Weekly Fire Pump Churn & Automatic Pressure Switch Cut-In Test

1. Purpose & Scope

Executing NFPA 25 & NBC Part 4 weekly inspection, testing, and maintenance (ITM) protocol for main electric, diesel backup, and jockey fire pumps.

2. Sequential Execution Steps

1. Notify Security & BMS Control Room: Place fire alarm monitoring station in TEST mode to prevent false municipal fire brigade dispatch during hydro-pressure drops.
2. Verify Header Pressure & Jockey Pump Cycling: Observe fire header pressure gauge (typically 7.0 – 10.0 bar / 100 – 145 PSI). Slowly open test drain valve to drop pressure. Confirm jockey pump starts automatically at cut-in pressure (e.g. 7.5 bar) and stops at cut-out pressure (8.5 bar).
3. Initiate Main Electric Fire Pump Manual Run (Churn Test): Press START on main electric pump controller. Run pump for 10 minutes at zero flow (churn). Verify casing relief valve discharges a steady stream of cold water to prevent impeller casing overheating.
4. Test Automatic Diesel Fire Pump Cut-In: Isolate main electric pump power. Open inspector test valve to drop header pressure below electric cut-in to diesel cut-in threshold (e.g. 6.0 bar). Confirm diesel engine cranks and starts within 15 seconds. Run diesel pump for 30 minutes.
5. Verify Packing Gland Leakage: Check pump stuffing box packing gland. It must drip 10 – 20 drops per minute of water to lubricate and cool the Teflon/graphite packing rings. Tighten gland nuts slightly if leakage exceeds 60 drops/min.
6. Restore All Valves to Normally Open (Locked): Close test drain valves. Verify all suction and discharge OS&Y gate valves and butterfly valves are fully open and chained/supervised with tamper switches. Reset fire alarm panel.