Warm CCD shouldn't be a problem if you are imaging planets but for longer exposures it may add some additional noise. DMK21 at 11,5 sec needs a good dark (and I was imaging 81P comet at 11,5 sec exposures). For long exposures (planetary nebula, comet hunting?) sticking a peltier unit on the housing shouldn't be a problem (peltier, radiator, fan and more cabels
) For shorter nice cooper radiator and some silicon termoconducting glue should help if needed