Difficulty maintaining temp on long cook

I’m doing my first cook today longer than just a few hours. We’re cooking a beef roast for 24 hours at 135 degrees. At 12 hours the temp was stable. However at the 13-14 hour point I noticed the temp starting to drop (down to 127.5 and falling as I type). I checked to ensure the bag wasn’t touching the Anova (it wasn’t) & also to ensure the water level was between the min & max levels (it was) and the temp continues to drop. I even adjusted the desired temp up to 140 to see if that would help & the water temp continues to fall (down to 126.6 now). Any advice that anyone can offer?

What is your cooking vessel? But I’d suggest you may need to contact support. I’ve never had any issues holding temperature.

+1 for wanting to know the vessel / cooking environment. The electronics in the head of the unit are prone to overheating if the APC isn’t in a well ventilated area (never run it in a cupboard or put it in the corner of your countertop, underneath overhead cabinets, where the hot water vapour can accumulate).

If that isn’t the scenario, then, yes, you need to contact Anova Support.