Can damage be done to these incubators by high temps?

[Rodney Williamson]

I have asked the Nor-Lake if their walk in Models NA50RL-1 and NA50RS-1 can be 
raised to the 60 to70 degree range for a day or two by means of an electric 
heater.  They said "Don't go above 55."  Feeling that this may be an 
appropriately conservative response for a manufacturer, I wonder if someone 
has already raised these incubators to higher temperatures to get rid of 
mites, and could tell me if any damage was done.  These "Evironmental Rooms" 
are joined by a connecting door and are controlled for humidity, light and 
temperature. They are normally run at 17 and 25 degrees. 

The incubators are obviously expensive and not my own,  but I am hoping to 
provide the owner with information that will help decide a plan of action.

Rodney Williamson