Looking for Chicago Lake water experiences with Tankless

Discussion in 'Tankless Water Heater Forum' started by Dgilmour, Dec 24, 2012.

  1. Dgilmour

    Dgilmour New Member

    Messages:
    3
    Location:
    Chicago Area, IL
    Greetings,

    We are considering a tankless water heater here in the suburbs of Chicago. We are on "lake water" and so have really cold source water in the winter (I'm not sure what it is at the moment.. sorry..)

    I am hoping that those who live in the area getting lake water from Chicago can tell me if they are having good experiences or not and what their equipment is. We have a 3 bed/1.5 bath tri-level house. Family of 5 with kids starting the pre-teens. Laundry room is under the master bedroom.

    I am considering the Rheem condensing natural gas direct vent (H 95 http://www.rheem.com/documents/tankless-h84-direct-vent-indoor-tankless-95-indoor_outdoor-spec-sheet)

    How reliable has it been (repair history)?
    Repair costs? (I plan on performing my own "flushing" on a yearly basis.. so what are other maintenance costs?)
    How effective at getting to 120 degrees and holding steady?
    How loud is it when it fires up? Will it be an issue to have it under the master bedroom when I wake up early to shower and go to work and my wife will be trying to stay asleep?

    Thanks in advance for the honest truth.

    Sincerely,
    Doug
    Last edited: Dec 24, 2012
  2. lifespeed

    lifespeed Member

    Messages:
    321
    Location:
    California
    The Rheem looks like an interesting unit. Especially nice is the 11,000 BTU, 0.4 GPM startup flow. One difference with the tankless is they don't fire up until a minimum amount of water is drawn, and the minimum on this unit is nice and low. A bad child can pull a slug of cold water into the hot water pipe by trickling the hot water, causing the dreaded cold water sandwich. Personally, my experiences with the CWS have been minor and rare, more like a lukewarm sandwich ;) Other manufacturers start up at low flow, but Rheem may have bragging rights for the lowest. Not sure on this spec.

    A key specification, not listed in the Rheem datasheet, is pressure drop at GPM of flow across the heat exchanger. Of course it is important for any plumbing to not restrict flow, but this pressure drop can be significant and is a key figure of merit along with temperature rise. Noritz NRC1111, which is the only heater I have any experience with, has low pressure drop, high flow and high temp rise.

    You will need the largest heater available if your water is in the 45 degree range. No worries, they only use a lot of gas when you use the water. But you will need to feed it with a large gas pipe and gas meter. If this equipment is marginal in your house, you'll have to upgrade.

    I don't have personal experience with reliability on that brand. If a water softener is an option, it will help keep the heat exchanger free from scale.

    Edit: No experience on noise with that model either. Most tankless are reasonably quiet. Mine is in the attic above the master bath, so not that far away. I can barely hear it, even in the bathroom directly underneath. The water running in the shower is much louder. But use common sense and don't mount it directly over the bed. Also, noise can carry out the exhaust vent.

    Lifespeed
    Last edited: Dec 27, 2012
  3. Dgilmour

    Dgilmour New Member

    Messages:
    3
    Location:
    Chicago Area, IL
    Thanks for the reply. I'll look into the Noritz..

    I'm going to be remodeling the laundry room, so I had a plumber come in and re-do all of the gas piping.. I've also had Nicor upgrade the meter. So I have 1 1/4" pipe out of the meter to a "T" for a future generator.. Then it comes into the house at 1" and crosses the room tapping off 1/2 " for the dryer and 1/2" for the furnace.. drops to 3/4 for the hot water heater and taps off 1/2 from there for the kitchen stove.. and that's it...

    Anyone else with some experience in the Chicagoland area?
  4. Killer95Stang

    Killer95Stang New Member

    Messages:
    46
    Location:
    Southern CA
    I might not be much help, since I live in CA, but I did recently install one of the Rheem high efficiency Condensing tankless water heaters. After 8 months of service with the unit, I can't stop talking about how happy I am with my tankless heater. I am pretty lucky, since my tankless is located less than 15 ft from the farthest fixture, so I don't notice any difference from my old tank type heater. Also, I don't think I've ever experienced the "cold sandwich" that people talk about with tankless water heaters. Where I live, we rarely see temperatures below 40 degrees, so I can't give any info on how it works when its colder than freezing. I can say that my unit is located in a closet that is accessed with vents from the outside. At 40 degrees outside temp, the unit does not skip a beat, and has no trouble supplying two showers with unlimited hot water.

    Funny how the wife gave me "the look" when I talked about going tankless, or adding a water softener and RO filter system. After a few months of using these systems, she always talks to her friends about how much she loves them!!
  5. saphman

    saphman New Member

    Messages:
    19
    Location:
    Northwest Florida
    FWIW, I have that exact unit from Rheem though mine is the Paloma brand, Condensing tankless with the H95 spec's. Like "killer95STang" My unit has been flawless and supplies endless hot water to our three bath home. We are in North Florida but our water does get cold. Based on your gas system however I have concerns... These units are 199,000 BTU's and need a minimum of a 3/4 inch line. I have a 2 psi gas system running a dedicated 3/4" supply. It sounds like you are running 1/2 psi based on pipe diameters. If the gas supply is inadequate you WILL HAVE NOTHING BUT PROBLEMS running your Rheem H95. They are very sensitive to gas pressure. My unit is an indoor heater. I have placed it in a closet and with the door closed, it is quiet. These units vent with 3" Sched 40 PVC.
  6. Dgilmour

    Dgilmour New Member

    Messages:
    3
    Location:
    Chicago Area, IL
    Thank you for your reports and recommendations. Is there anyone in Michigan, Wisconsin, or Illinois on Lake Michigan water who can comment on winter time operations?

    -Doug
  7. lifespeed

    lifespeed Member

    Messages:
    321
    Location:
    California
    The heater doesn't know or care where you are, all that matters is the water temperature. Measure it.
  8. Dana

    Dana In the trades

    Messages:
    2,803
    Location:
    01609
    HuH?? The water temperature is the LEAST of it! The only thing water temp effects is the practical limit of the maximum flow that you can get at the programmed temperature. Lake temps in Chicago are right around freezing in mid-winter, (yes, the lakefront DOES freeze, eh?) but the water in the mains are several degrees above that due to the heating of the soil. Assume the seasonal low temp to be 35-40F unless you have shallow water mains serving your street. With 35F incoming water and 115F out (80F delta-T) a typical 199KBTU tankless delivers about 4.5 gpm, which is enough to support about two simultaneous normal flow ~105F showers with a bit of margin, but not three. (With two showers running if somebody else then turns on the washer or starts filling a tub you may hear some shouting.)


    More that water temp, water hardness is perhaps THE most important factor when looking at installing a tankless. Hard water sources scale up the heat exchanger of a tankless quickly, adding to maintenance costs, and cutting into longevity. Since all lake water is treated and probably buffered before entering the mains it's unlikely that you'll have a scale-up issue, but you can call your local water department and get a range of "grains of hardness" or parts per million (ppm) to expect out of the local water system. Anything under 2 grains/gallon (or ~35ppm ) means you can go for years, even decades without having to de-scale the thing. If it's over 5 grains/85ppm you'll have to descale on a regular basis to keep it flowing free and working efficiently. (How often depends on how much hot water you actually use.)
  9. lifespeed

    lifespeed Member

    Messages:
    321
    Location:
    California
    Measure the hardness too . . . :rolleyes:
    Personally, I address this with a softener.

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