BY GEORGE LANTHIER
2. If the burner goes out at the“ minimum safe level” drain the cutoff by opening its drain valve. On probe types this step isn’ t required. 3. Shut off power to the unit. 4. Remove the float and switch and visually check the float and bellows. With probe types remove, clean and
28 NOVEMBER 2025 | FUEL OIL NEWS | www. fueloilnews. com
Figure 4-4
inspect the probe, Figure 4-4.
5. Replace the probe and / or the float assembly back into the boiler replacing any defective components and leave the feed valve closed.
6. Turn the power back on, the burner should not start.
7. Fill the boiler back up to its normal operating level. As the boiler reached its“ minimum safe level” the burner should have restarted proving the boiler was“ off on low water”.
By doing it this way you determine that it was working when you got there and was working when you were done. A great idea, since nothing beats fixing it! In addition, if it doesn’ t work“ as designed’ you can fix it. If we can get the customers to really flush the cutoffs weekly and we check and service the cutoffs properly yearly the boilers might just be around a while.
As long as were talking about water levels and such let me give you some more of my tricks-of-the-trade. But first, let’ s see check your knowledge of things you work with every day.
Starting off, do you know the flow rates for most pipe sizes that would be used on a fresh water( potable) feed to a residential steam boiler, specifically ½” and ¾” pipe and at a working pressure of 55-60 psi?
Second, do you know the average water content of a typical four section steam boiler for oil( about 135,000 Btus)? How about the same boiler for gas? Now come a couple of dilemmas, how do you fill that boiler slowly and how do you protect the boiler from overfilling both manually and automatically? We’ re going to take that up next time. See ya! l FON
George Lanthier is the owner of Firedragon Academy( www. FiredragonEnt. com), a 35-year-old Massachusetts Certified School teaching gas, oil and other heating subjects. The Academy has its training facility in Webster, Massachusetts. Lanthier is the author of more than 60 books and manuals on HVAC subjects, published by Firedragon. Lanthier is a CETP, ESCO, NATE, NORA, PMAA and PMEF Proctor and has been a Massachusetts Certified Instructor since 1975.