Converting a Steam Boiler to Hot Water
Converting a Steam Boiler to Hot Water
(OP)
A contractor just submitted a proposal saying that he can convert our 2-year-old cast iron sectional steam boiler into a hot water heating boiler.
Is this procedure possible and safe?
Thank you for any help.
Is this procedure possible and safe?
Thank you for any help.





RE: Converting a Steam Boiler to Hot Water
It sounds like it could be possible to convert a steam heating boiler to a hot water heating boiler.
Is it safe? Well, I would carefully review the contractors proposal in detail (what specific modifications are being proposed to the current boiler in terms of changes to operating pressure and temperature, burner configuration, output of hot water, storage tank, what standards or code have they referenced regarding the modifications, etc) and most important their engineering credentials and experience. I don't have a copy of ASME Section IV Rules for Construction of Heating Boilers to review at this time.
RE: Converting a Steam Boiler to Hot Water
I apologize for being vague originally.
The boiler in question is for a commercial heating system.
I am comfortable with the exterior aspect of such a switch, as I can redesign the piping and tanks etc as required, however my knowledge on the internal workings of boilers is poor.
To be more specific:
If the operating pressure of the new hot water system falls within the acceptable operating pressures of the steam boiler, are there any other reasons internal to the boiler that would make this switch a bad idea?
RE: Converting a Steam Boiler to Hot Water
RE: Converting a Steam Boiler to Hot Water
RE: Converting a Steam Boiler to Hot Water
It has been two years since this replacement, and the water situation has reportedly gotten worst, to the point where to keep conductivity under control 4 blow downs per day are required.
My initial reaction is the system must be leaking like crazy somewhere to require enough feed water to raise the conductivity so fast, however the building operators indicate this is not the case and the water is just that bad.
I am going to inspect the system next week to check on this.
Given all of the above, the conversion question was raised as being a possible solution.
Personally I would like to see the system fixed rather than a conversion, but if the water is that bad and if the operators push enough for it, the conversion will happen.
Altering the rads and piping I can handle, it is just the actual boiler part I an not familiar with.
RE: Converting a Steam Boiler to Hot Water
Make sure you do not have a problem with condensing flue gas. The steam boiler was not designed to accommodate condensing flue gases. If cooler boiler supply water is introduced with a lower operating temperature, condensates from the flue gas may be an issue.
RE: Converting a Steam Boiler to Hot Water
Check your rads - not all steam rads lend themselves to being converted to hot water.
RE: Converting a Steam Boiler to Hot Water
RE: Converting a Steam Boiler to Hot Water
to change to water the level controls have to be raised to the meassure the llco to the top.
it is important that the llc-off are not disconnected at all; most states now require llc-off on all water boilers, thermosthats for oper. and hi-limits have to be added to control temperature, conrtrols for heating can be low temp to 140 deg F so 180 deg max. controllers are limits.
the contyractor have to be familiar with the ANSI Stds as well as ASME CSD-1 controls for water boilers.
It can be done but if not done correctly can be dangerous.
Hope this helps.
GB
RE: Converting a Steam Boiler to Hot Water
RE: Converting a Steam Boiler to Hot Water
I was unaware of the boiler stamp indicating if a boiler could handle hot water as well as steam. I will be sure to check that out.
RE: Converting a Steam Boiler to Hot Water