I have discovered the problem.
Radon fan in attic.
Thanks everyone on the feedback concerning humidity and attic insulation.
The purpose of a radon fan is to draw radon from out of the soil below the home and release it safety above the house.
Instead of having the fan and venting pipes on the outside of the home the only visible component on the outside is the vent stack that rises through the roof.
In cold environments this condensation can freeze and effect the life of the radon vent fan.
If the radon fan is located in the attic of the house or garage you can wrap the fan with fiberglass insulation.
When a radon system is installed in the attic space the fan and all electrical components are also located in the attic.
I noted the rh and temp in both the crawl and home with the radon fan running and i did it in the evening hours so the.
Benefits of a radon mitigation system installed in the attic the radon system is hidden.
The air flowing through the fan will maintain the fan temperature.
First and foremost rather than having the fan and venting pipes on the outside of the home an interior system means that the only visible component on the outside is the vent stack that rises through the roof.
Radon fans and electrical components are out.
Radon mitigation system information.
Radon systems create condensation within the suction and exhaust pipes.
Attic installed radon mitigation systems offer the benefit of hidden system components while protecting the radon fan from the elements.
Electrical components are out of reach.
A garage attic installation runs pvc piping from the sub slab radon collection point created in the slab through the garage where a radon mitigation fan has been installed.
After documenting the temp and rh in both the house and crawl space i have discovered the radon fan is somehow bringing humidity outdoor air into the building envelope.
Garage attic sub slab depressurization systems are installed in homes or businesses with slab flooring.
I have never found a radon fan more than a bit warm even if the motor has been stalled by some blockage so there appears to be no concern about causing a fire from the fan overheating.
Attic installed radon mitigation systems.
In retrofit situations the attic installed system is usually installed through a garage with the radon vent fan in the garage attic.
Radon fan i e an active system or an electrical receptacle installed in an accessible attic location near the radon vent pipe i e a passive system to facilitate future fan installation if needed.
Radon fans are better protected from the elements.
