Samsung Dryer Keeps blowing fuses

Model Number: DV328A
Brand: Samsung
Age: 6-10 years

I have a Samsung front load dryer that won't heat without blowing thermal fuses. Through a process of elimination I have replaced the heating element, the thermostat, the thermal fuse, the thermistor and the control board. The vent from the dryer to the outside is clear without any blockages. I checked it as well as a dryer vent cleaning company. The dryer will heat and dry just fine if it is allowed to run without be attached to the exterior vent, or when attached to an old pair of women's hose to catch the lint. However, as soon as it is hooked up to the exterior vent, it will run a partial load and then the thermal fuse blows and we are back to no heat again. While running without being attached to the vent, i have measured the heat levels and it cycles between 138 and 158 degrees, so I don't believe it is overheating. I have gone through 5 thermal fuses trouble shooting this. Anyone have a suggestions as to what else might be causing the fuses to blow?

I am assuming that this dryer has worked )OK at this location in the past.
Also that the vent cleaning company knew waht they were doing and also checked that the outside vent louver/s opened properly.

I would check the blower wheel.
It could be that it is stripped or loose on the motor.
Runs OK without the vent but the vent adds some back pressure to the system and then it slips reducing air flow, at least that is the theory.

I'll be interested in the outcome of this. I have a 3 year old LG dryer that is doing the exact same thing.