dometic fridge has sealed (if drain cap is in place, which it always
should be), externally vented combustion chamber.

in the unlikely event of TC failure, gas will make its way out of van.

domestic water heaters take combustion air from "inside the house",
TC failure could let propane leaking into living area.

this is why it is not an apt example.

alistair

On 5-Nov-10, at 8:24 AM, Dave Mcneely wrote:

---- Alistair Bell <albell@shaw.ca> wrote:
> different mechanism in the van. default is valve closed/gas off. TC
> keeps it open, barely
>
>
> home furnaces and water heaters are not an apt example in this case.

If the flame is burning, the thermocouple is hot, and keeps the valve
open.  if the flame goes out, thermocouple cools, valve closes.
Identical operation in hot water heater standing pilot, furnace
standing pilot, and Dometic refrigerator burner.

David McNeely