CAUTION

Excessive Gas Supply Pressure

An improper or excessive gas supply pressure can lead to an overpressure in the detector that can cause the safety valve in the detector to release gas. In extreme cases, the excessive pressure can cause the gas filters to rupture. This can pose a health and safety risk.

  • Observe the gas supply pressure range that is specified for the detector. Do not exceed the maximum gas supply pressure.
  • If you use high-pressure gas cylinders as gas supply, double-check the regulator outlet pressure to ensure that it is within the gas supply specifications of the detector. This is especially important when attaching the gas bottle for the first time and when changing gas bottles.
  • If the overpressure relief valve is releasing gas as a result of an overpressure in the detector during operation, turn off the detector immediately. Remedy the situation as described in Resolving Gas Supply Overpressure.

When

The gas supply pressure has exceeded 620 kPa (6.2 bar, 90 psi). The detector cannot pressurize properly.

The overpressure relief valve on the gas inlet inside the detector will open and release gas pressure to prevent damage to the detector. This creates a loud hissing sound.

Follow these steps

To remedy the situation, follow these steps:

  1. Turn off the pump flow and then the gas flow:

  1. Turn off the pump flow to the detector. Wait at least 5 minutes. During the waiting period, the detector drains any remaining mobile phase to waste.
  2. Turn off the gas flow on the detector.
  3. Wait until the system pressure is down to zero before you continue.
  4. Turn off the gas supply to the detector.
  1. Check that the gas supply pressure is within the allowed range. For the allowed range, see Performance Specifications.

  2. On the gas supply, turn on the gas flow to the detector. Follow the instructions depending on the situation:

Situation

Steps

The gas supply pressure has fallen within the allowed range. The overpressure relief valve will remain closed.

  1. Turn on the gas flow in the detector. See Turning On/Off the Detector Gas Flow.

  2. Check that the nebulizer gas pressure reading has returned to the allowed range: In Chromeleon, check the Gas Regulator Pressure parameter.

  3. If the problem persists, check if the gas pressure on the nebulizer certificate matches the nebulizer gas pressure set in the Gas Regulator Pressure Nominal parameter. If not, adapt it to the value given on the nebulizer certificate. Check whether the Gas Regulator Pressure parameter has returned to the allowed range.

  4. If the problem persists, contact Thermo Fisher Scientific Technical Support for assistance.

The overpressure relief valve is still open and releasing gas while the gas flow in the detector is turned off

If the problem persists, contact Thermo Fisher Scientific Technical Support for assistance.