This topic came up because I was testing out the new MR45 digital recovery machine. That machine goes off by itself when it hits a 20″ Hg vacuum. It's a cool feature, but it is good to know when that level of vacuum is overkill and when it's not enough according to EPA requirements. You […]

Friction rate is a value located on a ductulator. We use it during the design phase of a duct system to predict the operating static pressure of a duct system. The challenge with friction rate is that it is often misapplied by folks using a rule of thumb (ROT). In order to apply friction rate properly, […]

When I started in the trade in 1999, there were still many oilable blower motors in service. As part of the maintenance, we would remove the housing and oil the motor. We would also vacuum the motor and wipe it down. As oilable motors have become extinct, I see fewer and fewer techs pulling the […]