Milwaukee & Madison Area



North Eastern Wisconsin Area


[email protected]

Proper System Operation

The U-tube

Every week you should take a look at the U-tube on the Radon system vent pipe in the basement. This simple practice can tell you many things.

Check that the levels are uneven, that’s showing a vacuum draw. If both sides are at zero or level, there are a few things that could cause this:

  1. Make sure that the fan has not been turned off outside. An outside Radon system will have a white or gray box with a flip-up cover or a switch next to the fan. If you have a system routed to the garage make sure the plug did not somehow come unplugged.
  2. Check all the GFI outlets in your home & garage to make sure they did not trip off. A GFI outlet has two buttons on it. One says “test” the other says “reset”. A GFI cuts the circuit of electricity if something goes wrong, like if you drop a curling iron into the bathroom sink. If it has tripped off, reset it and check the U-tube. If it trips off again, replace your GFI. A GFI can become defective at any time.
  3. Check the top of the vent pipe for ice. If it becomes covered with ice, it will block the vent pipe. The fan may sound like it is running but air is not leaving the pipe showing a 0 – 0 on the U-tube. Shut the fan off, and then clear the ice out of the pipe. Once the ice is clear you can turn the fan back on. You do not want ice falling into an operating fan.

What if you hear ‘gurgling?’

The exact opposite situation from what I described above, can happen when something is blocking the bottom of the vent pipe in the basement. The U-tube may show a resistance a little above 2” or above 4,” depending on which fan was installed. This is almost always caused by water. This causes a gurgling sound towards the bottom. Go to the sump pit and service the sump pump. Either the pump is no longer working or the float is stuck, preventing it from turning on. Take the lid off the pit and replace the pump or float. Reseal the pit by cleaning off the old caulk and reseal using clear silicone caulk. The putty around the ejector pipe can be reused.

If you do not have a sump pit/pump, it may be still be caused by water but you have no way to pump it out. You may have to wait for the soil under the slab to dry out. A better fix is to add a suction point further down the foundation and connect it to the original suction point. There will be a fee for this but it will alleviate the problem.

Another thing to check is whether or not the system is drawing air from your home. You do not want this to happen because it will cause a loss in heating and cooling, costing you money. Sometimes there will be a structural shift by the foundation wall or slab. If a large gap forms where the wall and slab meet, or if a crack in the slab develops, it may need to be sealed. To check, light an incense stick and hold it near the gap or crack. If the smoke gets drawn down into the slab then it will need to be sealed. Use a polyurethane-based caulk, not silicone. Silicone will not adhere to concrete long term and can shrink/pull away, whereas polyurethane doesn’t shrink or pull away and lasts much longer.

Does the fan make loud noises?

Bugs in the fan.

  1. There could be bug/larvae build up on the bottom of the fan (see picture at left) causing a vibration because the bearing is being thrown off balance. Remove the fan and clean the fins on the bottom. If the bearing is not ruined it should be quiet again. If we do this there could be a charge.
  2. The bearing in the fan has failed. It might sound like a grinding noise with loud vibration. If it is still under warranty there is no cost for the fan, but there could be a trip fee to replace it.
  3. If the top of the vent pipe is covered with ice blocking air flow, the back pressure can create noise. Remove the ice as I described above.
  4. Most systems are very quiet, and most people do not notice any noise associated with it. On occasion, these systems can uncover structural problems that weren’t a problem until the system was installed. By this I mean there could be a loose stud in the wall or maybe a window was not installed properly during construction. Once a system is installed, it can cause these things to reverberate noise. Sometimes we can hear this right after the system is installed, sometimes it shows up later.

We have a few tricks to quiet a system, and do not charge for this, but sometimes one system will be louder than another. We will do all we can to quiet a system. Keep in mind that when you have something new, like a Radon system, you will be listening for it. It is a fan and it moves air. Normally you will not be able to hear it inside the home, but you might.

I have a large fan right above our den and can not hear it, but if I sat in that room listening for it, I bet I would. Consider your furnace operating or your air conditioner. They should be much louder then our system but after while you don’t notice them. I recommend you live your life day to day and try not to listen for the fan/system. Play the radio or TV, or even get into a book, and you will notice the noise less and less. It’s not that uncommon for a customer to ask us back to quiet a system, and once we arrive we have to stand still and listen for it. It may not be noticeable when we walk in. Some people have more sensitive hearing, and in that situation, there may not be much we can do.

As a last resort, a muffler can be installed on the system at a cost, but they do reduce air flow.

Keep in mind that you should do a Radon test at a minimum of every two years to ensure your Radon levels are staying low. You can purchase one from your local hardware/home improvement store, online, or buy one from us.

Please call us at 844-569-7236 or 866-569-7236 with any questions.