Click here to Find a Contractor in your area.
In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Need to contact us? Visit

how should I prepare the system for summer?

i'm new to steam, and this is my first year using it.  so is there something i should do to 'summerize' the system?  do i drain the boiler?  shut it off? change the tires?  thanks in advance for your help.


  • FredFred Member Posts: 5,218
    edited April 2014
    Prepare for next heating season

    You don't have to do anything to prepare you system for summer. But use the warm months to repair any known leaks, check the gaskets at the top and bottom of your sight glass, clean the burners and fire box, have a pro adjust your pilot (if you have a standing pilot) and maybe do a combustion analysis/adjustment if it hasn't been done in the past few years. Take the pigtail(s) off from under your Pressuretrol/vaporstat and gauges and clean them out and re-install. Walk your basement and check the mains for any sagging pipe or anything that doesn't look right. Before the end of this heating season, check to make sure your main vents and radiator vents are working properly and replace those that need to be replaced. As we get closer to the next heating season, if you need to clean and flush out the wet returns and the boiler, do so just before you fire the boiler for the first time next season so that you can run the boiler for 15 to 30 minutes to burn off excess oxygen. If you have a standing pilot, I leave mine on during the summer to keep things nice and dry. If you have a float type LWCO, it should be cleaned and flushed out. Again check it before the end of the heating season and blow it down while the boiler is actually running. If it is working properly, it should shut your boiler down while you are holding the blow-down valve open and the boiler should start back up when you close the blow-down valve. 

    Sounds like a lot but it's 3 or 4 hours of work to ensure comfort next season.

    Some guys like to flood their boiler at the end of the season so as to prevent rust/rot at the normal water line but I don't think many people do that and I really doubt that it adds any significant value/life to the boiler, but that's only my opinion.
  • nicholas bonham-carternicholas bonham-carter Member Posts: 6,535
    Well said Fred

    Agreed with your well described procedures.

    Anyway we love our steam boilers and systems, so love to make them last by these simple procedures.--NBC
  • ChrisJChrisJ Member Posts: 8,594

    I've wanted to flood my boiler for summer shutdown except I could never figure out how to boiler the water after doing so and never found clear instructions on doing this.

    The last thing you want to do is leave a ton of fresh water laying in it for months.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment

    Steam system pictures
    Central air project pictures
  • JStarJStar Member Posts: 2,668

    I like the idea of flooding the boiler. Nearly 75% of the leaking boilers we find are rotted out right at the waterline. I would rather replace a riser pipe than a boiler every 10 years. If you drain it completely, you'll have to add a dessicant inside the boiler or completely hand-dry the inside. Both options are impossible or implausible.

    When you flood the boiler, let it run until it starts to make a terrible surging sound. That'll be hot enough to boil the O2 out.
    - Joe Starosielec
    [email protected]
  • My thoughts

    You really want to do all the cleaning before the summer because if you let any debris lay in the bottom of the boiler or pipes all summer, it will tend to harden.  I'd do a complete flushing out and cleaning of the boiler return lines and controls. If you have used system cleaning chemicals or treatment in the past, you may want to add a heavy dosage of oxygen scavenging chemical to the boiler water, then overfill into the risers and boil as described above to remove the initial oxygen.  If you do want to clean your system and boiler with cleaner, now would be the time to do it, then lay it up.
    The Steam Whisperer (Formerly Boilerpro)

    Chicago's Steam Heating Expert

    Noisy Radiators are a Cry for Help
  • FredFred Member Posts: 5,218

    I think not
  • Mark NMark N Member Posts: 1,035
    edited April 2014
    Tankless Coil

    You should have no issues raising the water level in the boiler to cover the tankless coil during the summer. The aquastat will turn off the boiler at whatever you have it set to. You will most likely have better hot water during the summer having the coil underwater. Remember to lower the water before the heating season next fall.
  • FredFred Member Posts: 5,218
    edited April 2014
    Is that really practical?

    Isn't he going to significantly increase his fuel cost to operate that tank-less? I would think the extra energy used to heat/maintain temp of the additional water in that boiler would likely make the tankless approach senseless from an energy savings perspective?? I guess one has to calculate the additional fuel consumption over the expected life of the boiler and compare that to the additional life flooding may add to the boiler.

    Maybe this discussion should be on a new thread. The goal here was to help a new steam owner prepare his system for the summer/next season.
  • ChrisJChrisJ Member Posts: 8,594
    edited April 2014

    Why would flooding the boiler cause more energy usage for a tankless? The exposed surface area of the boiler doesn't change and the increased water only means it would hold heat longer due to the added mass. This means the burner runs longer, but it also stays off longer.

    If anything it increases heat transfer to the tankless coil meaning he could theoretically lower his aquastat temperature which would decrease how much heat the boiler is losing to the surrounding area. It should also increase the amount of heat pulled into the water from the burner because water is touching more areas of the block. This is why any boilers that are used for both steam and hot water always have higher AFUE ratings for hot water.

    Flooding a boiler with a tankless coil is a win win in my opinion and I think Burnham even recommended it in the book I had for my V83 boiler.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment

    Steam system pictures
    Central air project pictures
  • FredFred Member Posts: 5,218

    I guess the efficiency is dependant on how much longer the burner runs compared to how many fewer cycles it has to run. As I said in my earlier email it needs a calculation. I'm not sure which Burnham book you might be referring to and what set of circumstances they might have used but I'm not sure I'd buy what they say without doing my own "experimenting", in my own environment. Clearly their are questions, pro and con, on this subject. Maybe someone on this Wall has experience doing that and can share what they have learned.
  • Mark NMark N Member Posts: 1,035
    Tankless Coil

    A tankless coil is the least efficient way to make hot water. By raising the water level you put the entire coil under water increasing the heat transfer surface in the summer. An indirect or a separate hot water heater would be more efficient.
  • Chris_LChris_L Member Posts: 73
    Flooding with blowdown water?

    I am not sure I want to try running my boilers while they are flooded.  Is there any reason why I couldn't take out some extra (clean) blowdown water near the end of the season, seal it in a bottle and use that to flood the boiler (through a T at the safety relief valve) when I shut it off for the season?

    The blowdown will have been doxygenated through use and have some steamaster tablets already dissolved in it.  My boilers are small so I only need a gallon or so each, and I figure I'll be better able to tell how much water I am adding this way.

    (No tankless coils; these boilers will be completely shut down.)
  • FredFred Member Posts: 5,218
    That woulld be great

    That would be a great test to determine how much benefit is actually recieved by covering the tank-less coil versus keeping the water at its normal level, at least in terms of cycle duration and fuel usage in a real world environment (as long as consumption remains relatively flat, unless you have a way of measuring fuel usage on a per cycle basis). Thanks! 
  • outatune13outatune13 Member Posts: 12
    summerizing the steam system

    thanks so much. very informative.  this is my first time with steam, i'm learning a lot from everyone here.  Cheers, Jay
Sign In or Register to comment.


It looks like you're new here. If you want to get involved, click one of these buttons!