Make sure to calibrate the new one when you get it. I bought one similar to yours with the probe and it was 7% off. I now only use my faithful cigar humidor hygrometer and it works perfectly.When I went to bump up the RH for lockdown I candled and they had very large air spaces but I could see movement in a couple. At this point I discovered that my RH gauge which had been faithfully reading 45% was not working and the wells were dry... At this point I though well what can you do just keep going and correct the problem, so I did the lockdown and put a napkin over the wells in the incubator and soaked everything. Before long the moisture on the windows started to show up so i Knew the RH was coming up, but my gauge was faithfully showing 45% still. I have only one gauge so I just had to wing it and I went to bed. I didn't sleep and at 2:00am I got up and looked in the incubator... yes still 45% Grrr....now I know i wasn't supposed to open the incubator but I did it real quick and whipped the gauge out and whacked it and put it back in.... it started to read 75% and has appeared to work throughout the rest of the hatch. Yesterday I ordered a fancy new one with temp and RH in a remote probe..
so long story short I figured running as high as 75% might just give the chickies enough moisture to compensate a little for their earlier losses. Currently I am running a 33.3% hatch rate with shipped eggs if 2 more hatch it will be a more normal 50%. SO don't give up it seems that they can still hatch even with such large air cells!!!!there are still three in there but it's day 22 today (or 21 depending on where you started counting) so I am giving them a little more time but I think I am done. all 4 of the babies are doing well so far.
