I have a MT Vernon AE free standing it is installed corner out 4" vent with O.A.K I have a 45 degree and total of about 3 ft of venting with end screen. It is an 09 model and has all the updates. I do know alot about these units but have one problem no one can answer. I clean my stove weekly and clean and leaf blow the venting monthly. The problem is after start up the stove howls until it warms up. I've taken the O.A.K off no change. I tried taking end screen off no change. I tried different settings on the control board auto, manual 1 2 3 4 5, softwood, hardwood, utility. I took out the intake baffle no change. I thought of back pressure and expansion of air through the stove. I do know inserts do howl when warming up due to the vent length but should not apply here. I switched to corn and was worse. I checked the ash pan gasket it seals all the way around but the noise does get louder if I remove the ash pan. I wonder if the tach in the combustion blower is off and over reving or if any one else here has heard or seen this problem and I'm missing an easy fix.
Thanks in advance.
Thanks in advance.
