# Series vs. Parallel



## SPH (Nov 4, 2008)

I have a job coming up to install 4 commercial hwt's, but they are all put in a corner in an L shape. Normally i pipe them parallel. All with equal distances between. But I am considering running these in series, or a better way of saying it is, "first one in, last one out. 

Any thoughts or suggestions on this?


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## ILPlumber (Jun 17, 2008)

Parallel. Series will run that 1st water heater to an early grave.


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## SPH (Nov 4, 2008)

ILPlumber said:


> Parallel. Series will run that 1st water heater to an early grave.


Well not with reverse return it won't. It will equal out. Same idea as with hydronic heating


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## 422 plumber (Jul 31, 2008)

I would do a series, but also bypassed, so each heater can be taken offline and changed out as needed. I would pipe these in from the top, so you can just disconnect the unions to remove/replace.


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## Ironrod (Mar 28, 2009)

Have you considered doing a three and three. or twinning times three and tie them in . but also cost is a factor.


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