Having used a single Southern Burner to heat an 8x12 greenhouse for
many years, we find it can't quite keep up with the heating demand in
our new 12x16 greenhouse. We'd like to add another heater that does
not require a chimney pipe. Rinnai makes a couple of direct vented
models that are probably more efficient than a Southern Burner, but
with the added complexity of fans and considerable electronics. We
wonder if the humid atmosphere would damage such a sophisticated
heater. Please share your experience using a Rinnai or similar direct
vented heater in a greenhouse. Fred in Lakewood, Colorado