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What do you think of the Heat-Flo HF40 water heater?

Hi folks -- My family just moved into a new 4-bedroom, 2-story colonial near Boston and need to replace our hot water heater. Our new plumber has recommended the 40 gallon stainless steel Heat-Flo HF40 indirect water heater. I can't find much information about it online, and our plumber suggested I ask here.

What do you think of this company and water heater? If you've used it, what's been your personal experience? Would you recommend it to us? Why or why not? All feedback and links to online resources are welcome and appreciated!

Thank you -
Andy S.


  • solradman
    solradman Member Posts: 53
    the HeatFlo HF40 is a 40 gallon indirect water heater. It needs to be teamed with a boiler. Make sure the 40 gallon will meet your needs, ie. will it produce all the hot water you need. Heat Flo makes good stuff.
  • andysaks
    andysaks Member Posts: 12
    Thank you for the feedback Solradman. A 155,000 BTU Lochinvar knight KHN155 gas fired boiler will be installed alongside the water heater. (I'm asking for feedback on the boiler on a separate thread.)

    How do we know if the 40-gallon will meet our needs? There are only two adults and one child in the house, so I imagine our hot water needs are relatively small, yes?
  • Zman
    Zman Member Posts: 6,989
    Heat flo makes a nice product.
    Don't get sucked into thinking only one boiler will work with the indirect. The manufacture provides some capacity data when "teamed" with certain boilers. It is not a requirement, you just have to do a little math to be sure it will work.
    As mentioned in your other thread, the boiler sizing seems way off. Don't get sucked into the bigger is better mentality. You wouldn't purchase a 1 ton truck to haul groceries, don't buy a miss sized boiler.
    Post some more info about your system and we can provide more sizing help.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • andysaks
    andysaks Member Posts: 12
    Hi Zman,

    Thank you for your feedback. Feedback from my boiler thread shows everyone agreeing we should get an 085 boiler instead of the 155, so let's assume for the moment we do.

    What other info about our system would you like? Happy to share anything helpful.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,307
    Heat Flo has great products made right here in new England. I have installed a few, and have one in my own home.

    Personal favorite is the solar tank with electric backup. Here in heating oil country, in the summer it is much more economical to turn off an oil boiler and just use the electric for summer hot water. With a low mass mod/con gas boiler not as much an issue.

    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Zman
    Zman Member Posts: 6,989
    I think you have provided most of the needed info on the other thread. Unless you have a very large tub that you need to fill quickly, the 085 with the 40 gallon tank sounds perfect.

    Sometimes you can convince the installer to go with a smaller size if you provide them a formal scope in writing. Be sure to include some language that insists on the installation to be per installation manual unless alternate is approved in writing.
    This let's them off the hook if it is undersized (it won't be).
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein