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Boiler Cycle

Now that the boiler is all working again, I was wondering what the normal cycle of the boiler is supposed to be? Right now, i call for heat, all Rads get steam and heat up pretty quick. Probably with 10 - 15 min cold start boiler to hot Rads. the pressure of the system starts to pick up and in about 20 min, I hit 5 PSI and the pressuretrol kicks in a shuts her down. After about 2 minutes, the pressure comes down enough and the boiler kicks back on for about 5 min before it hits the 5 PSI again.

I'm positive that this boiler is oversized. Few things happened to lead to this. First, Plumber that had no idea what he was doing. Replaced an oil fired Weil for this Gas fired IN6. He never actually did the calculations, just looked at the old oil fired and replaced with the same load.

In addition, dealt with an idiot of a contractor during my kitchen renovation in which he just removed two rads and didnt replace them with anything.

Right now, whole house has 6 Rads on an IN6. I'm sure this is not sized properly. Someone told me that an IN6 can handle 11 rads or so.

I'm just wondering how bad of a spot im in right now.


  • adambnycadambnyc Member Posts: 260
    you've certainly got my attention. good/bad of this? how would i go about setting this up? Is there another thread or more information that you could point me to?
  • adambnycadambnyc Member Posts: 260
    Thinking maybe i shouldnt monkey with this one myself too much. Anyone around North Jersey that has experience doing this?
  • SteamheadSteamhead Member Posts: 13,774
    Put the missing rads back and see how you make out. And crank the pressure down- you don't need 5 pounds on that system.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • adambnycadambnyc Member Posts: 260
    I cant put the missing Rads back, renovation removed the places they used to be in. Unless i feel like heating my outside enclosed porch just for the heck of it.
  • SteamheadSteamhead Member Posts: 13,774
    They still make radiators in different shapes and sizes. You should be able to find a place for at least one.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • delta Tdelta T Member Posts: 809
    We would need to know what is called the EDR (Equivalent Direct Radiation) for all the rads to answer whether it is oversized or not, if the installing contractor did not do this it likely is, especially if two rads were removed. On a steam system the heat loss does not matter as much as the size of the radiators for boiler sizing. especially if two rads were removed there is a good chance it is now oversized for your system. The number of radiators is irrelevant, its the total square footage of the radiators that matters. Take some good pics of your rads, measure the height of each, and we can help you size them.

    Your boiler (at sea level, if you are above 2000 feet you will need to de-rate the output by 4% per 1000 feet you are above sea level) should support 450 sq ft. of steam (assuming a 25% pickup factor for piping which may or may not be necessary depending on how well your piping is insulated) which means that on average for 6 rads you would have 75 sq ft radiators. That would be a very large radiator. It is most likely oversized by a fair margin, as was the old one even with the other two rads. Again, we would need to know the EDR to tell you for sure.

    The other thing is that you should not be running 5 PSI. That is far too high. A pressuretrol in my opinion is good as a high limit safety, but I much prefer a vaporstat for actual boiler control as it will allow you to set much lower pressures accurately and thus save on fuel consumption. Pressuretrols are only good down to about 1 PSI before they start to not sense accurately, whereas vaporstats allow control on a scale of ounces. A properly installed system can run on 8 oz (or less) just fine. Vaporstats cost more than pressurtrols.

    If it is oversized short cycling is not going to go away and if nothing else is done, will get worse with the installation of a vaporstat and lower pressure settings.

    Shortcycling will shorten the life of the boiler and associated controls, increase the amount of maintenance, and decrease overall efficiency. Depending on how oversized it is, it may be worth fixing the problem now and saving your self the headaches later IMHO.
  • delta Tdelta T Member Posts: 809
    Wow so many people commented as I was writing this..... :)

    I second the 2 stage gas valve, probably your best option.
  • KC_JonesKC_Jones Member Posts: 4,401
    Just a point of clarification so everyone understands. You currently have a remodeled kitchen with no heat? They removed the rads and didn't give you any heat to replace them?

    As far as your EDR, do a google search for calculators. There are plenty out there and I believe most of the major boiler manufacturers have them on their website. Here is just one starts at the bottom of page 9:
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • adambnycadambnyc Member Posts: 260
    thats accurate KC. Walls came down and i was told "the air would circulate". I fired that contractor and would be suing him if he actually had anything to sue for.

    I'd like to upgrade the size of the radiators on the first floor of the house as, that floor struggles to keep warm while the second floor swelters.
  • adambnycadambnyc Member Posts: 260
    I was thinking of putting in kickplate electric heaters under the kitchen cabinets.
  • delta Tdelta T Member Posts: 809
    Is this a one or two pipe steam system?
  • adambnycadambnyc Member Posts: 260
    one pipe
  • delta Tdelta T Member Posts: 809
    The difference could just be the rads in the kitchen, or it could be a venting issue, traps not working correctly.....

    Where are you located?
  • adambnycadambnyc Member Posts: 260
    North Jersey, Teaneck
  • EzzyTEzzyT Member Posts: 969
    @adambnyc private message me and we'll talk
    Creative Solutions Plumbing & Heating LLC
    Lic #12683
    Co-Owners: Fred Drescher, Jr & Eliezer "Ezzy" Travis
    Marketing & Operations: Dawn Drescher
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    Check us out on Instagram: creative_solutions519
  • adambnycadambnyc Member Posts: 260
    Follow up question on this. Had the 2 stage done, great upgrade! The boiler fires and pretty quickly builds to the down fire pressure. I think if I had better venting, I might stay on high fire a bit longer.

    I was curious about upgrading the venting. I have two main vents, 2x maid o mist #1's. I was thinking about replacing with big mouth vents. I don't think anyone will disagree with this upgrade

    I also want to increase the venting at all the rads. Is this a bad idea? Currently the first floor as smaller vents and the second floor has larger on the rads. I want to increase the venting on the first floor to be the same size as second floor.
  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,127
    Wait until you have the improved main vents in place before doing anything to the radiator vents.--NBC
  • Jamie HallJamie Hall Member Posts: 12,721
    And be a bit cautious about making the first floor vents bigger -- you may unbalance the two floors that way...
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • FredFred Member Posts: 8,418
    There is likely much less air (shorter run-outs and verticals) to expel from the first floor than there is for the second floor. Making the vents larger on the first floor may well cause steam to hit the first floor rads much quicker than the second floor. Ideally, you want steam to get to each rad at about the same time. Do upgrade your main venting though.
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