I have a 500 gal propane tank onsite, with a propane water heater, and baseboard boiler.  There used to be a propane fireplace, but it was removed long before we moved in. They left the propane line in place, but just turned off the valve.

Is hooking a big buddy as simple as connecting the line physically with needed adapters, or will I need some sort of regulator? I do have the "filter" for using 20 lb tanks. I have no clue what the pressure is of the line coming in the house, and I don't know what the standard pressure is for boilers and water heaters.

Interesting question. I have the Heater Buddy adapter and filter that I hook up with but I only hook up to 5 gal tanks with that. I have wondered the same thing. Tag for more interest.

Standard boiler and water heater pressures for LP are around 11"w.c. (read inches of water column)

FYI 1psi=28"w.c.

I tihnk that answers the question!

From the manual:

"NOTE: THIS HEATER MAY BE OPERATED WITH (1) OR (2) DISPOSABLE 1 LB. PROPANE CYLINDERS OR WITH A REMOTE REFILLABLE CYLINDER(S) MAX. 20 LBS USING (1) OR (2) F273701, F273702 OR F272702 HOSE ASSEMBLIES WITH FUEL FILTERS (F273699) ON EACH HOSE ASSEMBLY. IT MAY ALSO BE OPERATED WITH (1) F271802 HOSE ASSEMBLY CONNECTED TO A REGULATED (11” W.C.) PROPANE SOURCE OR (1) F271803 HOSE ASSEMBLY WITH 11” REGULATOR WITH ACME NUT."

Yup, unless there was something really odd about the old fireplace you're good to go. Just be 100% sure about your connections and regardless of the manual and built in sensors I suggest at least SOME venting, even if it's just a cracked window in an adjacent room with the doors open between them.

The heater already has a pressure regulator installed inside it. In order to use the heater on low-pressure propane, you would need to bypass it.

I've seen posts from RV'ers who have done it, connecting the heater to their RV's low-pressure propane supply.

There is also at least one wall-mounted "Buddy" heater that is factory-configured for connection to low-pressure propane - and dozens of wall-mount models from other manufacturers that will also operate on it.

The big buddy has a low pressure inlet also



 

That would be the QD side, no?