NFPA Fire Pump Group
NFPA 20–oriented fire pump packages for stationary fire protection — electric or diesel drive, with jockey pump, controllers and project accessories.
What is NFPA?
The National Fire Protection Association (NFPA), founded in 1896 in the United States, is widely accepted worldwide for its publications, programs and standards on fire and occupational safety. Training based on these standards improves practical application on projects.
What is NFPA 20?
NFPA 20 (Standard for the Installation of Centrifugal Fire Pumps) defines specifications, performance and installation rules for fire pumps, pump sets, motor control systems and the ancillary components that must be used.
Desan Engineering supplies fire pump groups manufactured in line with NFPA 20–oriented requirements for stationary fire protection systems.
Highlights
- Separate controller for each pump
- Shut-off pressure not exceeding 1.4× rated pressure
- At 1.5× rated flow, pressure not less than 0.65× rated pressure
- Suction pipe velocities below 4.57 m/s (15 ft/s)
- Bearings with minimum 5,000-hour service life
- Bronze impeller; shaft AISI 316 or AISI 304; casing GG-25 cast iron
- Sealing with five-ring soft packing in series production
- Electric motor service factor not exceeding 1.15
- Flanges to DIN 2533 / PN 16 (suction & discharge typically TS EN 1092-2 / PN 16 on TNSP platforms)
TNSP-based fire pump set
Fire groups are commonly built on TNSP horizontal end-suction centrifugal hydraulics: single-stage, volute casing, closed impeller, coupling drive between motor and pump shaft. Soft packing is standard; mechanical seal can be supplied on request. Back-pull-out style access allows seal, shaft, bearings and impeller service without removing the volute from the piping. Rotation is counter-clockwise from the suction side; bearing housing is externally lubricated with an oil sight glass.
Electric motor driven fire pump sets
For maintenance, it is important that the pump can be serviced without full system dismantling. A jockey (leak) pump handles minor system leaks before the main pump starts, avoiding unnecessary main-pump cycles. Where mains power fails and a generator does not start, a diesel-driven fire pump can back up the electric set. Pressure switches support backup sequencing between units. Gate valves are preferred on the suction line; vacuum and pressure gauges monitor suction and discharge. Cooling-related valves on the set are kept closed in normal fire-pump duty. Multi-pump arrangements are typically designed for 100% redundancy so another unit can take over on failure. The fire suppression installation should resist horizontal seismic loads up to 0.5× its weight.
Diesel engine driven fire pump sets
In fire prevention systems, pumps are often used with 100% redundancy, and many sets are diesel-engine driven. NFPA 20 determines when an engine-driven pump is required. For electric pumps, relief-valve setting at shut-off is typically 1.21× shut-off head, with the valve on the discharge side. Desan Engineering uses spring-loaded relief valves in fire suppression packages.
| Parameter | Value |
|---|---|
| Standard focus | NFPA 20 — centrifugal fire pumps |
| Rated flow range (typical) | 100–5,000 gpm (up to ~8,000 gpm per catalog range notes) |
| Rated pressure (horizontal) | Approx. 30–262 psi |
| Rated pressure (vertical) | Approx. 26–510 psi |
| End-suction fire pumps | Approx. 50–1,250 gpm standardized flows |
| In-line fire pumps | Approx. 50–750 gpm |
| Vertical turbine fire pumps | Approx. 250–5,000 gpm |
| Hydraulics platform | TNSP horizontal end-suction centrifugal (typical) |
| Impeller / shaft / casing | Bronze / AISI 316 or 304 / GG-25 |
| Sealing | Five-ring soft packing (mechanical seal on request) |
| Flanges | DIN 2533 – PN 16 / TS EN 1092-2 PN 16 |
| Electric motor SF | ≤ 1.15 |
| Drivers | Electric motor and/or diesel engine |
| Accessories | Controller per pump, jockey pump, gauges, valves, relief valve |
System notes
- Jockey pump for minor leaks before main pump start
- Pressure switch for backup / sequencing between units
- Gate valves preferred on suction; vacuum gauge (suction) and manometer (discharge)
- Multi-pump layouts for 100% redundancy
- Seismic resistance target: horizontal loads up to 0.5× system weight
Fire group package reference layout.
Fire group construction / arrangement reference.
Fire pump characteristic curves (NFPA 20)
Rated duty points follow NFPA 20 characteristic rules:
- Shut-off (Hmax) — pressure at zero flow shall not exceed 140% of rated pressure
- Rated point — rated flow Q and rated head Hm
- 150% of rated flow — pressure shall not fall below 65% of rated pressure
According to NFPA 20, published rated flow rates for fire pumps must match the standardized flow steps used in fire protection design (selection is project-specific within those steps).
What to send for selection
- Required flow (gpm or m³/h) and pressure / head
- Electric and/or diesel driver preference
- Number of main pumps + jockey requirement
- Controller, valve and instrumentation scope
- Site power / fuel and redundancy concept
Share duty data via WhatsApp or the Request Form tab for a package proposal.
Send your project requirements. Our team will reply with the suitable pump selection.
