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Keystoker KAA-4-1 coal stoker boiler

leonz Member Posts: 392
edited August 2015 in THE MAIN WALL
As a new member of the forum I can say that I am the proud owner of
the texts Classic Hydronics and Pumping Away.

I am in the planning stages of a 2 boiler replacement(hand fired wood and coal
and Buderus Logana G205 with my third Reillo burner(GRRRR) used for back up heating)
with a dual fuel keystoker KAA-4-1 coal stoker 120,000 BTU using the tile lined block chimney I have.
I will be reusing the same Reillo burner and I will be bringing the RACOR 500FG fuel filter inside and
mounting it near the boiler.

This eliminates the entire rats nest of plumbing I have. I will be installing
a steel expansion tank and airtrol fitting BACK into the system.

I have attached the file containing the plumbing diagram and manual.

I have a very long 225 feet single loop system heating load 3/4 finned baseboard which
is also the dump zone.

I will be replacing the two pump system used for the heating loop/dump zone temperature balancing
loops with one pump using 4 GPM as i will no longer need the second pump.

By using the boiler bypass loop I expect to use much less coal as the new unit will burn 11 pounds
an hour at the low setting and even less to maintain an idle fire bed before heat calls.

I have learned a lot from the 2 books I mentioned and I candidly wish I had a
standard radiator set up or a one pipe steam system (I grew up in a steam heated home).

I cannot upload the better drawing because adobe says it was corruppted but I hope
the manual and its drawings are enought to provide for the discussion.

The Keystoker boilers are using the Hydrostat 3250 now as the Honeywell units are no longer
made. I would love to hear anyones experience with them in any application.

My main issues are brown outs, voltage spikes and power loss with our utilities 4,000 Volt single phase
power distribution system the year round and I want to be able to use my generator to power
the heating system as needed by simply plugging in the power leads from the boilers
combined stoker and fan motor and the hydrostat into a common three-five gang
receptacle that will be fed from the 150 Ampere service using BX cable with 50 amp disconnect
breaker to allow me to use the generator when needed. I will need the extra recepticle
for an incandecent work light to keep the boiler interior warm and dry in the off season
as I will not be using the boiler the year round.

My computer is very old and I am not proficient with it and I ask for your patience.
and I would rather to it right the first time.

Thanks much



  • leonz
    leonz Member Posts: 392

    None of you are using the Hydrolevel brand???

  • Robert_25
    Robert_25 Member Posts: 299
    The Hydrolevel controls work fine. If you intend to use the economy feature of the 3250 it will take some trial and error to get the boiler to behave the way you want. Due to the slow response of your coal boiler I would start with the economy setting on #1 or 2 and see how it does.

    Also, if you intend to use the low water cutoff feature of this control you will need to install the "electrowell" made by Hydrolevel. The well will need to be removed and cleaned about every 3 years, otherwise it may falsely sense a low water condition.
  • leonz
    leonz Member Posts: 392
    Hello Robert,

    Thanks for the comment about and the information about the the Hydrolevel 3250.

    They are shipping them from Keystoker with the electrowell to replace the Honeywell triple aqaustat that was installed in the side of the boilers.

    I am still up in the air about whether I should buy the dual fuel
    unit and eliminate the oil only boiler-it may have just 2,000 hours use in 27 years as a back up unit.

  • Robert_25
    Robert_25 Member Posts: 299
    Leaving the oil boiler may have some benefits for resale, and it can be setup for an automatic backup. If neither of those interest you, yank it out.
  • leonz
    leonz Member Posts: 392
    Thanks again Robert for the comments.
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