Dave has given you some good pointers here and I think that the cool outside temperature was probably the cause of the high levels of condensate, however it would be useful to have some more information.
What were you smoking and how long were you smoking it for? You mentioned that the CC maintained 250-275 F for
most of the cook - did it fall significantly below this at any point or at the end before you took the meat out? Where were you measuring the temperature? With such a tall CC it is possible that you are getting quite a temperature gradient as you get higher up. Next time you may want to also take the temperature of the gasses in the flue to see what the temperature is at the top of the smoker. If they are significantly lower then the CC will be acting like a big reflux condenser.
I would not use a water pan in this setup. The water is really acting as a heat buffer to smooth out temperature spikes in the fire box from reaching the CC. Use the pan but fill it with sand instead of water and it will do a better job and will not cause any additional humidity. Were you using it during this smoke?
Dave may be right about the position of the flue but as your smoker is really the same concept as the
WSM I am not so sure. This has the exhaust vents at the top and does not even have a flue. In an offset smoker the flue is required to draw the hot gasses sideways through a horizontal cooking chamber whereas in your smoker the heat is doing what it does naturally - it is rising. Before you make any structural changes I would try other, less invasive, things first.
As Dave also mentioned, in the cooler outside temperatures some insulation could help to reduce the heat loss through the CC walls that is contributing to a temperature gradient towards the top.
A few suggestions to try:
- Make sure you cook the meat on the racks at the top of the CC and ensure that the desired temperature is maintained there. That way you will know that you don't have the top of the CC cooler than the cooking area, allowing condensation to form.
- Measure the temperature of the gasses as they come out of the flue. This will also help you to check the temperature gradient.
- Use sand in your water tray in place of the water.
- If the meat is not cooking on the top rack then place a ring of foil or a foil tray on the rack directly above to prevent any condensate that may form at the top of the chamber from dripping on to the meat.
- In cold weather place a welding blanket over the CC to help insulate it and help prevent the chamber walls from cooling too quickly
It takes time to get to know any new smoker and I am sure that you will soon master this one