YONGFAN HVAC - Premium Header
Engineered HVAC & Industrial Air Systems
YONGFAN HVACYOFAN HVAC Home
VFD Water Supply Equipment | JFHB | YONGFAN
Constant-Pressure Booster · JFHB Series · 8–5,500 m³/h

VFD Water Supply Equipment: Matched to Peak Demand & Low-Flow Sleep

VFD water supply equipment must match peak demand, required pressure, pump staging and inlet conditions; a poorly selected booster can waste energy or cycle excessively at low flow.

YONGFAN JFHB Fully Automatic Constant-Pressure VFD Water Supply Equipment combines pressure feedback, variable-speed pump staging (up to 8 pumps), ≤0.01 MPa accuracy, and an integrated buffer tank (Φ600–Φ800 mm) for zero-demand pump sleep.

Flow Capacity 8 – 5,500 m³/h
Head Span 20 – 250 m
Regulation ≤0.01 MPa Accuracy
Buffer Tank Φ600 – Φ800 mm
YONGFAN constant-pressure VFD water supply equipment
Automated Constant-Pressure Booster LG Vertical Multistage Pumps · PID Variable Speed · Integrated Buffer Hold
01 / Hydraulic Analysis

Booster Failures Appear When Peak & Low-Flow Operation Are Treated as One Duty

A building booster can meet the morning peak and still operate terribly for the remaining 20 hours if large pumps continue running simply to hold network pressure during minimal overnight draw.
YONGFAN non-negative-pressure water supply equipment
Staged Pumping Strategy

Why Variable Speed Needs a Low-Demand Strategy

Per U.S. DOE Pump Systems guidance, matching pump capacity to dynamic system demand and stopping pumps during zero-draw saves energy and prevents mechanical wear.

Oversizing Active Pump Group

Selecting one large pump for peak morning draw forces it to run at deep low-frequency turndown overnight, wasting energy and overheating pump casing.

Impact: Excessive power consumption & seal wear

No Zero-Demand Sleep Strategy

VFDs slow pumps down, but without an integrated buffer tank to hold pressure, pumps cannot sleep during zero demand without pressure dropping.

Impact: Constant idle running & hydraulic heating

Break-Tank vs. Direct Municipal

JFHB is engineered for break-tank or atmospheric storage suction. For direct municipal boosting without break tanks, select JFWZ Non-Negative-Pressure equipment.

Impact: Suction pressure loss or cavitation

Head from Floor Count Alone

Booster head must include suction water level, pipe/valve friction losses, and required fixture residual pressure (e.g. 0.1–0.2 MPa), not just elevation.

Impact: Inadequate pressure at upper fixtures

Five Parameters Controlling JFHB Selection

Sizing connects peak demand flow, suction water head, required discharge pressure, and pump staging.

01 Design Peak Flow (m³/h)
02 Required Total Head (20–250 m)
03 Multi-Pump Staging (2W+1S Std)
04 Buffer Hold Tank (Φ600–800 mm)
02 / Model Portfolio

JFHB Series Model Selections: Standard Booster Combinations

Representative standard vertical multistage (LG) and inline (ISG) configurations. Custom engineered skids extend to 5,500 m³/h.
Model Rated Flow (m³/h) Rated Head (m) Outlet DN Pump Family Motor Power Buffer Tank
JFHB8-20-2-600L 8 20 DN32 ISG Inline 0.75 kW Φ600 mm
JFHB12-30-2-600L 12 30 DN50 LG Vertical Multistage 1.5 kW Φ600 mm
JFHB12-120-2-600L 12 120 DN50 LG Vertical Multistage 5.5 kW Φ600 mm
JFHB22-30-2-600L 22 30 DN80 LG Vertical Multistage 2.2 kW Φ600 mm
JFHB22-120-2-600L 22 120 DN80 LG Vertical Multistage 7.5 kW Φ600 mm
JFHB45-40-2-600L 45 40 DN100 LG Vertical Multistage 5.5 kW Φ600 mm
JFHB65-100-2-600L 65 100 DN125 LG Vertical Multistage 18.5 kW Φ600 mm
JFHB90-120-2-600L 90 120 DN150 LG Vertical Multistage 30.0 kW Φ600 mm

*Wider custom skids cover up to 5,500 m³/h, 250 m head, and 315 kW with up to 8 pumps in parallel cascaded control.

03 / Booster Control

The Buffer Tank & Cascaded Pump Staging

How JFHB balances active modulation, automatic pump sequencing, and low-demand pressure hold.

Active Demand Modulation

The discharge pressure transmitter feeds measured pressure to the PLC. A PID loop modulates VFD frequency to maintain setpoint accuracy within ≤0.01 MPa across shifting fixture draw.

Cascaded Multi-Pump Staging

As demand exceeds single-pump capacity, auxiliary pumps start in stages. Lead pump continues VFD modulation to trim flow. Programmable rotation balances running hours across all pumps.

