Propane burner check valve.

[Out of Character - 0]

I was cleaning yesterday and used the hot water tap on the front of the machine. After a few seconds it started puking steam. That means that the pressure from the hot water in the boiler reverse flowed back to the machine. The machine was on and pump was running. This means that when we shut down it back flows all the time until it cools.

Are you guys running high temps using a check valve to prevent this.

We set our burner temp at about 275. Some people have said you can't go that hot and still have any flushing. With short 50 ft hose runs or before I turned the burner down to that temp I have seen those temps at the wand and with our set up it flushes well.

Here is what I don't understand. For some reason it was puking steam and interrupting the cooler (180) flow from the machine. If I didn't know better I would agree you can't clean with that. But with the burner at the same temp I can hook the wand up directly to the burner and see good even flow. My only guess is that pushing the water through the jets makes a even flow, using a open hose it was sporadic and uneven.

I used to use a heat gun to check temps but these tests were done with a new digital lie detector.

 

[Greenie]

As part of shut down, I always idled the machine, and bled off the steam vapor, once it was a solid stream of water I would shut it off.

But I seldom went over 250º

 

[Duane Oxley]

That's not the only reason it could be releasing steam...

If you run out of water and air gets in the system, internal pressure drops and steam occurs...

By opening the hot water outlet on the front of your system, you also decrease the pressure, and steam can result.

Under pressure, the boiling point of water raises. It's well over 350 degrees, at about 10 PSI...

What kind of system / heater, etc., is it...?

 

[Out of Character - 0]

It's a w/m p1200 pto, one of the few with dual coolant exchangers. I have a little giant 3ht at the back door.