The Steamboating Forum

What is considered the best water level to run an Ofeldt at? Top of the coils in steam space or water above the coils?

The drawings (SBA WTB2) show the top sight glass fitting about an inch over the top coil position suggesting that the water level should be a little below the top of the coils, but at some point in the past the sight glass has been re-located some 4 inches higher so that it straddles the top coil position. Bottom leg is off the water column, top leg is from the very top of the boiler. This has meant also meant a dog-leg in the bottom feed and naturally a higher water level.

Any thoughts? I'm re-casing the boiler at the moment; should I leave the glass high and run it with the top coil submerged or lower the glass and run with the top coil in steam space?

Cheers!

I built an Ofeldt boiler in 1996 with a steel drum and silver soldered copper coils. Originally, the bottom of the gauge glass was at the bottom of the top coil, but the silver soldered coils proved sensitive to low water levels and I lost a coil when the water level dropped a bit. I reworked the glass so that when water was visible in the glass, all tubes were flooded. This has worked well for 20+ years, and also appears to be best for steam production.

Note that these boilers produce steam rapidly, and the steam bubbles tend to affect the level of the glass significantly when drawing lots of steam. Whistles tend to cause the water level to lift, so flooding the engine is easy if one's whistle is large.

I'd run the water level as high as possible w/o flooding the engine when blowing the whistle.

- Bart

I'd run the water level as high as possible w/o flooding the engine when blowing the whistle.

I agree.

I believe that having the coils submerged especially when firing up is advantageous. With them submerged, circulation starts immediately once the fire is lit. With the water level below the outlet of the coils, the water in them would remain stagnant until steam started to form and pushed water out of their tops. In boilers, anything that promotes circulation is good.