The case of the damaged drain pipe, this Friday's case

RayWohlfarth

In this case, I was called to look at a replacement boiler for a brewery. The existing steam boiler was only five years old and already leaking. When I arrived at the building, I noticed a 3 foot wide trench in the parking lot that went from the building to the middle of the street. The boiler was set for close to 15 psi. The pvc drain pipe failed. The failure was due to the way the owner operated the steam boiler. Any thoughts? I think this one will stump you. I will post the video and the answer Friday morning.

EdTheHeaterMan

I hope he was not flushing the beer down the drain. That would be a mortal sin in Ireland!

Larry Weingarten

Hi, I imagine there is something about very hot water/steam, and PVC not getting along too well... 😏

Yours, Larry

GGross

this answer seems too simple considering you said this will stump us, but maybe the boiler being set to 15 PSI it would blow the relief valve , the relief tied to the PVC cause the PVC to fail, the trench resulted from all that relief fluid running out toward the street for 5 years, boiler took on constant makeup water due to relief blowing which helped bring about its early demise. I'm not really a steam guy I'm almost strictly hot water so I'm sure I am missing something here.

retiredguy

For me, the giveaway is the 15PSI pressure setting for the boiler's operating pressure. I think that the condensate entering the condensate tank was too hot for the pump to handle so the operator used fresh water to cool the condensate. This created an excess of water that had to be dumped somewhere so instead of routing it to a drain, which is illegal, he dumped it into this trench in the parking lot. The PVC could handle this still hot condensate and ruined it. There are condensate pumps that can handle condensate that is near the boiling point of water but they are expensive to purchase and install and these people were looking for the cheapest pumps available.

RayWohlfarth

Ok so in this case, the brewmaster / owner would drain the boiler after each brewing session. The hot water inside the boiler would go zooming into the PVC drain and turned it into cooked spaghetti. All because he didnt want to spend the money for water treatment. Crazy times. Here is the link. https://youtube.com/watch?v=dF2fx3URG_w

retiredguy

If this genius had a lot of money and actually wanted the boilers to last you could have sold him a deaerator, new boiler, water treatment and a service contract. If all he wanted was a new boiler I would do as you did and drive away as fast as I could.

CLamb

Nice video. Did you make the graphic yourself?

RayWohlfarth

@CLamb I use EDraw for my graphics

SlamDunk

A blowdown separator would have saved the drain pipe.

RayWohlfarth

@SlamDunk Yes sir but the owner saved money