Zero-Demand Buffer Sleep

During zero consumption, the pre-pressurized buffer tank absorbs small leakage and holds line pressure. When pressure stays within band, all pumps shut down until pressure falls below cut-in threshold.

04 / Procurement Protocol

Information Required for Accurate JFHB Sizing

Provide calculated fixture units / design peak flow, suction water level, required outlet pressure, and building pressure zones.
STEP 01

Peak Demand Flow

Probabilistic peak flow (m³/h) from plumbing fixtures or process equipment.

STEP 02

Suction & Delivery Head

Suction tank water level and required pressure at the highest/remotest fixture.

STEP 03

Pump Redundancy

Number of working pumps and standby philosophy (e.g. 2W+1S or 3W+1S).

STEP 04

Control & BMS Protocol

Modbus RTU standard, BACnet IP gateway, cabinet IP rating, and alarm contacts.

Engineering Handoff

Submit Project Parameters for JFHB Booster Sizing

YONGFAN application engineers will calculate pump staging curves, select buffer tank volume, and provide complete GA drawings.

Peak Flow Rate (m³/h)
Required Total Head (20–250 m)
Suction Source: Break Tank Water Level
Pressure Class: 0.6 / 1.0 / 1.6 MPa
Pump Staging: 2W+1S / 3W+1S / Custom
BMS Protocol: Modbus RTU / BACnet
05 / Manufacturing Quality

Pumps, Controls & Buffer-Hold Testing

Fabricated on channel-steel skids with anti-vibration pads and fully validated on a calibrated factory test loop.
Pumps QA

Certified Multistage Pumps

LG vertical multistage and ISG pumps verified with factory hydrostatic certificates and performance curves.

VFD QA

PID Loop Calibration

Pressure regulation accuracy verified at ±0.01 MPa with calibrated reference transmitters and soft-start ramps.

Sequence QA

Buffer Sleep Verification

Factory sequence tests verify cascaded pump staging, pump rotation, dry-run cut-off, and low-flow buffer sleep.

Electrical QA

IP54/IP65 Cabinets

Control panels undergo hi-pot insulation checks, ground continuity tests, and manual bypass mode checks.

Lead Time: 20–35 working days standard; 35–50 days for motors >100 kW or 1.6 MPa skids. Trade Terms: EXW, FOB, CIF, CFR, and DDP export logistics supported globally.
06 / Engineering Knowledge

VFD Water Supply Equipment FAQ

Direct engineering answers regarding JFHB flow range, buffer tank function, BMS integration, and municipal boosting.

What is the documented JFHB range?

YONGFAN states an overall range of 8–5,500 m³/h, 20–250 m head, and 0.55–315 kW motor power across standard and custom skids.

What does the buffer tank do?

The JFHB buffer tank holds pressurized water during low or zero demand so the main pumps can stop until network pressure falls below the restart setpoint.

How many pumps can be controlled?

The control architecture supports cascaded sequencing of up to 8 pumps in parallel with programmable lead-pump rotation.

What pressure accuracy is documented?

YONGFAN achieves ≤0.01 MPa pressure-regulation accuracy and verifies the control loop on a calibrated factory test rig.

Does JFHB support BMS integration?

Yes. RS-485 / Modbus RTU is standard. BACnet MS/TP and BACnet/IP gateways are available on request.

Should I use JFHB for direct municipal boosting?

Not when direct connection to public mains is required. Use Non-Negative-Pressure Water Supply (JFWZ) when local regulations permit direct boosting.

07 / Application Boundaries

JFHB Engineering Boundaries

Key engineering rules for booster pumps in domestic and process water systems.
Boundary 01 / Pressure Zoning

Zone High-Rises

Do not use a single booster for tall buildings without dividing lower zones with pressure-reducing valves or separate sets.

Boundary 02 / Low-Flow Sizing

Staging Required

Do not select one large pump for peak demand without verifying the normal overnight low-demand operating point.

Boundary 03 / Suction Source

Break-Tank Suction

JFHB requires an acceptable positive suction source (such as a break tank) and does not include municipal inlet protection.

Boundary 04 / Surge Analysis

Not Surge Protection

The buffer tank provides local pressure-hold and damping, not complete water-hammer protection for long cross-country mains.

08 / Engineering Handoff

Select the Right JFHB VFD Water Supply Skid

Send your peak demand flow, required discharge pressure, and suction water conditions. YONGFAN application engineers will verify pump staging curves, select buffer tank volume, and provide complete submittal drawings.

Flow: 8–5,500 m³/h Head: 20–250 m Accuracy: ≤0.01 MPa Buffer Tank: Φ600–Φ800 mm Up to 8 Pumps Cascaded Modbus RTU / BACnet IP
YONGFAN application engineers reviewing booster skid drawings
Direct Application Engineering Support
Hydraulic pump staging, buffer tank sizing & certified GA drawings.