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Water Pressure Loss Indirect versus Rheem Power Vent & Install Questions

rsc92 Member Posts: 51
So it is getting to be time to replace a 15+ year old Rheem Power Vent (75 Gallon) Hot Water Heater.  Our domestic HW is somewhat rusty and I am told that is an early warning sign that the unit is beginning to fail (true?). We drained the tank and that only seemed to make matters worse.

Anyway, 2 different plumbers have recommended that I pair a Burnham Alliance Stone Lined Indirect with my Rheem PVG-6.  We live on Long Island (NY).

Presently, our 75 gallon Rheem Power Vent is marginally sufficient.  Both plumbers told me that a 50 gallon indirect will deliver more hot water than the Rheem did.  Do you all agree?  Should I just get the 70 gallon indirect (about $300 more).

If I go with the Alliance Indirect instead of another Rheem Power Vent will we notice any difference in water pressure (while showering, etc)?

One plumber said he would use an existing circulator and add a zone valve to handle the indirect tank.  The other plumber said he would add an additional circulator just for the indirect tank.  Thoughts on which is the better way to go?  The circulator that the first plumber was going to pair with a zone valve already handles 2 fan coils (each has its own zone valve).

Finally, if it was your setup, would you go with the indirect or another Rheem Power Vent HW heater? 

An on demand (Rinnai, etc.) is not an option because I fear we will lose too much water pressure when 2-3 showers are running simultaneously.

Thanks to everyone for your input.  Greatly appreciated!


  • Zman
    Zman Member Posts: 7,588

    How many Btu's does your water heater put out?

    How many Btu's is your boiler?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • rsc92
    rsc92 Member Posts: 51

    HW Heater - Approx 90,000

    Boiler -Approx 165,000
  • Snowmelt
    Snowmelt Member Posts: 1,418

    This IMO I always tell customers to go with an indirect water heater if you to to

    Taco hvac.com

    There's a little section with webinars I would view that, there educational.

    There's no extra flame so your only running the boiler, you put that on priority and your good.

    Make sure you have at least 1 inch piping to indirect water.

    As far as pressure it doesn't matter.
  • rsc92
    rsc92 Member Posts: 51
    Circulator or zone valve

    Which is better? Should the indirect have its own circulator or is a zone valve fine?
  • icesailor
    icesailor Member Posts: 7,265

    Its been my long experience to always give customers two or more choices with the representative costs. Replacing the 70 Gallon Power Vented water heater and the cost, along with all the other suggestions made. Indirect's etc.

    When the numbers all come in, well over 90% of the time, when given the choice, the 70 gallon water heater would be replaced. 15 years is a long time for a water heater to not fail. Its providing all you need right now.

    When the water gets rusty out of the faucet, water on the floor is not long behind.

  • rsc92
    rsc92 Member Posts: 51
    Go Indirect?

    Kind of what i was initially thinking, but the prices to replace the Power Vent 75 gallon hot water heater are not materially different than going indirect.  Both plumbers are within $200 to $300 of one another and the indirect is only about $200 more to replace than the Power Vent.  With that said, should i go Indirect because it will give us more hot water or is it better to have a separate unit for hot water (in case the boiler fails, we still have hot water and vice versa).  Thanks
  • icesailor
    icesailor Member Posts: 7,265
    You're joking?

    You're joking?

    You may be correct about the close cost of the 70 gallon water heater and the 50 gallon indirect.

    But have you priced the indirect install completely? With the boiler modifications, piping, valves, wiring Etc? And compared the two?

    No matter how easy the adding of an indirect to a boiler that doesn't have one, it will always take longer to install the indirect over just rolling in with a new 70 gallon water Power Vented water heater and replacing it.

    I'm not against indirects. I just like to give people choices.

    I know that we don't discuss prices here, but I doubt that you could replace and completely install (walk away, done) the indirect for the numbers mentioned.

    If you price an indirect only, and someone (like me) gives the differences in cost between the two choices, and it is substantially cheaper to replace the like kind heater, and I get the job, You would be wondering why.

    There can be other "issues" but I won't bring them up in public here.

