3800 Series

1. Make sure the patient is safe — swap in a backup unit if you need to.
2. Reproduce the complaint yourself and write down exactly what you see (screen, alarm, code).
3. Check power, battery, cables, accessories, and settings before ordering parts.
4. Then open the service manual above and follow its troubleshooting section.

No suction at patient port source ↗

• Clean or replace clogged supply/patient fittings

Gauge doesn't respond / slow source ↗

• Check gauge diaphragm seating
• Clear hole at top of view tube with small probe

Gauge piston discolored source ↗

• Fluid got inside: disassemble and clean

Won't shut off / high spike source ↗

• Replace quad ring (cut by dried fluid), then test

High droop or gauge flutter source ↗

• Clear brass orifice in diaphragm housing

Fails to regulate / erratic gauge source ↗

• Disassemble and clean piston/stem
• Seat retaining ring; no end play in view tube

Intermittent timing wrong source ↗

• Timing screw: CCW faster, CW slower

No/poor regulation source ↗

• Most likely aspirated fluid/dirt: clean fittings, disassemble and clean, replace seals