Is my furnace working correctly?

hohenwald48 wrote:

DutchmenSport wrote:
Unlike a house where you can adjust the vents in each room with a forced air furnace system, a camper does not put dampers on the vents or in the heat ducts. They are all wide open. Air movement is going to take the path of least resistance, and the first hole air can come out of it the one that gets the heat.

Put a pillow over the vent closest to furnace, and I bet you'll feel the air and the heat every where else. You'll need to figure out a way to regulate each hole in the floor to adjust an even flow.

Some say you should never cover a vent. Hogwash! The air out-put size (square inches), only needs to be the same same size as the air in-put on the furnace. In a house, the intake is usually fairly large, 20x30 inches or even more. The vents in each room are, maybe 6x8 inches, maybe 8x10. 3 - 8x10 square inch vents would add to 24x30 inches, that's almost equal to the air intake size. So, as long as you kept 3 vents open, you furnace would always have 100% air flow. Open any more air vents in your house and the flow begins to divide up, becoming less and less forceful.

Same is true in your camper.

OK, forget my ramblings, even I'm getting a headache! Just put the pillow over the vent closes to the furnace and see if you get air in the other vents.


EDIT:

And remember, if your camper has the "Arctic Package" some of the heat is going under your camper. (I'm not saying the Arctic Package works... I'm just saying some of the heat is going under the floor).

It's not "hogwash".

Actually, the output requirements are based on the BTU output of the furnace and the flow rate of the fan incorporated in the furnace. The size of the output requirements is based on a complicated set of calculations done by the furnace manufacturer and usually specified in the installation manual.

Additionally, the square inch requirements are based on the size of the duct or on the size of the vent, whichever is smaller. If an 8x10 vent is supplied by a 4" duct it still only provides about 12 square inches of output size. It has been my observation that TT manufacturers install only the minimum required ducting and any blocking of ducts can often result in furnace overheating due to restricted airflow. But it's your rig, do what you want.

One more thing, you might want to check your math. 24x30 is 720 square inches and 3 8x10's only equal 240 square inches. You need about 9 8x10's to equal a 24x30. If those 8x10's are fed by a 4" round duct it would require about 60 outlets to equal the 24x30.