Residential Steam Boiler Maintenance

If you reside in the northeastern United States there is a possibility you grew up or lived in a home with steam heat. That heating system likely was a huge mystery to you and chances are it was not serviced properly. “Civilians” are not supposed to service the boiler, plumbers are. Unfortunately, many plumbers also have no idea what they are doing when it comes to steam heat. If you chose to follow any of the steps in this article, I strongly recommend calling in a local licensed plumber who understands steam boilers and systems to review monthly boiler maintenance with you.

Monthly Maintenance on Steam Boilers
Every month during the heating season you need to drain water from the system. How much? I like using a 5 gallon bucket. There are two primary reasons for doing this.

#1 – Testing the functionality of the low water cut-off
All steam boilers have this vital safety device. Some are the mechanical type like the McDonnell-Miller #67 that have a drain valve piped on to bottom of it. Others are newer models that are electronic type that have a couple lights on the control.

Testing a #67 Low Water Cut-Off
Long Island PlumberIf you have a #67 type low water cut-off, its easiest to raise the thermostat to startup the boiler so you can check to see if the boiler turns off when you drain the boiler – thus triggering the LWCO.

Take a 5 gallon bucket and place it under the drain pipe. Slowly open the valve and allow water to drain out. Immediately to the left or right of the #67, you will see a skinny glass tube with a valve on top and on bottom. Give both of those valves a nudge. Just to free up the valves. Start turning “clock-wise” an 1/8th of a turn, then go back. (Do not touch the valves if rust or corrosion is present – you will do more harm than good – call a local licensed plumber for help)

Testing Electronic Low Water Cut-Off
Newer steam boilers have an electronic low water cut-off. These models have a brass probe threaded into the side of the boiler that attaches to a “black box” with a couple lights. Typically, to test these models the boiler does not need to be running. You should see a green light on the control that is always on. Another light will usually be red or yellow and only turn on when a “low water condition” is present – like when draining the boiler!

As you drain water into the bucket, you should see the water level in the sight glass start to go down. The water level will eventually reach a certain level and trigger the LWCO to turn off the boiler. If this does not happen, if water does not drain out or you drain more than 5 or 10 gallons of water and the boiler still does not turn off, call our local licensed Long Island plumber for a service appointment at the earliest available time.

If you do not check the low water cut-off monthly you risk having that device failing. If the LWCO fails, the boiler will eventually run out of water and, not knowing there isn’t enough water present, will continue to operate as normal. When that happens, the boiler will literally cook to the point where the gaskets between the giant cast iron sections will melt away. Your entire home will smell like a burning tire factory and you will write a very big check to the plumber to replace your boiler. Worse case, it may also burn down your house. You’ve been warned.

#2 – Keeping the boiler clean
If you have a steam boiler, your house was build in the 1950’s or earlier, maybe much earlier. Therefore those black steel pipes in your home that has been carrying steam and water for 60-100+ years is slowly rusting away. Those fragments of deteriorating metal pipe are eventually making its was back to your boiler and you need to remove it.

Remember that sight glass I mentioned earlier? Ideally, you’d like to keep that water looking as clean as possible. Cleaner the water, more efficiently the system will run. More efficient the system runs, the cheaper fuel bills you will pay. Makes sense!

In closing, one final thought. Most systems have these automatic water feeder valves. You should hear them run 3 to 4 times a month. If you hear the valve add water more frequently you are losing water which is destroying your boiler. You will eventually “cut a hole” at the water line inside the boiler – resulting in a boiler replacement. If you do not have a automatic feeder, same applies for you too!

Do not add water more than 3 to 4 times a month during the heating season. Period.



More Info

Special Offers

More Info

Maintenance Plans

More Info

How can we help?

More Info

Follow Mikey Pipes

(Owner at Pipe Doctor)


Subscribers on YouTube!

Subscribe to Mikey Pipes Youtube channel for the latest how-tos and HVAC tips

Reviews & Testimonials

Customer satisfaction is our #1 priority

T. Van Buskrik

This is my second year using Pipe Doctor for my HVAC maintenance. Mike and his technicians are simply the best in the business. They arrive on time, are courteous, and most importantly they know their stuff. They do the job right.

M. De La Torre

Mike and his crew replaced my waste pipes. They took their time and did a great job making sure there were no leaks and cleaned up after they were done. Will continue to use them for other projects.

J. Pearl

Had the original boiler in our house finally go. Within 24 hours mike was here to put a brand new boiler in and we are warm again. Would definitely use pipe doctor again!

J. Miller

Mike and his crew are fantastic. Aside from exceptional work which is evident if you watch any of the YouTube clips, Mike’s knowledge is out of this world. Not only does he know his stuff, he also spent the time to make sure I had a solid background of the inner workings of the system. That’s very helpful to a homeowner!

R. Philip

Pipe Doctor is definitely an A++ local business that is amazingly professional, more than reasonable in pricing, and super super fast. They do not skimp in on using the best product and the services that they provide is second to none. They finished my water heater install same day in the snow within 2 hrs from call, negotiating, delivery and removal. Will use in the future without a doubt. Pipe Doctor second to none!

Parrish Family

While we live several states away, we watch the videos that Pipe Doctor releases on Youtube. Mikey is extremely responsive on their social media platforms, even to people that are not their direct customers. If Pipe Doctor ever branches out to my area, we will absolutely use them for all our HVAC and plumbing needs.

D. Summers

My water heater stop working and I needed a replacement. I Called pipe doctor and within 3 hrs Mike showed up, looked at it, and gave me a reasonable price. Mike was very professional and did a great job. Keep up the great work!!!

J. King

Daniel and Mike did a great job repairing my Navien. They were here right away and fixed the issue I was having. I would highly recommend Pipe Doctor!

H. Bains

I have been following Mikey Pipes/ Pipe Doctor on his YouTube channel and having watched all of his videos I must say that he is one of the most honest contractors I have ever seen and his professionalism is incredible. It is so impressive that he always gets to the root of the problem quickly and always comes up with the very best solution on the spot. Anyone that hires his services must consider themselves lucky!

Peggy M.

Been Relying on These Guys for Years.
Good work, fair price, quick response, and nice guys who are professional and know their stuff. They’ve never disappointed me.

S. Gordon

Pipe Doctor is such a pleasure to work with the customer service department is so efficient. The plumbers were on time and a pleasure to work with. Mike G is a real professional not only is he meticulous in his work, he cleans up and makes the place look cleaner than when he would started. Would highly recommend their service.

Skip to content