MY BP and its hides

MY bp is about 1 yr old .I got him from a friend who was out of town alot and couldnt give him proper care.My set up is a 20 long glass w/ a screen top 2/3s covered to keep in humidity , 1 heat lamp that i switch every 12 hrs between night and day bulbs , 1 UTH on the lamp side and under a hide , on the cold side there is another hide . a large waterbowl in the middle and various fake plants. My tank temps during the day are 90' basking and 80 cold side, night time 85 basking and 75 cold side , hu.midity is between 50-60% .My BP eats every 10 days ( 3 mice ) and last ate yesturday, my question is why does he stay on the cold side 99% of the time , he came out last night for about 15min basked on the warm side the when right back to his hide on the cold. I have digital therms and hygroms so i know that my temps are good.

My snakes prefer the cold side most of the time also. As long as your temps are stable and the snake is eating, I do not see a problem here.

Hello,and :welcome: to BP.net.
Are you using a thermometer with a probe or a temp gun to measure the temps on top of the glass above the UTH? You didn't specify if you were using a thermostat to control it or not. If the UTH is too hot, snakes may not use that side, and if they do, there is a good chance they can get burned. But, if the UTH temps are good, and your BP eats consistently, and doesn't have any regurgitations, then you're ok!!!!