Service piping vs. Mechanical System piping

[Yankee]

2009 IECC

Sections 403.3 and 403.4 one type of piping has to have R3 and one has to have R2. I am not clear on what the difference is between these piping systems, as it seems that some mechanical piping is carring service water (as opposed to . . . other fluids).

Any thoughts?

 

[Dr. J]

Definition: SERVICE WATER HEATING. Supply of hot water for purposes other than comfort heating. This is intended to be domestic hot water (the stuff that comes out of a faucet - "domestic" isn't all that descriptive either). Unfortunately, this is ambiguous, and could mean things like snowmelt, or pool piping.

Thus hydronic heating piping to base board and underfloor radiant needs to be min R-3, while circulating domestic hot water, snow melt, and pool piping is min R-2.

 

[Yankee]

Ok, thanks, , I found a definition for service water, but didn't see the "service water heating".

Seriously, there probably really isn't much difference between r2 and r3, maybe they should just pick one number for both.

 

[peach]

service is usually the public, potable water service to the building.. mechanical service piping is generally self contained (process water or other fluids).