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boiler drained .vs. staying filled

Charles G.
Charles G. Member Posts: 113
Why not just do all the work at one time--in the fall?


  • michael_4
    michael_4 Member Posts: 28
    boiler drain vs staying filled

    My client would like to drain his boiler this summer and leave it unfilled for the season. While it is empty we are going to make some small reairs. Then just before fall do some major modifications with several zones and refill it then. Is there a problem with leaving the boiler empty for the summer? I know fresh water will corrode, but I figured an empty boiler would be fine. Thanks -Michael
  • ray hickethier
    ray hickethier Member Posts: 26

    Don`t drain the boiler any more than you have to to make necessary repairs! Fresh water is very corrosive to the system (new minerals and oxygen) and should only be added as needed! Also gaskets may dry out and the boiler may leak on a refill.
  • Dale
    Dale Member Posts: 1,317
    lay up

    Interesting question, I agree on the leave it filled comment. You don't want any gunk inside drying hard. On large boilers the mfgs. have "lay up" instructions to follow which involve putting in a dessicant. Burnham has good general instructions for this if you choose to do it.
  • Glenn Sossin_2
    Glenn Sossin_2 Member Posts: 592
    My thought - Don't Drain

    It seems logical to me that besides adding contaminants from fresh water, you are adding alot of new free O2 in the air that replaces the water. It will rust the system as well.

    After a while, the water in the heating system becomes chemically cooked - that is to say it's predominantly inert. Any corrosive agents and free O2 have been consumed in chemical reactions over the previous periods the boiler has been firing. The introduction of new water or new air, simply adds a new O2 and a batch of new potential chemical reactions to occur - namely rust.
  • michael_4
    michael_4 Member Posts: 28

    The point of view from the gaskets drying and gunk hardening is enough for me to convince him. It is a Raypak boiler. The work that needs to be done(in next two weeks) we cannot isolate; so we will drain down,repair and refill. Come fall we will drain down, do the renovation part and refill again. Thanks for the replies. -Michael
  • michael_4
    michael_4 Member Posts: 28

    Client has his childs bedroom that is to be remodeled/renovated now and we need to remove a radiator for the bump out. Thanks -Michael
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