{"id":51592,"date":"2018-03-29T14:30:00","date_gmt":"2018-03-29T14:30:00","guid":{"rendered":"https:\/\/discover.restek.com\/uncategorized\/a-better-way-to-configure-your-ez-no-vent-gc-ms-connector\/"},"modified":"2025-11-25T21:43:53","modified_gmt":"2025-11-25T21:43:53","slug":"a-better-way-to-configure-your-ez-no-vent-gc-ms-connector","status":"publish","type":"post","link":"https:\/\/discover.restek.com\/de\/blog-it\/gnbl4563\/a-better-way-to-configure-your-ez-no-vent-gc-ms-connector","title":{"rendered":"A better way to configure your EZ No-Vent GC-MS Connector"},"content":{"rendered":"\n
\"decorative\"<\/figure>\n\n\n\n

If you are using the EZ No-Vent for Agilent mass spectrometers (cat.# 21323), you are probably tricking your instrument into working properly by inflating the length of your column in your acquisition software. If you have MassHunter, or a recent version of MSD ChemStation  (G1701EA), you don’t have to do this. Instead of configuring your 30 m x 0.25 mm ID column as a 112 m column, you should configure a composite column (see Figure 1). Even if you aren’t using the EZ No-Vent with your mass spectrometer, you should be configuring your column as a composite column because the 17 cm transfer line is heated by the transfer line heater, not the oven.<\/p>\n\n\n\n


\"decorative\"
Figure 1 – 30 m column configured as a composite column in MassHunter (without the EZ No-Vent)<\/p>\n\n\n\n

Figure 2 shows a composite column configured with the 17 cm x 0.10 mm ID vacuum restrictor, which is the part of the EZ No-Vent that allows you to disconnect your analytical column without turning off your MSD. You’ll notice the average linear velocity is significantly reduced when the EZ No-Vent is used (39 cm\/sec drops to 26.8 cm\/sec) even though the volumetric flow stays the same. This has some negative chromatographic effects.<\/p>\n\n\n\n


\"decorative\"
Figure 2 – 30 m column configured as a composite column in MassHunter (with the EZ No-Vent)<\/p>\n\n\n\n

Figure 3 is an example chromatogram collected on a 30 m x 0.25 mm x 0.25 \u00b5m column without using the EZ No-Vent. Figure 4 shows the chromatographic effect of installing the EZ No-Vent while keeping all acquisition parameters the same (aside from configuring the restrictor in the composite column).<\/p>\n\n\n\n


\"decorative\"
Figure 3 – Example Chromatogram collected without the EZ No-Vent<\/p>\n\n\n\n


\"decorative\"
Figure 4 – Same acquisition parameters as Figure 3, but collected with the EZ No-Vent installed<\/p>\n\n\n\n

The good resolution of the first eluting compound (1,4-Dioxane) and the dichloromethane solvent peak has collapsed, in Figure 4, and Aniline and bis(2-Chloroethyl)ether are now coeluting. The resolution for the two PAH pairs has also degraded. Lowering starting oven temperature 20\u00b0C improves the separation of 1,4-dioxane and solvent peak, though 1,4-dioxane is still on the solvent peak’s tail (see Figure 5). The PAH resolutions have also improved, almost to the level of performance when the EZ No-Vent isn’t installed.<\/p>\n\n\n\n


\"decorative\"
Figure 5 – Chromatography is improved by reducing the starting oven temperature.<\/p>\n\n\n\n

<\/div>\n\n\n
\n

Products Mentioned<\/h3>\n
\n
\n
\n
\n Catalog No. 21323 <\/a> <\/div>\n
\n
EZ No-Vent GC S\u00e4ulen-Massenspektrometer-Verbinder, f\u00fcr Agilent GCs mit 5971\/5972, 5973, 5975 oder 5977 GC-MS<\/div>\n <\/div>\n
\n Produkt anzeigen<\/a>\n <\/div>\n <\/div>\n <\/div>\n <\/div>\n \n\n\n
<\/div>\n","protected":false},"excerpt":{"rendered":"

If you are using the EZ No-Vent for Agilent mass spectrometers (cat.# 21323), you are probably tricking your instrument into working properly by inflating the length of your column in your acquisition software. If you have MassHunter, or a recent…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kadence_starter_templates_imported_post":false,"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"footnotes":""},"categories":[793],"tags":[],"industries-application":[],"post-badge":[],"resource-type":[],"product-library":[2529,2516],"resource-technique":[2332,2336],"hf_cat_post":[623],"ppma_author":[584],"class_list":["post-51592","post","type-post","status-publish","format-standard","hentry","category-blog-it","product-library-ferrule-raccordi-connettori-gc","product-library-prodotti-per-gascromatografia","resource-technique-gascromatografia-gc","resource-technique-spettometria-di-massa-ms"],"acf":[],"taxonomy_info":{"category":[{"value":793,"label":"Blog"}],"product-library":[{"value":2529,"label":"Ferrule, Raccordi e Connettori GC"},{"value":2516,"label":"Prodotti per Gascromatografia"}],"resource-technique":[{"value":2332,"label":"Gascromatografia (GC)"},{"value":2336,"label":"Spettometria di Massa (MS)"}]},"featured_image_src_large":false,"author_info":{"display_name":"DRCadmin","author_link":"https:\/\/discover.restek.com\/de\/author\/drcadmin\/"},"comment_info":0,"category_info":[{"term_id":793,"name":"Blog","slug":"blog-it","term_group":0,"term_taxonomy_id":793,"taxonomy":"category","description":"","parent":0,"count":442,"filter":"raw","cat_ID":793,"category_count":442,"category_description":"","cat_name":"Blog","category_nicename":"blog-it","category_parent":0}],"tag_info":false,"authors":[{"term_id":584,"user_id":0,"is_guest":1,"slug":"chris-rattray","display_name":"Chris Rattray","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""}],"_links":{"self":[{"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/posts\/51592","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/comments?post=51592"}],"version-history":[{"count":4,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/posts\/51592\/revisions"}],"predecessor-version":[{"id":56569,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/posts\/51592\/revisions\/56569"}],"wp:attachment":[{"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/media?parent=51592"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/categories?post=51592"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/tags?post=51592"},{"taxonomy":"industries-application","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/industries-application?post=51592"},{"taxonomy":"post-badge","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/post-badge?post=51592"},{"taxonomy":"resource-type","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/resource-type?post=51592"},{"taxonomy":"product-library","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/product-library?post=51592"},{"taxonomy":"resource-technique","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/resource-technique?post=51592"},{"taxonomy":"hf_cat_post","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/hf_cat_post?post=51592"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/discover.restek.com\/de\/wp-json\/wp\/v2\/ppma_author?post=51592"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}