No-Dig Underground Sprinkler Repair – All It Takes Is A Heat Gun!

I developed this irrigation repair technique out of desperation. A sprinkler head had launched from the ground right next to me one day and landed in a flower pot. The resulting geyser was spectacular, but the location was horrible!

The area around this particular sprinkler was surrounded by cobblestones and bricks, and worse, right up against a fence. To make matters more difficult, he had installed a French drain just a foot away! The elevator nipple was missing. Sure enough, a replacement standpipe wouldn’t even begin to thread! Obviously the broken part of the nipple was stuck in the T-connector, way underground! Before developing this technique, I would have had to dig lateral trenches about 2 feet long on each side of the connector, cut the supply lines from each end of the connector, add a sleeve and spacer, and then glue a replacement tee. . . Not this time! There was just too much involved in digging this connector out of the ground!

I have a special tool that I bought at The Home Depot just for this problem. It is the PVC variant of an “easy out”. Unfortunately, it wouldn’t work! I couldn’t get enough pressure (the connector was buried almost the entire length of the extractor) and kept scraping my knuckles against a fence post. The standpipe was not PVC, it was vinyl. It was so slippery that the extractor’s knife edges didn’t bite into the inside edge.

But vinyl melts! I have a 1200 watt heat gun I had bought it to remove paint. The extractor tip is metal and using this heat gun, I heated up the extractor tip. very hot hot! By pushing the extractor straight down the hole, it gently melted into the broken nipple, deep underground! I let it sit and cool for a few minutes before giving it a whirl. Two seconds later, the broken The nipple was removed!

After bolting on a replacement riser, I cycled the sprinkler pump to that area to rinse out all the dirt that had gotten into the connector. I put a new sprinkler on the replacement riser and guess what? That irrigation repair was done. Not just done, I didn’t have to dig a shovel of dirt!

The trick was to heat the extractor tip hot enough to melt it into the broken vinyl mouthpiece to grip.

A few weeks later, I had a different problem. I had installed new planters along the side wall of my house and wanted to use my underground irrigation system to water the new flowers. I had a plugged riser right where I need to put a 4′ riser. Unfortunately, this was an old steel standpipe that I had run into several times on the mower, and when I removed the tube, it left the threads on the tee stripped and clogged with rust flakes! Unlike most of my irrigation repair projects, this line is very shallow. Shallow enough to scratch the top to really see the damage.

There was nothing he could do to screw the new riser into place, he was going to have to replace the T-connector, or maybe not. I have a fairly complete shop and have metal working tools to make holes for screw threads or cut external threads for bolts. Since I had to go to The Home Depot or Lowe’s anyway for a replacement tee, why not see if they had a pipe threading tool?

The Lowe’s staff laughed when I asked for a tool to cut the 1/2″ internal pipe thread for an underground PVC tee. Their only advice was to dig it up and replace it. No way! The Home staff Depot didn’t laugh out loud, but also suggested replacement accessories.

I bought the accessories, but I also found the perfect tool: an 18″ long 1/2″ steel pipe! Once again, the 1200-watt heat gun came to the rescue. By heating the end of the tube, the thread section, I was able to submerge it into the buried tee. It sizzled as it sank in and I quickly worked it in deeper as I screwed it into place. Without letting it sit, I unscrewed the steel tube to prevent it from being welded in place. I repeated this several times until the entire threaded section of the pipe was inside the tee nipple.

Guess what? The new 4′ replacement PVC riser screwed itself in! Through the use of steel wires, pressure, and heat, I was able to partially melt the underground tee and cut new wires. Not a shovel full of soil was dug up for this irrigation repair!

Since then, I have helped neighbors with their irrigation repair projects that have left them in awe: “you can cut new threads underground without having to dig.” Wow, thanks Bill, thank you very much!

Not all irrigation repairs can use this technique. Let’s face it, if your tee nipple or connecting pipes crack or break, you’re going to have to dig. But try this tip first and see if it works. You’ll know in minutes if there’s a more serious problem. You’ll get wet standing there, but you’ll quickly see a bump around the head of the running sprinkler if there’s a broken pipe or cracked nipple. Oh well, at least you gave it a chance!

i had this cheap $20 heat gun for more than twenty years. Not only does it do a great job lifting paint, I’ve used it for electrical boat repairs (heat shrink tubing), removing self-adhesive vinyl tile, contact paper, and sanding discs, and even starting fires in my coal pit. This is NOT a hair dryer – keep it safe, keep it away from you at all times.

In conclusion, I was able to use my cheap heat gun and cheaper steel pipe to apply enough heat and pressure to re-mold the stripped internal threads, and enough raw heat to allow the edges of another tool to cut through material that, without that tool, would have required much earth digging for these simple irrigation repair projects.