Author: Sam Myers, Retrotec

When pressurizing a building with a blower door, did you know that extra tubing must be added to the Channel B side of your gauge if you are not using a Retrotec DM32? If this tubing connection is neglected, you will have a reading that is approximately 20% high due to the open Channel B port that is referencing the indoor pressure of 50Pa instead of the outdoor pressure. Therefore, the extra tube is needed to connect that port on Channel B to the outside so that it is referencing the outside instead of the pressure induced by the blower door.

However, the Retrotec DM32 automatically

Leakage to Outdoors and Advanced DucTesting Methods

-When is it required?
-Setup options
-Complex setups
-Additional leakage to the outdoors tests