pianotuna wrote:
Otherwise known as a spit valve.
DrewE wrote:
There's usually also a little fill level vent valve thingy that is cracked open to determine when the propane is filled up to the maximum 80% level--one watches to see when liquid rather than gas spits out while filling the tank.
Ok I have all that with this tank, so I am gradually getting the picture of what I have here. I found an old hand-out tucked away, that is "Handy Tips" from Manchester, dated 1985 that explains all about the tank etc. I have the usual Marshall regulator stuff, so that is all good.
So really all we have to sort out now on the LP side is the furnace cycling issue. I believe it is the old, probably original thermostat at fault as has been suggested, so that can be solved. The furnace works through its starting and stopping sequences properly, so all good there now. (After getting the bugs out of it--actual bugs like dead and half dead wasps :) )
Thanks for all the help everyone!