Running the HVAC blower motor continuously can have an impact on the pressure differentials in the home, lowering the pressure on the lower levels. This can cause more soil gas to be sucked into the home. If there is radon in the soil, then it will be pulled into the home.
If you haven’t tested your home for radon gas yet, I would encourage you to do so. One out of fifteen homes in the US have a radon problem, and the only way to know is to test. If you have tested your home for radon gas, and running the blower motor continuously is something new for you, then you should test for radon again. Testing is very easy to do and doesn’t cost very much. For more information about radon, check our radon information here.