I'm posting this on the Basements forum because I think that's where a lot of the "radon pump" action occurs.... but here's the situation:

Our pump is in the attic. Our house is only about 4.5 years old, and our builder has a method of putting the pipe through the foundation in the basement, into the substrate, then up through the house, through the attic - venting out the roof. The radon barometer (the thing with the red liquid) is in the basement on the pipe....

Everything was fine for a few years. Then we started having a lot of noise/vibration that we could hear in our master bathroom (directly below the radon pump in the attic). My husband went up there at one point and smacked the pump casing... he could hear something rattle and fall down the pipe. We surmised that all the maple tree seeds from surrounding trees had fallen/blown into the pipe and were causing a problem. After that day when he 'smacked' it, the noise dissipated. But not long afterwards it started again. Funny thing is, sometimes it spontaneously stopped, and then started again... off/on/off/on/mostly on - and very noisy.

So, DH did some reading online about this particular fan, and others had complained. So he ordered a new fan and this morning he went up in the attic to replace it....

The plot thickens (literally)....

He put the new one in and brought the old one down and took it apart. Full of dead worms, "dirt", etc.... what a mess!!!!! So our new theory is: birds have been sitting on top of the pipe where is extends up out of the roof and (birds being birds) poop into the pipe. Birds carry all kinds of stuff (worms, bugs, germs, diseases, etc.) right? So is this a correct assumption by other's experience and common sense? And it certainly looked like bird poop mixed in with a lot of dead worm bodies.

My primary question, and I'll wrap this up:

Can we have someone install an elbow on the pipe up there? Will that impede the radon pump action or cause any other problem? Has anyone else experienced this and how did you solve it? Will a bend in the pipe prevent "stuff" from causing this problem again?

Thanks!!!