ventless gas fireplace - figuring size needed

have a converted garage attatched to house so it is now a family room, purchased a ventless propane fireplace to use as a supplement heat source on cold winter days or for ambience when in room, room currently is heated by hydronic baseboard 2 walls, room dimensions are 20x12 with vaulted cieling of 15', no door on room open to entrance area and leads into kitchen and living room and dining room , no doors open layout . figuring approx 2880 cf of space in family room, approx 7880 cf total with combined rooms ( small cape w/ bedroom upstairs approx 1700 sf living space), heat home with pellet stove located in living room. is the size of the vented gas fireplace of 26,000 btu sufficient or overkill ?

26,000 btu is more than plenty to supplement your existing heat source for a room that size. Make sure you have a CO monitor in that room if you're using ventless gas...

LP too! Can you un purchase the vent free unit and buy a inexpensive vented one? if its a garage, no reasob you cant just pop a hole in the side of the building? Vent free LP is not going to smell like a dozen roses...

12,000-26,000 is the range i would be looking at. You can turn some down 30% and some down 50%. Most vented fireplaces can run on a thermostat, vent free ones cant.

You're probably going to want a ceiling fan in that vaulted ceiling to push the warm air to where you are. You'd be amazed at how much a ceiling fan on low can do.

Have to say vent free does put out more heat but not my first choice. Direct Vents in my opinion always the best for heat with still being able to vent.

thanks for answers on fireplace, we had purchased the ventless fireplace on sale last year and redid the room into a gameroom, probably won't use fireplace that often, only for ambience on occasion while in room,looking for an external regulator for the propane tank, requires a regulator to reduce incoming gas pressure to between 11 -14" wc, also the insert requires an 3/8" inlet connection to pressure regulator, is this a similar regulator like on a gras grill, fireplace is only 26,000 btu's.have been looking on internet for regulators, little confused as to what size to purchase. any help on this would be greatly appreciated. thanks - ken

what manufacturer and model fireplace you have?

not sure of mfg, believe it to be procom, bought at lowes, unit is 26,000 btu item # 030334 vent-free gas fireplace insert, model # ssfbd28t

what if you have a vent free but crack the damper say an inch or two?
does that cut down on humidity

yup