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Buffer tank

I suppose it cannot hurt, but that was not really your question.

Personally, I do not see buffer tanks as an absolute "must-have". Rather, they are installed to help mitigate a problem. If the problem is short-cycling, there is an advantage.

I guess hearing my dad's voice, saying "if it's not broken, don't fix it" applies here.


  • Mike Dunn
    Mike Dunn Member Posts: 189
    buffer tanks

    Is using a buffer tank on a waste oil boiler considered good design? Is it correct to try and run the boiler for longer periods of time via the buffer tank, or is the buffer tank more of a luxury item that has a few advantages but not enough to warrant using one in every install?
  • hot_rod
    hot_rod Member Posts: 14,552
    Depends on the style of boiler

    I find buffers are a must on the coil tube design like Clean Burn. Even with a constant load they need to dump that 10 minute post purge heat somewhere. Else they trip that high limit constantly :)

    I've gone back and put mine on constant circ thru the boiler. WQhen the start to ash up they really overshoot after burner off cycle.

    As`for other brands, cast iron blocks for example, a lot would depend on the loads. If they are multi zoned, and especially with micro zones it would be wise to buffer them.

    The buffer makes an excellent de-coupler and a great spot to VS injection mix from.

    Depending on the boiler you might run as high as a 40 delta tee and pipe them with small diameter tube.

    Reverse indirects are an excellent way to buffer if you have enough DHW load. May as well put that hot buffer to work with a second job.

    Think long and hard about waste oil in general. They are incrediably messy to service and keep clean. Dirty diesel waste oil really builds ash quickly.

    Wear appropiate gear when servicing, like a listet respirator!

    hot rod
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
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