    Way back when, in the wild West days, when I started out, there was a plumber who was known as the biggest hackaroo in town. But he always had a lot of work. People that hired him always said " I know he does really bad work, but if you keep an eye on him, he does a good job". I never saw a good job. But people were willing to put up with shoddy work. And then, gripe about the shoddy job they got. But it was all about price.
  • rsc92
    rsc92 Member Posts: 51
    edited May 2014
    Got me Thinking

    What you say makes complete sense, but both plumbers are pushing the indirect and the price difference is not much at all between the Power Vent and Indirect.  As I said in my prior post, approx $200.  I wonder if they are jacking up the price of the Power Vent intentionally.  Time for another quote...............

    Curious though, taking price out of the equation, which is the "better" way to go?
  • Snowmelt
    Snowmelt Member Posts: 1,418
    edited May 2014
    Let them

    Explain on what there going to do.


    Where are they going to tie the copper in supply& return.

    What size copper should be minimum of 1 inch,

    Are they going to put a 3 way valve on top to prevent scolding ( that's a code thing)

    How are they going to wire it up,

    I will be guessing you have a taco zv-3 or 4 board there already.

    So yout looking at a indirect tank,

    Three way mixing valve

    1inch x 10 feet of copper

    10 1 inch elbows ( 5 supply 5 return)

    2 tees ( one on the supply & 1 on the return manifold)

    Zone valve or a circulating pump ( cost of either is less then $20.00)

    If the plumbers where good they would isolate the pump

    An extra ball valve and a tee with a drain to bleed the zone .

    If he was real good he would install unions and shut off valves to isolate the indirect water heater, or at least isolation valves, maybe not unions

    Except for last statement with the unions eveything else has to be done.

    I didn't even include the electric for the zone valve or the pump, also plumbing it all in will take time.

    With two people and if old water heater drains out correctly from start to finish, removing old water heater bringing out to truck and replumbing new water heater I will say 2 1/2 hours.

    With an indirect water heater it's more of a 5 - 6 hour job. 4 if the good and use press on there copper.

    The indirect is the way to go, some mfg. give life time warrantee,

    I'd still go with indirect and a circulator over a power vent water heater.

    Unless your going to move in next 5 years.

    TO MY FELLOW wet heads did I leave anything out.
  • MikeL_2
    MikeL_2 Member Posts: 501
    permit, fees, and inspection.......

    We always get a permit for water heater installations, and I like to be there for the inspection. Sometimes, there are existing conditions that need attention - inadequate combustion air, improper clearance to combustibles, incorrect wiring, faulty venting, etc. I prefer to have the building code official sign off on these existing conditions, and, often the home owner is more receptive to corrective measures when re- enforced by an additional authority. Repairing " discovered " mechanical defects benefits the home owner with the added value of increased safety, and I benefit from " add on " sales.
  • icesailor
    icesailor Member Posts: 7,265
    Leaving Out:

    ((( TO MY FELLOW wet heads did I leave anything out. )))

    I was told years ago, and it took me a while to really let it sink in, that we think we can do a lot more in a given time frame than we actually are capable of doing.

    Someone tells me that they can change a water heater in 1 1/2 hours, it's a morning. Or more. (4 hours?)

    Change a connected Indirect? More than a morning. (6 hours?) What do you do for the rest of the day? Go home?

    Change a gas water heater. Heater delivered between 9:00 AM and 9:30 AM. Drain the house by blowing the whole place out with air, after the owner gets water. Disconnect tank and move out of the way. Tina the delivery girl delivers tank and we take the old one outside. Less than a 1/2 hour. Connect new tank, gas/electricity and vent. Turn house back on, Put tank in truck to take for disposal. All morning.

    Install an indirect in place of old heater. Same as above. Except, drain entire heat system so I can cut piping in to add new zone. Re-pipe potable water piping to tank in new new location. Pipe new zone from boiler to indirect. Test for leaks with air. Fill heat system. Fill Potable water system.

    Almost forgot. Explain how to wire it to electrician.

    All day. A long all day. Tomorrow, I'll get rid of the old tank.

