Is it possible to “find” more leaks with a phx42 than any of the older FID analyzers (TVA1000B, TVA2020 or phx21)?
Yes, this may happen in some circumstances.
A primary technical improvement in the phx42 was to address and resolve one of the historical limitations of portable FIDs resulting from relying on the sample probe to provide the sample of the chemical being tested AND the oxygen for the hydrogen flame. This is in contrast to state-of-the-art rack mounted and other types of analyzers designed to collect, test, and produce results based on pure samples of the target chemical(s) while providing filtered, scrubbed oxygen from a secondary source.
The phx42 is designed to do just that. The sample probe provides just enough flow from the point of inspection, supplemented by a continuous flow through a scrubber mounted on the side of the analyzer. This enables the phx42 to run a sample flow rate lower than any other portable FID (reduced from 1 l/min to 300ml/min).
The results in several advantages:
- Less “bad stuff” comes from the sample site, potentially fouling the filter and other analyzer parts.
- 3-5 times longer filter life.
- Significantly extended pump life.
- Less maintenance and reduced operational cost.
- The lower flow rate reduces dilution at the probe tip, resulting in a more accurate analytical assessment of what is being sampled. (In a sense, when a phx42 finds a leak, it is designed to and capable of using the lower flow rate, “sipping” in more of the VOC and less of the adjacent ambient air. This gives a purer sample of the VOC since it is not diluted by the “extra” ambient air that was needed for the older FIDs.)