Since it was the temperature that caused the tomatoes to fail, it is the temperature that you have to address. The lid not opening at the most inopportune time is secondary as failures of mechanical devices are inevitable. First a similar system. You may be familiar with how an automobile water cooling system works. Now change the system to air and substitute the automobile with the cold frame. You now have an emergency air cooling system(fan) controlled by a thermostat (electronic switch). The thermostat is selected for the desired emergency exhaust temperature, when that temperature is reached the exhaust fan removes the heated air. Easy to build and test. Thoughts? Jerry
@ waretrop: tx @ KK Ng: out of the 50 seedlings only 5 recovered, so all the others are new seedlings. And no, there are no peppers, only tomatoes.
Bummer. Sad for you, too. I feel so wasteful when I make a mistake and my plants die. I almost killed a hightunnel full of cabbage and broccoli this spring. I went away for the day and it got sunny heating up the house to close to 100 or more...ooops! good thing my husband came home and opened it.