    Not allowing for the permits and inspections.

    I worked alone so I didn't have to wonder what I did with the spare body I was paying.
  • Snowmelt
    Snowmelt Member Posts: 1,418
    Ice sailor

    Didn't you just repeat what I said? I don't follow what your saying.

    Why would you drain the whole house. Don't you put a shut off on cold going into the water heater.

    Don't you have them deliver the unit day before.

    Ok now I know why it took you the whole day.

    Do you have viega press?

    I like to go a little faster get out of there.

    While I'm draining a unit my helper has the new water heater piped up with copper and gas line all completed.

    1 person brings old unit to stairs while other person hooks up venting and copper.

    Bringing unit up the stairs to truck 15 minutes.

    Repipe gas, start filling the water heater up , bleed the gas line , 5 minutes.

    Plug unit in. See flame at bottom of unit.

    Bill the costumer and leave.

    It takes 20 minutes to go get ride of old water heater.

    If I wanted I could just flip it in the metal container in less then 5 minutes and don't worry about flate tire.
  • icesailor
    icesailor Member Posts: 7,265
    edited May 2014

    #1: I worked alone.

    #2, the driver helped me remove the old heater if it was in a cellar. I only needed help dragging the old one up the stairs.

    #3, I drain the whole house by blowing it out with air so I don't get any drain back from water still in the system. I can drain a water heater with air while you're connecting your handy pump. And THAT is a fact.

    I'll kiss you somewhere if you can get your Viega press in many of the places I went. And my wholesaler didn't stock press fittings.

    You just described how you changed a water heater in 3 hours (or two hours which I doubt) You and two others. That's three men, two hours for a total of 6 man hours. Or, in three hours for a total of 9 man hours.

    Which I did by myself in 4 hours.

    Maybe you have a "floater" helper. laborer, but you still have to pay him for 8 hours. Unless you pay him cash for when he is around.

    There was a guy around (no longer, he went nuts). He did a lot of big foolish designer dream houses. He lost his shirt on every one. I asked him once if he ever went over his cost at the end of a job to find out his true cost to do the job. He told me that he hadn't done that in 15 years. That he was till using some of the same factors that he used  20 years ago. He didn't have time for that foolishness. He was always on the cash and carry plan with the wholesalers.

    Have you ever done a cost out to see what your true cost to change out this imaginary water heater? How do you allot "to and from" time for these imaginary employees? Not "Shop Time" I hope.

    Ii worked over 12 years for my old dead boss. I never had a helper/apprentice in my truck. If he sent me to change a dishwasher, he sent a helper out to help me get it out and in the yard. By the time help arrived, I had it out, in the yard, and was installing the new one. The only time I ever had a helper was after I had cancer surgery on my leg and had a cast on, I needed to work. So I asked him to give me all the crawl jobs because I could drag my cast around but couldn't walk. Which he did.

    Down in South Florida where I now live, a neighbor had a broken underground shut off. She had someone replace it. Two guys showed up. One to walk around and supervise (the helper), the other (with a big attitude, brought the pipes and new shut-off out of the ground about 2' from the building. So, you could walk between the shut-off and the building. With no support to the building. The customer wasn't happy. So, the attitude guy came back alone, and drove a piece of galvanized hanger strut into the ground and clamped it with a couple of galvanized TW clamp. Still, not connected to the building. A few days later, two more different guys came back and re-piped it with the ball valve about 20 degrees off from being parallel. One guy was supervised by the other, who spent most of the time on his Smart Phone talking and texting. They had more of all the right stuff in their trucks than I could have ever dreamed of. But then again, I once realized that I wasted a lot of gasoline driving a lot of heavy tools and equipment that I seldom used on a 80,000 mile ride in my van. You or I could have done the whole original job in two hours of billable time and mounted the shut off on the building.

    I feel like I'm slipping off into a depression. Thinking that I was doing it all wrong for all those years. But everyone always paid.
  • rsc92
    rsc92 Member Posts: 51
    Thanks for all of the feedback. Went indirect. Got the Burnhsm alliance. Took 2 guys 6 hours.