Our 24' C (Nexus), came with a 35,000 BTU, 4 vent furnace. It only needs to run for 5 or 10 minutes tops bfore driving the temp up to 70 something. We set the thermostat at 65 when we go to bed and even with outside temps down into the low 30's/40's it will only kick on once or twice during the running for about 5 minutes each time. The thermostat is on the wall above our bed so it is easy to kick it up to 70 in the morning without even getting out of bed.
The coach is heavily insulated and holds the heat in or out as needed. The 13,500 BTU ac consistently gives us 20+ degrees below the outside ambient temp. As noted earlier in this thread the Maxair Turbo with its fan and motor located up and out of the coach works very well quietly moving lots of air, rain or shine. A lot of RVs come with inadequate heating and cooling systems and that is a tough and expensive problem to cure.
We are 20 miles northwest of Lake Tahoe on the Truckee River at 6,500' and it dropped into the high 30's last night... not a problem.
