Can a larger RPZ be installed on a smaller pipe?

[jbarnes]

This is probably moronic, but...I need to install an RPZ on a 2-inch water line, but the units that are approved, can be installed in the vertical position and will FIT w/o major repiping are all 3-inch or larger.

The pressure to this line is 90-100 psi and the demand is not high since it only serves a few eye baths and safety showers.
Thanks, jb

 

[unclesyd]

Can you use a 2" RPZ like used on potable water of which I assume that your water is?

 

[jbarnes]

It is potable water and I can use a 2-inch RPZ, but the ones that are approved by the DOH in that size are a configuration that would require modifications to the existing piping. This RPZ is being installed on an existing line and space is limited. The 3-inch unit would fit better and require less reconfiguration of the piping. There is not an approved 2-inch unit of the same configuration of the 3-inch unit.

 

[stanier]

An RPZ is only a dual check valve with samplng between. If here is sufficent head to close the valve the size is irrelevant.

Geoffrey D Stone FIMechE C.Eng;FIEust CP Eng

http://www.waterhammer.bigblog.com.au