# Any reason to close the vent cap? **URL:** \ **Category:** General Discussion\ **Created:** [August 5, 2020, 8:47pm UTC](https://forum.formlabs.com/t/any-reason-to-close-the-vent-cap/28445 "2020-08-05T20:47:33Z")\ **Posts on this page:** 1\ **Showing post:** 6
**Author:** ![rkagerer](https://avatars.discourse-cdn.com/v4/letter/r/439d5e/32.png) [@rkagerer](https://forum.formlabs.com/u/rkagerer)\ **Post date:** [October 5, 2020, 2:20pm UTC](https://forum.formlabs.com/t/any-reason-to-close-the-vent-cap/28445/6 "2020-10-05T14:20:25Z")
> [@Prime Remotely?](http://forum.formlabs.com/t/prime-remotely/28941/6): > > More to the point, you should close the breather valve on the resin cartridge when you’re not printing. That’s the only thing standing between a leaky bite valve and a machine flooded with resin. If they let you prime remotely, people wouldn’t close that valve. And then they’d have a potential warranty issue if a cartridge leaks. So if you follow the recommended procedure, there’s no way to remotely prime because you have to be in front of the printer to open the cap. My printer is in my baseme… That’s a good point I missed. Closing the cap when you’re not using the printer could help mitigate against a leaky bite valve. > if I understand correctly you say the vent cap needs to be closed because the cartridge empties itself otherwise due to the resins weight > Really never happened to me > Did it to anyone? The bite valves were slightly notorious for problems. I recall seeing some reports of leaks (e.g. [1](http://forum.formlabs.com/t/leaky-cartridge-is-this-common/13999), [2](http://forum.formlabs.com/t/brand-new-white-v4-cartridge-bite-valve-came-off-during-print/20750)). Lots more reports where the scoring was too shallow and customers were instructed to use a knife to finish the cut through the material. I’m guessing the manufacturer had trouble achieving the desired control over tolerance and Formlabs may have shifted the spec slightly to the conservative side for a while. It’s also been proposed the rubbery material is [sometimes self-healing](http://forum.formlabs.com/t/bite-valve-faulty/19868/3). I expect things have improved since then, as I haven’t seen chatter about this lately. --- _[View the full topic](https://forum.formlabs.com/t/any-reason-to-close-the-vent-cap/28445)._