saladdin
Feeling the Heat
BBB is 99% worthless. I'd be surprised if you hear a peep.
Mine is a June 2011 model but I'm not having any issues. Thanks for the fix manual, will file it for future use.
Forgive me for dropping in here late and I started to read through the post but it was a little painful
Heatilator released a vacuum isolator box to remedy a problem that was known that was causing the pressure switch to lose vacuum when the distribution blower would come on under certain venting configurations, namely short runs like it sounds like you have. Part # SRV7074-183 . It is basically a metal box that mounts around the vacuum switch.
More recently they released a design change for Cab50's that were manufactured after 5/20/13 that changed the unit around a little bit to eliminate the low vacuum people have been having. Basically sealed up problem air leak areas and redesigned the back panel where the unit is sucking in air. See the attached pdf that breaks down the field fix for existing units. One tube of RTV will go a long way towards fixing any vacuum issues people are having.
Mine is a June 2011 model but I'm not having any issues. Thanks for the fix manual, will file it for future use.