Check particle monitor for leaks

Written By: Tanya Taylor (and 2 other contributors)

Difficulty

Moderate

Steps

Time Required

00:10:00 - 00:15:00

Introduction

A leak can be caused by loose connections, worn seals (o-rings) or split tubing.

If a leak occurs, this can affect the flow rate which will have a big impact on the accuracy of the measurement.

To understand how often you should perform this service activity, click here.

No tools specified.

Enter service mode so any fluctuations in the data caused from this activity can be excluded from air quality reports.

Adjust the sample flow by pulling the adjustment knob outwards, turning the knob to increase/decrease flow, and pushing the knob back in to lock when desired flow has been reached.
Fully open the sample flow adjustment valve, which is located on the face plate of the pump module.
On older monitors, the sample flow adjustment valve is positioned at the bottom of the enclosure under the PDI cover.
Block the purge flow by pinching the purge tube.
On older monitors, fully close the purge valve by pushing the valve handle towards the pump module.

Stop the the sample and purge pumps by pulling out the black and red power cables from the electronics module.
Count how long it takes for the pressure to change by 10 kPa.
If the pressure change (leak rate) is greater than 10 kPa in 10 seconds, you'll need to check for loose connections, worn seals (o-rings) or split tubing.
For example, if the needle moves from -70 kPa to -60 kPa in 20 seconds, this is OK, but if if moves from -70 kPa to -60 Kpa in 8 seconds, this indicates a leak.