Side Arm Heat Exchanger or Plate for Domestic Hot Water??

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New Member
Feb 25, 2022
Central Boiler 6048 feeding a 50gal Hot Water Heater for domestic hot water utilizing a side arm heat exchanger dependent on thermal flow and not using a pump or plate exchanger. I posted in February about how I thought I had an air lock but I must have had a mineral deposit or clog in the side arm work its way out because it started working again after being "stuck" for a few weeks. Once I made it through the winter, I decided I would replace it before firing up the OWB this fall......well fall is on it's way! Like I mentioned, I used the same side arm exchanger for 19 years and now I am wondering if I replace it with a fin enhanced sidearm or change over to a plate. During the 19 years that I was happy with the side arm, we raised 3 kids and rarely had hot water has left for college and another leaves next year so I am likely past the greatest hot water demand times. I'm really leaning towards the sidearm again and avoiding the plate which requires the pump. Has anyone had both or switched from one to the other and can tell me why you liked one over the other? Thanks!
Can you plumb it so you can clean it every year?
My plate exchangers have simple boiler drains and ball valves so I can clean them with cleaning vinegar at end of year.
I would replace with what you had, if it worked well for you for that long before. And yes plumb in stops and drains/taps for easy flushing should be done. I haven't heard of a scaled up exchanger unscaling itself before. That part seems odd. Extra ports could also allow for easy bleeding of air out.
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