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commercial duel fuel conversion NYC

Happy New Year all,

I was thinking about converting to a duel fuel solution for a building we manage in NYC.

The building is a 24 apt that is currently getting heat and hot water from a 1680000btu FST 40 boiler with a carlin 701 CRD burner.

Thanks to everyone's help and input I have made huge progress in updating the building with installing 11 gorton #2s, installing missing insulation and installing a vaporstat to control the High/Low burner feature that was never utilized in over 15 years. Now the whole building heats evenly with just under 1PSI when it used to cut out at 2.5 PSI.

Now I wanted to come to you again for some more advise/input. Last year before my upgrade I burned just over 13K gallons of fuel. I suspect with my upgrades and what I have seen so far I was able to cut at least a thousand gallons on average. This still amounts to over $30K for fuel. I have just converted a smaller 6 unit building to gas and saw astronomical saving. I was thinking of going to duel fuel option for this building and wanted to know if anyone has done it before and if it was worthwhile.

Is there a big benefit to separate the hot water from the big boiler into 2 seperate 100 gallon water heaters?

Is it easy to switch back and forth between oil/gas settings?

Thanks in advance!


  • Tim McElwain
    Tim McElwain Member Posts: 4,628
    I have commisioned

    several dual fuel burners in recent years using Power Flame Dual fuel burners. I have seen a savings on one system of 21% actual fuel usage calculations done.

    The other system was in a church (steam system two zones with HB Smith boiler) so it is not running like a building that is occupied. They however had a savings of 30% compared to previous oil bills The oil bill the year before conversion was $20,000 this past year it was around $14,000 with gas being used all the time.

    Yes with a modern power burner such as Power Flame or others it is simply changing a switch on the burner.
  • Mike Kusiak_2
    Mike Kusiak_2 Member Posts: 604
    Dual fuel burners

    Dual fuel is definitely the way to go. I am responsible for the operation of three FST-80 boilers in an apartment complex in NY and all three have dual fuel burners.

    Aside from the obvious difference in fuel price there are other advantages. If you are capable of dual fuel operation, ConEd can give you a special discount on what is called interruptible service. This means that when they are short on gas, they will notify you to temporarily switch to oil. In return you pay a significantly lower rate on their delivery charges. Last year we ran on oil for only one day and this year not at all so far.

    Gas is also much cleaner burning and requires minimal if any cleaning of the boiler tubes at annual maintenance time.

    As Tim mentioned, switching fuels is just a matter of flipping a switch. If there is a problem with the gas side of the burner you may be able to switch to oil and vice versa. There is a common blower and controls, but if the gas train has a problem the oil pumps are pretty much independent and remain operational.

    We do not use the boilers for hot water, but use two parallel tank type gas heaters in each boiler room. Much better in the summer when you don't have to keep those big boilers hot all season long.
  • Haviara
    Haviara Posts: 30
    gas heaters

    Thanks for the input!

    I am defiantly going to look into interruptible service for the building. I hope to be able to muster the cash or finance the conversion as I understand it can be a pricey process.

    In our early discussion the contractor had recommended two parallel tank type gas heaters at 100 gallons each. I was concerned that this might not be enough during peak usage as the building has a large number of apts with children. Do you think 2 x 100 gallons would be sufficient for a 24 unit building with above average usage?
This discussion has been closed.