Q: I have several humidors and in need of large quantities of PG solution. I also use a few electronic humidifiers. The manufacturer recommends distilled water with no mention of PG. Have there been tests done to determine if PG will work more efficiently in an electronic humidifier such as the Cigar Oasis brand, and if so, does XIKAR sell gallon size bottles of PG Solution?
– Brian Singer in Illinois
A: For this answer, I went to the experts…
Great question. Let me give a little background on PG and then answer your question. Please take no offense if this is old news to you.
The primary reason for PG being used in the regulation of humidity is it’s hygroscopic nature. PG absorbs or adsorbs water vapor in order to maintain a water density equilibrium between itself and the surrounding environment. PG evaporates at a negligible rate (it’s boiling point is 240 F) and is a viscous, sticky liquid. This is the reason we inform consumers that a 50/50 PG solution will eventually clog up a foam or crystal humidifier – the 50% PG stays behind much longer than the 50% water. The PG ratio in your humidifier slowly goes from 50/50 to 75/25 to 100% PG. It’s full of PG that is pulling all of the humidity out of the air! (100% PG will dehumidify to nearly 0% RH).
PG gives XIKAR humidifiers their two-way nature – the PG will adsorb water vapor to raise relative humidity (RH) or absorb water vapor to lower RH. Without PG, a humidifier filled with water only will humidify until the RH reached 100%. The PG is necessary to keep the RH at 70%.
When it comes to active systems like a Cigar Oasis, the humidifier adds water vapor to the environment as necessary but prevents unwanted evaporation. The water reservoir is enclosed in such a way that the water is not exposed to the air or allowed to evaporate freely. Active humidifiers are designed to be one-way – they add humidity when necessary but they cannot reduce the humidity.
So, to answer your question – since PG added to an active system will be unable to help regulate the humidity downward due to the enclosed reservoir, it offers no benefits while you would be taking the risk of clogging up your Cigar Oasis or causing damage to the fan. While PG vapors won’t be flowing through the fan in high concentrations, the presence of liquid PG near the system is risky.
– Rob Lembke
VP, Engineering & Process Excellence