviously comes up in new builds also.

In some situations there may only be one unit, but in some cases there will be a number of individual califonts on a manifold supplying hot water for central heating or a larger number of plumbing fixtures throughout a building. This has become more difficult to interpret consistently.

I would like to know how others are dealing with this. Thanks.

I have previously interpreted “local” to mean serving one household unit or similar. I wouldn’t consider a water heater that serves a multi residential apartment building to be “local”.

Some years ago, I investigated the risk of boiler rooms using the IGEM risk guide for gas plant. Fire rating the room or distance from buildings was a base requirement for an acceptable level of risk as a minimum, along with ventilation etc. On that basis, The room should be fire rated unless it is only serving the unit it is used for.

I could not track down a reason why certain requirements (such as external access ) were a requirement. It appeared to be “it has always been requirement”. Overseas jurisdictions and the IGEM guide when you ran the numbers allowed basement plant rooms with restrictions, such as needing gas detectors, type of gas (heavier or lighter than air), type of plant, mechanical interlocks, flame out detectors etc

Thanks for taking the time to respond Geoff. I do remember your ‘Bomb in the basement’ presentation at FireNZ some years back. Your interpretation is very similar to the position I have taken previously.