On Mar 21, 10:16*pm, Aaron FIsher wrote:
I realize two major mistakes of my last post on this topic:
- How would you set up two 50 gallon hot water heaters in series?

My mistakes were that I confused everyone by mixing series and parallel
(they're clearly hooked up in series); and I didn't mention the
particulars.

The particulars (AFAIK) a
- Well pumps cold water out of the ground
- It goes to 10,000 gallon storage tanks
- It then goes to a pressure pump & 40-gallon (approx) blue tank
- It then goes to the FIRST propane 50 gallon hot water heater at about
135 degrees
- The output of that first hot water heater goes to the input of the
second (exact same duplicate unit) hot water heater set to the same
temperature
- The output of that second hot water heater goes to the house but there
is a small grinder-sized hot water recirculating pump in the mix on the
final output

From reading this web site:http://www.chinawinds.co.uk/diy_tips...s_and_parallel...

I find that serial connections:
- Often use non-identical hot water heaters (mine are identical)
- The second heater does almost no work
- All the work is done by the first heater

They don't say "WHY" you'd want this (if both tanks are identical).

They did say that it happens when a house is expanded and this house WAS
expanded (they added two bathrooms and a maid's kitchen).

But, it seems to me it SHOULD have been done in parallel (to have more
water). Weird, but the web site gives no advantages to serial connections!

They say the parallel connection delivers more hot water than the serial
connection. So, I'm REALLY confused now why anyone would design a system
with two series hot water heaters that are identical.

The 1st is a "water heater"...the 2nd is a "hot-water heater".