Indirect hot water - steam boiler

SBoston

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We currently have an old electric hot water heater that needs to be replaced. We have a few options and I wanted to see what the feeling was on the wall.

We have a Burnham steam boiler that was installed last year that we could tap off of and install an indirect hot water heater, we can install a stand alone unit or install a new electric.

We have had a few installers come to the house each with very differing onions. The fist guy told us that it's very inefficient to have an indirect hot water tank off our boiler because the system has to bring the boiler water up to temp then transmit that to the indirect hot water tank also my boiler running at 84% efficiency can easily be surpassed by a standalone unit. He suggested either a power vent tankless or high efficacy tank unit.

Another installer completely disagreed with the first guy and suggested adding the hot water loop off the boiler and using an indirect super store.

The last installer suggested staying with electric and replacing it with a newer model stating the electric seems to work and the cost of switching to gas or indirect will never be made up with the savings.

All are local pro's so I could go either way</span>

Al Roethlisberger

Interesting, I wonder how much location matters....

This is an interesting question I've wondered about at times as well, knowing that my 20 year old boiler will probably need replacing sometime from tomorrow to 10 years from now as it was so sorely mistreated for all of its life(no protection) that I'm sure its days are numbered.   And I've wondered if indirect DHW might be an option to consider when that day comes.



But I would think that location, and consequentially number of heating days, might play a part in making it economical or not.  In your case, I assume you are in Boston, I would think your climate would lean toward more economy than say mine in North Carolina where firing the entire boiler *just* to maintain DHW for 8 months of the year may not make sense??



Plus your feedback on high efficiency instant or even dedicated tank heaters is interesting.  So I'll be interested to hear what people think.



Al

 

Steamhead

I'd go with the indirect

Typically, switching to a tankless requires upgrading the electric or gas input, since these units must heat the water in real time. This requires much larger burners or elements than a storage-type unit. Also, most gas-fired tankless units cannot use a standard chimney, so you'll have to find some other way to exhaust them. This can be a problem in older buildings with lots of windows and little snow-line clearance.



The main advantage of the indirect over an electric tank-type heater is that the indirect has much more heat-transfer surface than the electric, so it will produce more hot water for less fuel input.

David Sutton_6

Got to agree with frank !

David

Charlie from wmass

How much hot water do you use?

I like the idea of the indirect because it keeps the boiler exercised during the summer. I also have told many folks who are on a tight budget to stay with the electric water heater. It is not always cost effective to go with an indirect.