Brian Kehlmeier
Member
This site has been incredible to me for years and here is my chance to contribute.
Here in Columbus, OH, positive pressure testing is not available for rough inspection and in my case, I did not want to perform a test with water as failure would result in water damage to the existing interior (my project was a new room addition). The city described the test requirements to me; however, did not provide guidance on how to perform the test. I was able to figure it out and wanted to post this in hopes that it may help future readers.
This thread got me started down the right road, but not quite to the finish line: https://terrylove.com/forums/index.php?threads/dwv-vacuum-test.101382/#post-755774
I needed plugs to seal up the roof vent and the toilet flange, a cleanout seal, a ball valve to cut the suction quickly, a plug with a blow-out stem, a FNPT coupling, and a vacuum gauge. The plugs and cleanout seal were easily obtained and installed. The tire pressure inflator I use for my vehicles made inflating the seal to the proper pressure a breeze. I found a PVC ball valve at the big box store and screwed it onto the trap adapter with Teflon tape. I found a negative pressure gauge on Amazon, but the pool plug with a blow out stem had a Schrader valve on it and had to be returned. This is where I was stumped for a bit. I called Grainger and the product specialist was able to get me a CHERNE Mechanical Expansion Plug: Inside Pipe, For 2 in Pipe, Male 3/8 in NPT Bypass that fit my needs, along with a coupling so that I could attach the gauge.
The test requires -2psi, which I could obtain with my shop-vac; however I found that my vacuum cleaner got me up to -3psi. To perform the test, I reset the pressure in the gauge by using the rubber stopper, used the vacuum cleaner to create the negative pressure, then closed the ball valve. Here are photos of my setup. It was actually quite easy once I had the right pieces and parts.
Here in Columbus, OH, positive pressure testing is not available for rough inspection and in my case, I did not want to perform a test with water as failure would result in water damage to the existing interior (my project was a new room addition). The city described the test requirements to me; however, did not provide guidance on how to perform the test. I was able to figure it out and wanted to post this in hopes that it may help future readers.
This thread got me started down the right road, but not quite to the finish line: https://terrylove.com/forums/index.php?threads/dwv-vacuum-test.101382/#post-755774
I needed plugs to seal up the roof vent and the toilet flange, a cleanout seal, a ball valve to cut the suction quickly, a plug with a blow-out stem, a FNPT coupling, and a vacuum gauge. The plugs and cleanout seal were easily obtained and installed. The tire pressure inflator I use for my vehicles made inflating the seal to the proper pressure a breeze. I found a PVC ball valve at the big box store and screwed it onto the trap adapter with Teflon tape. I found a negative pressure gauge on Amazon, but the pool plug with a blow out stem had a Schrader valve on it and had to be returned. This is where I was stumped for a bit. I called Grainger and the product specialist was able to get me a CHERNE Mechanical Expansion Plug: Inside Pipe, For 2 in Pipe, Male 3/8 in NPT Bypass that fit my needs, along with a coupling so that I could attach the gauge.
The test requires -2psi, which I could obtain with my shop-vac; however I found that my vacuum cleaner got me up to -3psi. To perform the test, I reset the pressure in the gauge by using the rubber stopper, used the vacuum cleaner to create the negative pressure, then closed the ball valve. Here are photos of my setup. It was actually quite easy once I had the right pieces and parts.
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