OPERATING INSTRUCTIONS
1. Close system OSY valve “A”
2. Open by-pass valve and “B” butterfly throttle valve
3. Purge meter, located on venturi, as follows:
a) Open station shut-off valves on venturi & vent valves
attached to meter. When a steady stream of water
passes through hose, meter is purged of air.
b) Close the vent valves after purging.
4. Start the fire pump, and read meter in GPM.
5. Refer to pump GPM requirement and
adjust throttle valve to meet the requirement.
6. After the test, open valve “A” and
close the by-pass and “B” valves.
| Pump GPM | Pipe Size | Venturi Style | Meter Range (GPM) | Venturi Length (Buttweld or Grooved) | Venturi Length (150# Flanged) | Venturi Length (300# Flanged) |
|---|---|---|---|---|---|---|
| 50 | 2″ | 685 | 25–100 | 3″ Buttweld / 4″ Grooved | 9″ | 10″ |
| 100 | 2 1/2″ | 746 | 50–200 | 3″ Buttweld / 4″ Grooved | 9″ | 10″ |
| 250 | 4″ | 744 | 125–500 | 3½” Buttweld / 4″ Grooved | 9½” | — |
| 300 | 4″ | 744 | 150–600 | 3½” Buttweld / 4″ Grooved | 9½” | 10½” |
| 450 | 4″ | 744 | 225–900 | — | — | — |
| 500 | 5″ | 715 | 250–1000 | 5″ | 12″ | 13½” |
| 750 | 6″ | 743 | 375–1500 | 6″ | 13″ | 14½” |
| 1000 | 6″ | 743 | 500–2000 | 6″ | 13″ | 14½” |
| 1250 | 6″ | 743 | 625–2500 | — | — | — |
| 1500 | 8″ | 750 | 750–3000 | 7″ | 15″ | 16½” |
| 2000 | 8″ | 750 | 1000–4000 | 7″ | 15″ | 16½” |
| 2500 | 8″ | 750 | 1250–5000 | — | — | — |
