http://confocal-microscopy-list.275.s1.nabble.com/Incubator-box-heating-mystery-tp6627357p6630505.html
Your problem might be the changing position of the termometer of the system, one interesting trial will be putting the overheating system in the non overheating system, to see if is that part fails or remain working as the trial you make the way around.
If your system is failing you should consider one incubator as the one we have, this is not the huge box making the microscope unreachable, it is the size of the insert in the stage and it has 4 points heating your sample, the cover, the objective used, and the water heater, we have never had a temperature overshoot as the mentioned by Michael, even if we open doors, or change room temperature ( recorded from 18 to 27°C) the shift in temperature observed trough time in the incubator is about 0.5°C over a 25h period. In such long experiments we have people reviewing samples as you dont want to let the confocal working if the sample has suffered unwanted changes, by the way the brand of the one we have is a INU - Tokai hit incubator.
> Date: Wed, 27 Jul 2011 12:01:32 -0700
> From:
[hidden email]
> Subject: Incubator box heating mystery
> To:
[hidden email]
>
> *****
> To join, leave or search the confocal microscopy listserv, go to:
>
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy> *****
>
> Hello everyone,
>
> I have a very strage problem with an incubator box heating up. I have two
> live cell imaging microscopes enclosed in PeCon incubator boxes (I think
> they are Incubator XL). The microscopes are in two separate buildings. One
> microscope heats up significantly past the set temp. (above 41 degrees, set
> to 37 degrees) even though the temp. is being measured and reported
> correctly to the electronics (confirmed by a glass thermometer). The other
> microscope works perfectly and holds at 37 degrees for days. The strange
> thing is that when I put the temp. control components that work well
> (heater, control electronics, temp. sensor, and all cables) onto the
> microscope that heats up, it still heats up, even though the components work
> perfectly on the other microscope! Any ideas why this might be happening,
> why the temp. control equipment works on one microscope but not on the
> other?
>
> The temp. equipment is stand-alone, not connected to a computer or to the
> microscope in any way. One microscope is a Zeiss Axiovert 200M (the one
> that works) and the other is a Leica DM IRE2 (heats up) in separate
> buildings; the incubator boxes surrounding them are very similar. Any ideas
> on this mystery are welcome.
>
> Thanks,
> Esteban