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Season Startup for Large Hot Water Boiler

Tony_D Member Posts: 17
Our 28 unit apartment cooperative uses a one-million BTU boiler to supply hot water to baseboard radiators throughout. We have a plumbing company do the 'startup' each fall, consisting of a simple check of the mechanicals, pilots, burners, etc. and adding a cleaner/preservative chemical to the water. I'm not sure much more is done.

Every year, some of our members complain of loud clicking and, sometimes, banging for the first couple months of the heating season. By the end of the year, the noises are mostly gone. One year, we skipped the startup and, surprise, very little noise.

My question is, what should be done in a 'proper' startup for this type of system? We are in Michigan and the boiler was installed in 1967. It has two pumps; one services all units to the right, the other to the left. Also, there are two temperature setting units under the boiler's side cover. They are both set slightly differently, but set at around 190 degrees each. Can you tell me if these are upper limit, lower limit settings or just one for each zone?

Thanks for any insight!


  • Gilmorrie
    Gilmorrie Member Posts: 185
    The chemicals being added may cause the initial noise each year? If your system has effective air removal devices, you might be able to skip the chemicals. Photos and the type of materials used in the boiler and and piping might help decide.
    EBEBRATT-Ed Member Posts: 15,327
    The two controls are likely an operating control that turns the boiler on and off and an additional high limit control which is a safety back up control set at a slightly higher temperature, 190 is the correct setting I would set the operator ther and the high limit at 200. It's not that critical

    Don't know about the clicking.

    The boiler fire side should be checked for soot as well as the smoke pipe. If the combustion is good, these probably don't need cleaning every year you can probably go 2-3 years depends if it is gas or oil fired.

    They should do a combustion test every year, and check the operation of all safety and operating controls every year. The burners should be checked and cleaned as necessary......don't know what you have.

    The pumps again don't know what you have but couplings should be checked if they have couplings some motors and bearing assemblies need grease, some need oil, some are sealed bearings
  • Tony_D
    Tony_D Member Posts: 17
    Thanks for the great input. I personally oil the motors and the impeller assemblies every two months during the season. I don't recall anyone checking the smoke pipe. Don't believe we've ever had a combustion test. Had the burners checked and cleaned only a couple times in the last 15 years, so perhaps all that is overdue.
  • Tony_D
    Tony_D Member Posts: 17
    Thanks, Gilmorrie. Maybe we will skip the chemicals this year and see what happens. I'll try to get some pics in the next few days.
    JUGHNE Member Posts: 11,021
    edited October 2020
    If these pumps are the typical 3 piece such as B&G 100 series (which are pretty small) it is easy to over oil the motor.
    Too much oil will leak out and soften the motor rubber mounts causing them to sag. Then the coupler has to flex more and that leads to wear. You can see the motor mounts get egg shaped, they should be perfectly round on the inner ring.
    I oil them once a season.

    Include the pumps in your pictures please....plus an end shot of the motor mount.
  • Tony_D
    Tony_D Member Posts: 17
    Thanks, Jughne. Good advice. I believe those are B&G 100 series. I've just been doing a couple drops but I think I'll wait till next season now to do again. Gotta get those pics still!