Problems with 3/16 tubing clogging

[Gary R]

I was an early adopter to this tubing. Sap per tap has been great. However last year one of my three lines quit running and this year all three quit towards the end of the season. The problem is bacteria clogging at the tees. I have been cleaning the lines by sucking a bleach solution followed by clean water. After three years the lines look pretty good. You can tell when the lines are clogged by no sap moving and the drops are full of sap. I have had to cut tees out and clean them to get things running. This is a major pain to keep running. I did use the tees from Mcmaster Carr. I know there are tees out from CDL. Does anyone know if the ID is greater? A solution will need to be found or this system will have problems. Thanks!

[VTmaplehobby]

We were hoping to adapt a pressure washer at the end of the season to clean lines with a bleach or peroxide solution. Do you think this would help in a similar situation to yours or would you not find it worth the time with your experience with this tubing? This is only our first year with 3/16.

[DrTimPerkins]

...last year one of my three lines quit running and this year all three quit towards the end of the season. The problem is bacteria clogging at the tees.

THE FOLLOWING RESPONSE IS FROM TIM WILMOT, UVM MAPLE EXTENSION SPECIALIST AT UVM PMRC

Thanks for the information. I'll be looking out for this problem as the season progresses. In 5 years of testing 3/16 lines using hundreds of taps and fittings, almost all from McMaster Carr , I don't think I have ever seen a T clog toward the end of the season. A true test of whether this is happening would be if the lateral line is filled with sap behind the T. This year I have found a 3 such clogs early in the season, in lines that were used last year and not cleaned, or even drained properly. The problem was obvious because the whole line filled up behind the obstruction, which I believe was scum that had formed from last year's old sap. In all 3 cases it was confined to one T, which I replaced and this caused the sap to resume flowing. Moral of the story--I should have drained the lines better at the end of the season.
I'm not sure why T's would be clogging at the end of the season in the vertical leg (I assume that this is what is meant by this posting). I have collected sap until the very end of the season every year and never seen that. Tim Wilmot

[Gary R]

Hello Dr. Perkins,

The tees are clogging on the uphill side of the tee on the lateral and on the drop side. The laterals and drops are backed up full of sap. No movement of any air bubbles. As soon as I clean the tee the sap that is down stream flows down fast. The material can be white to black in color. There is very little visible bacteria in my laterals.

Say hello to Tim Wilmont for me. We met at the first LEME. Thanks

[Maple Hill]

Could it be a piece of wood chip from when you drilled the hole?

[steve J]

This is my second year with 3/16 I have yet to have this problem but will watch for it as season winds down.

[WESTVIRGINIAMAPLER]

I did have a couple minor problems with it this season. Made 80%+ of crop in March which was exceptionally warm and the 3/16 would sometimes run for a week or more after a freeze, so I am sure this contributed to it. All 3/16 was new tubing this year and all CDL fittings are exceptional quality and ease of use.

[Paul VT]

Yesterday I had one run with 15 taps that had just about stopped running. Found at the last drop before the tank that wood had plugged the tee. It had been dropping in vacuum level for a week. Wished I had looked harder sooner.
11611

[Gary R]

Last year when I had the problem I thought it was a piece of wood. I was very careful on drilling this year. I'm certain it is bacteria. If I knew the CDL was bigger I would just buy them and cut them in for next season.

Anyone who has followed my posts on 3/16 in the past knows I've had excellent flow, until now. Thanks for the ideas. Hopefully we'll work this out and I'm the only one with issues.

[DrTimPerkins]

If I knew the CDL was bigger I would just buy them and cut them in for next season.

Both the CDL and D&G fittings have somewhat larger internal diameters than the McMaster-Carr fittings.

[rchase]

I had three tees clog with wood chips from the tap hole. Sap was backed up and no vacuum on the gauge. Cleaned the wood out and back working now.

[ttowle3]

I had six long runs of 3/16" tubing of about 600 ft and great production in them all until near end of the season. I used D&G taps/Ts. I had 18-30 taps per line and the longest line of 800 ft with 30 taps was the best but stopped running suddenly a week ago. After checking and rechecking I noticed there were 3 red maples on the line and they had budded out. So I took the taps out of those trees and later that day the line was running fine again.

I stopped collecting sap 2 days later as it was getting too warm. For what its worth!
Soo... no more red maples on my high natural vacuum lines eh.


I had three tees clog with wood chips from the tap hole. Sap was backed up and no vacuum on the gauge. Cleaned the wood out and back working now.