SP Scientific VIRTIS 2K, Руководство оператора

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Appendix A: Troubleshooting VirTis BenchTop 2K, 4K and 6K
40 Rev 007, 10/11
© SP Scientific 2011
If none of these suggestions eliminates the vacuum problem:
1. Change and flush the oil in the vacuum pump.
2. Disassemble all vacuum tubing connections, clean with a mild alcohol (such
as methanol), apply a light coating of vacuum grease and reassemble.
3. Check all threaded and welded connections and seal with vacuum sealant.
If poor vacuum persists, or if testing vacuum with a calibrated gauge indicates a good
vacuum reading, the problem is likely related to the vacuum probe. Replace the
vacuum probe and retest.
Note: If this does not resolve your vacuum problem, contact SP Scientific for assistance.
Product Melting
The most common reason for product melting is poor vacuum. Adequate vacuum is
required to keep products in a frozen state. Check for a vacuum leak or possible
restrictions in the vacuum hose as described in the previous section.
If the unit is functioning properly but the product is still melting, the product’s freezing
point (eutectic temperature) may be too low to remain in a frozen state. Retest using a
water sample to determine if a mechanical or product-related problem exists.