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My boiler is over filling

shycam Member, Email Confirmation Posts: 1
edited May 5 in THE MAIN WALL
Hi everyone, 

My tenant’s boiler keeps overfilling every time it is low of water. It fills all the way to the top and the only way that it doesn’t make that banging pipe noise is if I either manually feed the water myself or when it does overfill, I turn off the emergency switch so I can dump some water out. At one point, it would overfill so much that water would shoot out of my tenants radiators and would shoot out from the returning water pipe. The sounds are unbearable.. I live in New Jersey and The bedroom is in the basement. As you can imagine all the pipes run over there so I hear everything. When the water is at the right level, the boiler makes a really loud swooshing sound which I believe is the water being boiled. That sound is tolerable but the banging sound is so loud and I can’t sleep nor can my tenants. I have had many plumbers come to my house. They all give me different reasons. One said oh there’s a lot of mud in the pipes.. so they charged me $ to drain the boiler to clean the pipes with this solution. I don’t think it did much as the tube is still dirty and lots of dirty comes out whenever I drain. One other guy told me that the boiler is too big for that apartment.  And that I would need to purchase a smaller boiler or completely install a new water heat system. He told me it can cost about $... and honestly, I can’t afford it.  I need guidance and help.


  • Jamie Hall
    Jamie Hall Member Posts: 15,858
    The boiler gets low on water and all by itself overfeeds and floods? Is that correct?

    OK. Somewhere on the water supply piping going to the boiler is an automatic water feeder, and it is controlled by a switch on the boiler which senses the low water. Either the feeder isn't working properly, which is quite possible, or the switch on the boiler isn't -- which, if the boiler has been neglected and the switch is the float type is quite likely. The float gets stuck down if the mechanism isn't blown down regularly.

    Can you post a picture of the boiler, showing all of the controls? And find the automatic feeder on the water supply piping to the boiler and take a picture of that? Then we can probably suggest what needs to be done. Even if you have to hire someone ;to fix the problem, it's an easy and cheap fix.

    So far the plumbers you have had in obviously haven't a clue. They may be good plumbers, but... either they are incompetent or they are taking advantage of you to line their pockets.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • aperson
    aperson Member Posts: 66
    Try to at most pay half and then tell them you'll wait for the invoice. If they don't fix it don't pay.
    EBEBRATT-Ed Member Posts: 9,014

    Check "find a contractor on this site"

    There are several good ones in NJ. @EzzyT & @clammy
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,477
    Can you check the operation of the low water cut off, (stopping the burner when the level gets low), and valve off the water to the auto-feed, and watch the boiler waterline for a couple of cycles? This should temporarily stop the overfilling.
    It is possible that the cleaning solution put in by the plumber is responsible for some of your troubles with this. Draining out all the water, and refilling would remove the chemicals. They can sometimes cause such a violent boiling as to throw water up into the pipes, instead of just steam.
    We await any pictures you may send us to give further advice.—NBC
  • Lance
    Lance Member Posts: 149
    I am sorry you are in this mess. My advice is strictly optional. We plan to fail when we fail to plan. Step 1. Search and find one honest, trustworthy and competent contractor. You will have to set standards that many of us will easily agree to. Insured, licensed, referenced. You may have to go through hundreds of companies. Start with those listed with authorities, recommended by manufactures, or other reputable sources. Perhaps anyone who had a great experience. or step 2) Go to school for this trade, apprentice for 6 years, and learn to do it yourself. Just expect to pay far more for this education than what a great contractor will charge you. Absolutely do not pay for anything that will not work, no matter how expensive or cheap it is. or Step 3, which is where your are now, seeking advice, finding out how to do it. Just be aware there are many causes and many reasons, singular or combined that cause your systems problems.
    Start with learning the minimum requirements to see if your system meets those requirements. You may even need a consultant to review it first. A good plumber may not be an engineer, or a heat expert, or control expert, or even a steam expert. You do not need a plumber, you need a steam heat pro. Remember with many hands come many mistakes. If you are paying, we need to show our competency. If we cannot not, we should not be hired. I have a list of things that number over 50 that can go wrong in this stuff. So far, all my customers that listened to me have been very satisfied with the results even if they had to be told twice. It is hard to judge one good answer from 10 wrong answers when you judge by the majority and not the facts. There are thousands of false answers, but only one right answer. Most of my customers' systems like this have at least 3 problems. 1) what is broke, what is wrong or caused it, what is maintenance. And sometimes we have to remove the previous mistakes by others. PS. Residential steam is a controlled system and deserves a slow rate of makeup water. Lower the water feed pressure to no more than 10 PSI. on a 1/2" pipe. A new boiler is never the solution, if the problems are elsewhere.
  • MikeL_2
    MikeL_2 Member Posts: 290
    edited May 10
                   Does this boiler have a tankless coil for domestic hot water? Tankless coils can develop a leak & overfill the boiler. 
                    Is there a manual bypass &  valve piped around the auto feed valve? Manual valves can fail & allow a tiny, continuous trickle that will over feed your boiler.
                  Sludge or mud can also accumulate in the return piping & slow the flow back into the boiler - this can also contribute to overfilling.
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