| Question: 11-04 | Code Section: 7 | Date: 28 February 2011 | OBC 2006 Reference: 7.6.1.16.; 7.6.2.2.; 7.6.3.3. |
Question Submitted: 7.6.1.16. Could the committee provide various methods of acceptable protection against
thermal expansion.
Interpretation: 7.6.1.16.(1) Protection against thermal expansion shall be required when a check valve is
required by Article 7.6.1.10., a backflow preventer is required by Article 7.6.2.2., or a pressure
reducing valve is required by Article 7.6.3.3.
Suitable protection can be achieved by;
a) the installation of an adequately sized diaphragm expansion tank designed for use
within a potable water system,
b) the installation of a thermal expansion relief valve conforming to CAN/CSA-B125.3 (ie.
the only approved T.E.R. Valve presently is used as a shut off valve on the cold supply
to a hot water tank and must be set to a pressure of 550 kPa or less and designed for
repeated use).