Steam Boiler Water Level Problem

daveycrockett

I just had a new Burnham Steam Boiler installed to replace an old American Standard. This is for an apartment building and most of the piping is one pipe with cast iron radiators. The system is pretty old. Some of the piping on the first floor is two pipe. The system originally was set up for gravity drain. Two days after the boiler got installed the water level started to act up. It bounces up and down really fast and then it will go down low enough to trip the manual reset LWCO. The near boiler piping is set up correctly for a gravity system but the a boiler feed was installed. If the water is changed out, the boiler water level will behave normally for about two days and then go crazy after that.  Maybe the boiler feed is too blame.

Big Ed_4

Skimming Oil

New install ? The oil floating on the top of the water line needs to be skimmed off

daveycrockett

Skimming Oil Reply

Yes, this is a new installation. It's been in operation for about a month. The contractor supposedly cleaned the sections to remove any of the oil on them. The water in the gauge glass does have some suds to it. How does the oil cause the water level to become erratic? Thanks

Hap_Hazzard

Oil on the water.

It increases surface tension and forms a barrier that makes it difficult for steam bubbles to escape until they expand and coalesce to become big enough to break out, and when they do it's a much more violent, energetic event that sprays massive amounts of water into the escaping steam exiting the boiler. All this water is going out into the system, pooling in pipes and radiators, then gradually returning after the boiler shuts down. The delay in condensate return is probably what's causing the low water condition.



Wet steam doesn't carry as much heat as dry steam, and it damages vents and shortens the life of the piping and radiators. Meanwhile, the fluctuating water level is shortening the life of the boiler, so you have a system that operates inefficiently, makes noise, wastes money, and wears out before its time.



Skimming is critical. There's no substitute for it. Draining the water removes some of the oil, but most of it lines the inside of the boiler as the water level goes down--remember, there's a lot of surface area in there! The temporary improvement lasts about as long as it takes that oil film to boil off the walls of the sections and float back to the top. To get rid of it, you have to skim. As for cleaning the boiler sections prior to assembly, that's a nice theory, but, well, you don't need us to tell you it didn't work.



One thing that can help to make the skimming process faster and easier is the addition of some washing soda (not baking soda!) to the water. Use about 2 oz. per 100 ft² EDR or whatever your IOM recommends. Washing soda makes the water more polar which repels suspended oil droplets and prevents them from dispersing. You should drain the boiler completely when you're done.