Multiple Water Heater Hook Up

Discussion in 'Water Heater Forum, Tanks' started by dripdrop, Nov 28, 2012.

  1. dripdrop

    dripdrop New Member

    Messages:
    3
    Location:
    Ohio
    hi. i have a commercial establishment that requires additional BTU's.

    my plumber has the following design:
    - use 2 water heaters; 40 gallon & 65 gallon
    - each water heater to service 2 different "zones"
    - main water line comes in and 'T's' off to each water heater
    - hot and cold water supply lines from 40 gallon water heater goes to zone 1
    - hot and cold water supply lines from 65 gallon water heater goes to zone 2

    please review diagram attached and let me know if this is a feasible solution.
    thanks again!

    Attached Files:

  2. Towers Plumbing

    Towers Plumbing In the Trades

    Messages:
    19
    Location:
    Salt Lake City, UT
    Not sure what your distances are but you might consider a 50G 50K BTU or 60/60 to do the same job. Bradford makes a 55 gallon 80k BTU heater that has a 200 gallon for first hour delivery rating. Heaters are more but still might be less than two water heaters and repiping.
  3. dripdrop

    dripdrop New Member

    Messages:
    3
    Location:
    Ohio
    thanks for the reply towers.

    i actually have all the material onsite. i'm more concerned with the design illustrated in my original post. will this design work?
    thanks again!
  4. leejosepho

    leejosepho DIY scratch-pad engineer

    Each zone should get hot water if the line supplying the heaters is sufficient and if the main line that also supplies cold water to each zone is sufficient. But in my own case, our water heater is somehow the last to be supplied and we end up with little hot water in the bathroom whenever water is being demanded anywhere else.
  5. dripdrop

    dripdrop New Member

    Messages:
    3
    Location:
    Ohio
    so will the design i have in the drawing work and pass code?
  6. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,641
    Location:
    Cave Creek, Arizona
    It is a "no brainer". Give BOTH zones the maximum BTUs. Connect the two zones together, then pipe the cold water into one of the heaters, it is immaterial which one, then the hot of that heater to the inlet of the other one, and finally the outlet of that heater to the connection to both zones. This way you do not have to worry about either zone needing more hot water than ITS heater could supply. The only possible downside, is that if the zones require different water temperatures, then you use a temperature control mixing valve on the zone requiring lower temperatures.
  7. MACPLUMB 777

    MACPLUMB 777 TROJAN WORLDWIDE SALES RP

    Messages:
    679
    Location:
    Houston, Texas, United States
    Take HJ'S plan but use the same size water heaters and plumb them both cold water in
    and hot water out this gives you maximum btu's and tank storage plus if one goes down
    you can bypass it and still get by on the other heater
    this is per ALL Mfg's install specifications !
    PHD IN WATER HEATEROLGY
    LICENSED SERVICE AGENT FOR ALL BRANDS
  8. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,641
    Location:
    Cave Creek, Arizona
    In "parallel" works as long as you can convince the cold water to flow through both of them equally. That ONLY happens when the flow rate is high enough so that it has to flow through both. In "series" the water ALWAYS has to flow through both and it makes no difference if the heaters are the same or not. Two ball valves and two "3 way valves" can isolate series heaters, (Doing it with parallel installations requires four ball valves), and the first one will usually fail first so you make it the cheapest one of the pair. With parallel, when one fails, the replacement will NEVER have the same dynamics as the remaining heater so it will disrupt the supposed equal flow, unless you replace both of them at the same time.
Similar Threads: Multiple Water
Forum Title Date
Water Heater Forum, Tanks Multiple Hot Water Heaters Jan 29, 2012
Water Heater Forum, Tanks Multiple problems with water heater(maybe)? Jan 18, 2012
Water Heater Forum, Tanks reliance 606 propane water heater Tuesday at 6:41 AM
Water Heater Forum, Tanks Cap blown off top of electric water heater Sep 2, 2014
Water Heater Forum, Tanks GE Power Vent Water Heater Diagnostic codes Aug 31, 2014

Share This Page