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help with mt hawley boiler model 800-23p

ez3260 Member Posts: 1
I have a mt hawley boiler model# 800-123p and would like to know efficiancy rating of it?


  • Steamhead
    Steamhead Member Posts: 15,519
    edited October 2010
    On an older boiler like that

    it's probably less than 80%, especially if the original oil burner is still in service. From the illustrations I've seen, these boilers look like they were made during the 1940s or 1950s.

    According to the Hydronic Rating Handbook, the 800-123 has a firing rate of 1.10 gallons per hour (GPH) and a net output of 670 square feet of hot-water radiation, or 100,500 BTU per hour. Not great, but I've seen worse. It would do better with a flame-retention burner.

    In the Beacon Boiler Reference which you can see here:


    the Net rating is 615 square feet or 92,250 BTU per hour. Worse, but they might have been using a higher pickup factor when that was published.

    The Gross rating of these boilers is not shown, so we can't calculate their thermal efficiency. If you can find this rating on your boiler, post it and we'll go thru the calc.

    But given the age of this thing, it's probably best to replace it with a modern, efficient unit that will pay for itself. Like this Solaia.

    Where are you located? Perhaps near Peoria, where Mt. Hawley was located?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • billtwocase
    billtwocase Member Posts: 2,385
    Harts Mt

    Is it original, Wayne burner? They were low 70 % at best if still original. I had a lot of them in the area years ago. Glad to see them go. Nightmare to clean, and way over sized. I'd consider updating
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