PSI & Tempurature

I read somewhere that the high pressure gauge on the regulator will read at a lower PSI at cooler tempuratures. Does this work the same for the regulators going to the kegs? I'm asking because I'm force carbing my first batch and the pressure on my regulator keeps dropping a point or two over every 8 hours or so. I've been cranking it back up to adjust for the loss in pressure. Should I be doing that, or should I leave it alone. I'm carbing at 45 degrees and 13 PSI.

Your cylinder of CO2 will read a lower PSI when chilled (Boyle's Law of saturated, pressure, temperture, contained).

The change with your regulator getting chilled maybe the result of materials used in the regulator, rubber in the diaphram, type of spring, etc...

So, I shouldn't adjust the psi when it fluctuates?

The low pressure guage should be correct. If it drops on you, then bump it up a little. Usually I have the opposite problem. It creeps up and I have to dial it back.

Maybe this would be helpful to someone...
I just measured high pressure gauge drop at lower temperature.
At 66F it shows 800 PSI and when cooled to 37F pressure is 510 PSI.

It matches up with C02 Liquid/Gas Chart:

BBL_Brewer said:

Usually I have the opposite problem. It creeps up and I have to dial it back.

Click to expand...

When I got home it was high and I had to bring it down.

Thanks for the responses.

Someone else just posted with the same issue. Yes, I think it's normal, when the diaphragm in the regulator is cold it can take a day or two to stabilize. Adjust as needed, and I bet you'll find that it's fine after a couple days.