Running a Derr boiler
Posted by: Kelly
Date: May 01, 2015 12:27PM
I've been asked to help recommission a car with a Derr boiler & burner. What are some of the differences in managing this system compared to Stanley?
Since it's still a water level boiler, I assume that water management is basically the same - operate the bypasses to keep the level where you want in the indicator, whether a sight glass or kidney gauge. But since there is less total water stored in the boiler, I imagine that the level will fluctuate more quickly. Maybe a good-working automatic bypass is a must for a boiler like this.
I don't suppose you can modulate the amount of fire - the gun burner is either running full-blast or it's not at all. I imagine there is a pressure switch to actuate it. Would it typically have its own fuel pump, so the Stanley pump & pressure tanks would be out of the picture?
Obviously the pilot system would no longer be used.
I guess blowing down would be the same - once at the end of the run, but I suppose it would be over pretty quickly.
How about firing up - get the right water level in the boiler, open the drip for superheater protection, and just start the burner and let it rip?
An old letter from the original purchaser of the Derr system says that he was unsatisfied, and that he thought Derr could have done a few easy things that would have made it a lot better. He didn't say what they were. It will be fun to see how well the existing system works.