Fire pumps 1

[stintx]

I got a call about a fire pump that was running. When I got there, I checked on/off pressures of the jockey pump and the on pressure of the fire pump. All the settings were good. There were no downstream valves that had been opened. Could it be a clogged sensing line issue on the fire pump or maybe the pressure switch in the fire pump controller going out?

 

[bimr]

You have not posted enough to make a consideration. Some of the switches may fail open.

Was the pump running when you arrived? Someone nay have opened and closed a hydrant.

 

[stintx]

I was told the pump was not running when the engineer showed up. I had asked him about any valves that could have been opened (inspectors test or auxiliary drains)and he told me no. Going off of that, I took his word and checked the on/off pressures which turned out ok.

 

[Pumpsonly]

What type of controller do you have on site? Modern fire pump controller has micro processor based pressure and event recording recordings. Order controller also have a pressure recording chart that will tell you the system pressure condition before the fire pump started.

 

[bimr]

NFPA 20 requires a listed pressure recording device be installed to sense and record the pressure in each fire pump controller pressure-sensing line at the input to the controller. The pressure recorder shall be capable of operating for at least seven days without being reset or rewound.

http://pressure_sensing_line.pdf/

There have been incidents where fluctuations in the water pressure caused accidental starting of a fire pump.

http://www.nasa.gov/offices/oce/llis/0047.html

 

[Artisi]

someone probably washed their car or hosed down the footpath which brought the unit on line.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)