Common Windmill Q&A

Why does my windmill head rock back and forth?

Usually, this happens when you have low wind speeds or winds coming from multiple directions vs. a head on wind. The rocking back and forth is due to the backpressure on the system. If you have your diffuser at 12’, then it will take about 5 pounds of pressure to push air thru the airlines. To build up 5 lbs. of pressure it might take a 4, 5 or 6 mph wind to get the head to turn. This is a normal part of operation, especially at low wind speeds or if you have inconsistent winds.

At low wind speeds, I can only get air to come out of one diffuser, why?

At low wind speeds, the windmill might only be producing .5 to 1.0 CFM of air. This is sufficient for one diffuser, but probably isn’t enough air to operate two diffusers. As your wind speed picks up, the second and even third (if you have one) diffusers should kick in if your valves are adjusted appropriately.

Why do you need a 2-way or 3-way valve when you’re running multiple diffusers?

Air will always go to the point of least resistance. If one diffuser is a little shallower or has a shorter airline, it will want to take most of the air. You’ll have to restrict the airflow to this diffuser with a valve system so that air is forced out of your other air stones.

Is there any other way to adjust airflow other than using ball valves?

Common Windmill Q&A’s

Yes, you can use a hydraulic needle valve to adjust the airflow if you want. These can be purchased online at Northerntool.com or Grainger.com or in your local farm store. Most have a ¼”, 3/8” or ½” female NPT threads on both sides. You can purchase a brass fitting with male threads on one side and a hose barb on the other side and connect it in-line if you want a more precise adjustment.

Why do you put your air stones in a bucket?

We sell several different styles of diffusers. Some have their own bases and some do not. The air stone diffuser does not have a base so we put it inside of a bucket to keep it out of the mud and the muck on the bottom and to also weight it down into something so it sits on the bottom flatly and pushes air and water upwards. We recommend adding some rock, sand or concrete to the bottom of the bucket for weight and tying a marker onto the bucket so that you can raise and lower it or move it if needed.

How often do I need to clean out my air stone diffuser?

Your air stone diffuser will give you the best performance if you clean it every year or two. If you raise it up and it looks clean, then just lower it back down. If it has mud, algae or other things clogging the pours, then it should be cleaned. You can use a 10% solution of muriatic acid or give it a gentle cleaning with a steel brush. Putting it into a clean bucket of water and blowing air through it after cleaning is a good way to make sure the pores are open and that it’s operating correctly. If you have a rubber membrane diffuser, it may not need to be cleaned. You can check it by blowing air through it to check it’s performance.

What do I need to do for maintenance on my windmill?

Very little. We use high quality sealed bearings so there is nothing to grease inside of the compressor. You might have to change out the diaphragm and check valves every 4-7 years. Other than that, you should periodically check your air stone diffuser and clean it if necessary every year or two.

How long does it take to build and install a windmill aeration system?

This can vary greatly. If this is your first windmill, then figure on taking one day with two people to build the tower and head assembly and a second ½ day to physically set the windmill, anchor it and run your airlines and diffusers. Most people do this over a 2 day weekend or over several evenings. The key is to make sure you have plenty of time and don’t get in a big hurry.

Should I use a secondary anchor system?

We strongly recommend using a secondary anchor system. We supply 4’ ground stakes but encourage people to set these into concrete (either as a footing or as a pad). The second alternative is to use a screw in earth anchor and to set this in the middle of the windmill tower. You can then use plastic coated cable and tie into the three sides of the windmill to secure it.

How far can I set my windmill away from my pond?

You can set your windmill up to 1000’ feet away from the pond and still aerate it. We see minimal friction loss with air, especially with our larger ½” airline.

Do you sell parts for other windmill aeration systems on the market?

Yes, we do carry a full line of replacement parts for most aeration windmills. We manufacture these to our high quality performance specs and offer a guarantee that they’ll work or we’ll give you your money back. We have replacement blades, blade braces, hub assemblies, domes, tail arms, tail fins, tower pieces, stake clamps, diaphragms and check valves. All of our parts are offered at a lower price than the original equipment manufacturer.

What are your most popular accessories for the windmill aerators?

Tower hinges are our #1 accessory and make it much easier to install a windmill or to service it. Weighted airline is #2 in that it lets your airline sink to the bottom of the pond vs. having it floating on the surface. This keeps it from getting caught by boats, swimmers, fishing hooks, etc.. Either a freeze control system or pressure relief valve is also very popular in that both protect the compressor in climates where you have may freezing. Lastly, we sell a lot of air stone housing buckets and air stone markers.

I live in an area with a cold winter. Do I need a freeze control system?

In Northern climates, we recommend either a freeze control tank or a pressure relief valve in most situations. The freeze control tank insures your airlines stay open in that they release a small amount of isopropyl alcohol into the airline to unthaw it if it freezes due to condensation. The pressure relief valve is an alternative to the freeze control tank and releases back pressure at about 20 psi. This protects the compressor should your airlines ever freeze but doesn’t unthaw them. If you’re running multiple diffusers, you may not need a freeze control tank , especially if you split the airlines coming down the windmill tower as you have a lower probability of multiple airlines freezing at once. Please call and we’ll evaluate your situation.

Can you pump water with your windmills?

Yes, we can pump water. We have two water pumps (one vertical and one horizontal) that can pump water. They have a maximum of 40’ lift and will produce from 1 to 3 gallons per minute of water when the wind is blowing. We also have a 2” airlift pump that can fit in smaller casings and can go deeper in some applications. Most of our water pumps are used to pump water out of a shallow well, cistern, pond or creek to fill stock tanks, holding tanks or for water transfer where electricity is not available.