Fun found pipe in Dry system

[KGBeast42]

This really isn't a question but more a picture we took of a dry system we were inspecting. Believe it or not the owner really thought it would be just fine.

This is a short piece of 2 1/2" pipe taken out of the end of a dry pipe line. We tried to flush the lines but after attache about 40' of additional pipe to get it outside the debris restricted the flow to a point that we couldn't get a reading on the pedo.

I just thought it was interesting.

 

[ContractorDave]

Nice

Not so unusual in dry systems that have not seen regular inspections / maintenance. See my pic attached also.

So what did you do with the system? How did you go about cleaning it or did you replace some of it? In my experience, flushing a system with this degree of obstruction is next to useless.

Regards
Dave

 

[SprinklerDesigner2]

How long were the length in service for each of the systems in the photos?

Pretty nasty.

 

[PEDARRIN2]

Was the debris from corrosion products or was it MIC?

I have a garage project where an adjoining garage (same owner) has a dry pipe system and has a MIC problem - so much that the owner started having leaks within 6 months.

The owner has started to use nitrogen instead of compressed air to minimize the moisture introduced into the system.

My research indicates MIC can be a big problem in dry pipe systems.

 

[cdafd]

or is it that the dry pipe systems are not drained enough after being tripped??

 

[KGBeast42]

We just took over the inspections of this project and are currently researching our options to fix this. My Construction manager has found a company that has a product that will allegedly break done the material and allow the debris to be flushed out. It should also protect against future problems (so their web site says). I will get the URL when he gets back tomorrow.

At this point we are not sure how much of the system is affected. All of the points we have checked have been just like this.

Oh ya, I forgot to tell you my favorite part. The system is fed with a 6" ductile underground being reduced to a 4" OS&Y to the 4" dry valve. If you were paying attention there is no backflow device or even a single check valve installed.

Makes me glad I don't live there.