Originally Posted by steelpony5555
Hmmmm ...had an RV tech tell me that these furnaces need 4-5 open registers or it can cause problems with your furnace....
I guess it depends on the furnace. My 30,000 btu Suburban furnace has a sail switch which senses the air flow. If it does not sense enough air flow the switch will not close and it will not allow the igniter to fire so the burner will not light. They tell you in the manual not to restrict any of the registers for this reason.
I am fortunate that FR designed my 5er properly and the few times I have ran the furnace I haven't noticed any problems. If the bedroom /bathroom did get too hot I would close off half of that register and install a 2 inch duct into my uninsulated storage area. Most of my duct work runs thru the insulated and sealed underbelly.