IECC 2012 as applied to existing infrastructure

[lukaiENG]

Hi,
I wanted to get other opinions on economizer requirements for a project we're looking at.
The existing building has a large existing chilled water system which has been used to serve both the existing AHUs etc for the general office areas as well as an old data center within the building. The building is basically mothballed currently.
A lot of the equipment is in pretty good order and can be put back into service, the system currently has no economizer.
My initial thoughts were that we would have to provide an economizer on the system to comply with IECC 2012, however when I considered it further I realized that we would not be adding any heat rejection capacity, therefore the requirement was a little less clear.
excerpt from IECC 2012:
C101.4.3 Additions, alterations, renovations or repairs.
Additions, alterations, renovations or repairs to an existing building, building system or portion thereof shall conform to the provisions of this code as they relate to new construction without requiring the unaltered portion(s) of the existing building or building system to comply with this code. Additions, alterations, renovations or repairs shall not create an unsafe or hazardous condition or overload existing building systems. An addition shall be deemed to comply with this code if the addition alone complies or if the existing building and addition comply with this code as a single building.

How I read this is that as long as we are not altering the heat rejection part of the system we do not have to comply with the code requirements for it.

It's still a little grey, as while we are not altering capacity components on the heat rejection system, we are adding some additional valves for system resilience.

Any opinions? I'm currently of the view that we don't need to add the economizer

 

[lukaiENG]

bump

 

[dbill74]

When it comes to renovations, there is generally a monetary threshold at which point all systems in a building are required to be brought to current code requirements. Typically 50% total building cost. You need to read the rest of the code for this.

My next question would be is the economizer Life Cycle Cost effective? There are parts of the world where economizers would be utilized so little as to not be worth installing.