Dear Forum Members, In many pump rooms I find a problem of significant vibrations generated by Jockey Pump.
The Pump starts, the pressure rises and the pump stops. The problem is that the period of start-stop is a fraction of a second. In some instances, if the pressure drops slowly, the start-stop is so fast so that the pump does not do the job. If the fire pump starting pressure is close (10psi diff. is suggested by Appendix A of NFPA-20), the Diesel Pump starts. The periodic fast start-stop is not healthy to the motor. I some instances, the start stop generates water hammer (particularly the stop action). It seems that such a small pump is able to cause excessive rise of pressures in systems that are not equipped with "an operating relief valve". This is reflected in damages pressure gauges next to the pump and in a remote system riser. One suggestion is to install a delay relay in the Jockey Pump controller. But this does not solve the knocking when the pump stops. It might be connected with the type of the non-return valve at the pump discharge. I am looking for forum members that share my experience. Thanks Dan _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
