Baking Components @ <5% RH Is this Really Needed?

Also Humidity Chambers can go below 20% RH Only.

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Look into dewpoint calculations. Then find the dewpoint for the ambient air where the oven is. Then calculate the RH of the oven at full temperature at that dewpoint and temperature.

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Hi Armando- You don't need a "Humidity-controlled oven" to achieve <5%RH in your baking process. I have (3) Grieve 333 ovens that are used for various bakeout/drying processes. All get their make-up air out of the room they sit in. I can go as low as ~65C and still be below 5%RH. I'm looking at a plot of one of them right now, below, that was running 115C overnight and the RH% ranged from 0.12 to 0.19%. This is measured by a Vaisala HMT333 I installed for monitoring purposes.

They don't have RH control; that's just the level they achieve. If you're wondering, the RH of the room where this one is located was 45% during this same period. While that theoretically has an impact, it's a minor one, with the chamber temperature being the dominant factor.

So you don't need to be elaborate. I can only speak to the Grieves we use but you'll likely get similar results with other manufacturers. All that said, if you want to CONTROL the humidity, they aren't the right tool but for MSDs, drier is better.

I have no connection to Grieve other than having purchased about (10) of their ovens for various curing and drying processes.

Good luck.

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