A few days ago I noticed a fairly large piece of ice forming on the exterior of the fresh air intake duct in our furnace room. I used a blow dryer to melt the exterior ice build up, however, I can still feel a fairly large piece of ice and a bit of water on the inside of the duct.
I typically run my furnace fan 24/7, but set it to auto for now in case its making things worse by continuing to bring in cold air.
Are there any typical causes for this? ie. hole/tear in the insulated duct that's allowing the cool air to meet the warmer air inside my home and then condensate/freeze? Could my duct work be fine and its just the nature of these cold snaps?
As it gets a bit warmer I'm sure ill be left with a bunch of water inside the duct, is poking a hole to drain it manually a good idea? Or run the fan and try and evaporate it?
House was built just over 3 years ago. Going to contact my builder and see what they say, but was hoping to get some more input as well as I have little to no experience in the HVAC area...
Thanks
Few pics:
https://i.imgur.com/IqrRpwZ.jpg
https://i.imgur.com/w4FfIji.jpg