Deluge valves

[cbf399]

Hi,

I was called to repair an air compressor that is used to supply pressure to the dry side of an old Grinnell deluge valve.

I noticed that the in-line regulator going to the valve was bypassed, and that the pressure on the dry side of the valve was 38psig.

The pressure at the air compressor was 80psig.

Shouldn't the pressure be the same on the dry side of the valve as at the compressor?

Any ideas as to why the pressure drop?

 

[gouveia]

The "air maintenance" device used on dry valves typically has a bypass valve around the in-line pressure regulator. However, this valve is normally closed.

I am not sure if that answers your question. On the plus side, it sounds like the pressure regulator is operating correctly and the 38 psi sounds appropriate for a dry valve with 100 psi of static water pressure.

 

[apayams]

Hello Every one ,
in a stanpipe system , where we put cabinets,
how do we figure out the outlet sizes on stand pipe (for valves)?

 

[TravisMack]

Apayams:

The local building codes indicate where/when to install building standpipes. The standpipes are typically located at each exit stairwell. Depending on the local fire officials requirement, the cabinets can face into the stair, or into the corridor. Again, the building code dictates if you need a Class I, II or III standpipe. The hose valves will either be 2½" or 1½" depending on the required standpipe classification.

Again, grab a copy of the local building code and reference somewhere around section 900 for the standpipe requirements.