Noritz tankless water heater - installed correctly???

Discussion in 'Tankless Water Heater Forum' started by thediver, Mar 12, 2011.

  1. thediver

    thediver New Member

    Messages:
    9
    Location:
    California
    We have a Nortiz tankless water heater model N-069M. It takes a little while to get the hot water going. After being in the shower for about 10 minutes, it suddenly goes ice cold. And I mean REALLY cold. It takes a good full 3-5 minutes before the hot water gradually comes back. No other appliances running and no one else using water in the house.

    I noticed some corrosion at the couplings near the bottom of the tank. I was also wondering about the flue? Does this tankless water heater appear to be installed properly. (Side note - will be posting this under a different topic, but also getting electric shocks from all water faucets in the house. Not when touching the faucet itself, but when touching the water. I know this is an electrical issue, but was wondering if this might be a grounding problem related to the tankless water heater. Electric shocks also felt when turning on lights, TV, computer, etc. Not all the time, but a lot of the time.)

    Here's the photos. Would love opinions. Thanks!

    Amy

    http://img138.imageshack.us/i/img4235wr.jpg/
    http://img141.imageshack.us/i/img4236g.jpg/
    http://img59.imageshack.us/i/img4239qi.jpg/
    Last edited: Mar 12, 2011
  2. Dana

    Dana In the trades

    Messages:
    2,924
    Location:
    01609
    Y-ing a power vented tankless into a common flue with the furnace/boiler presents serious safety issues, particularly (but not exclusively) if the other unit is atmospheric-drafted (which yours appears to be.) Test with a smoke-pencil or dangling thread/spiderweb to see if exhaust from the tankless is being actively back-drafted into the furnace room out the dilution air intake of the furnace/boiler when only the tankless is running. (Try the converse as well.) You may be able to tell with your nose or hand. If yes DON'T USE IT, and vent them seperately ASAP.

    Also according to Section 8 on page 45 of the manual, the N-069M vent pipe needs to be category-III (stainless steel) for it's entire length, which your installation clearly isn't. This installation faux pas will result in condensation in the flue eroding masonry in unlined or tile-lined chimneys, and the lifespan of that B-vent and galvanized flue piping won't be very long. While chimney damage is potentially expensive to repair it isn't likely to present the immediate health hazard of the combined flue issue. (Though it can be, longer term.) The date of manufacture appears to be 2004 on the front label. If it's been running 4-5-6 years into a masonry or tile lined chimney that chimney needs to be inspected for damage. (Dilution air from illegitimate vent connection to the other appliance may or may not have saved the chimney from damage.)

    The gas lines appear to be necked down to 1/2" flex line, which also doesn't quite cut it for a 190KBTU+ appliance. (There may be more issues than that with the total gas line length to the gas meter/regulator too, particularly but not exclusively when that furnace or boiler is running/starting during a hot water draw.) See the table on p. 47. Get out a tape measure paper and pencil, see if the distribution line is up to the total burner capacity.

    The reasons for the flame-out and re-start symptoms can be several, but probably are not related to the improper flue venting installation, but the gas line issues might be (or not.)

    IMHO this unit needs to be re-commissioned by a competent installer before worrying about the operational issues. However...

    Beyond the tankless, it's possible that the temperature/pressure valve (the one with the yellow tag on it below the water heater) is opening up, cutting hot water pressure to the shower as it dumps most of the hot water outflow, eventually re-closing slowly as the output temp of the tankless drops.
  3. davep1234

    davep1234 New Member

    Messages:
    2
    Location:
    78754
    We had the same problem [hot water going off and on, mostly off and staying off] and solved that problem by doing a twice a year 45 minute white vinegar flush to the unit.

    When done be sure to flush the unit with clear water to remove debris and the vinegar.

    There are many web sites that explain how to do this.

    Before this can be done; since in your particular configuration, there are no faucets to connect to, inline hose faucets need to be soldered onto the incoming and outgoing copper pipes about 8” from the unit.

    At the same time, remove the iron couplings – it is best not to mix metals here [mixing metals in water pipes causes corrosion] the pipes and fittings should be all copper for the water pipes [not sure about the gas pipe]. It would be preferable to solder all copper through to the unit when the faucets are added.

    After the vinegar flush, run plenty of hot water through every faucet in the house to remove vinegar and debris from the pipes. Remove and clean the screens in all the faucet aerators.
  4. ditto


    this should never have been instlalled into the chimmney... I was told that the heat
    levels are so high comming off a tankless heater that even going into a masonary chimmney
    it still is too hot...


    the gas line is too small... it does not take a brain surgeon to see this....

    I notice that the romex connector for the electrical is actually pulled out of the tankless heater..maybe you have a ground or bare wires touching inside the unit??
    wether that is the reason you are being shocked or not is something that you ought to look into
    soon.... you should look into this very soon indeed....

    For gods sake , whatever you do, dont call a competent electrician.. and do not call
    a competent plumber to make repairs to the unit.....

    find another hack off of Craigs list to check this out.:D


    oops this thread is a few years old already..... hope they did not
    electrocute themselves.....:D
    Last edited: Feb 10, 2013
  5. Scott D. Plumber

    Scott D. Plumber In the Trades

    Messages:
    67
    If I had seen this DANGEROUS and ameture installation I would have taken it out of service imediantely. Did you even bother to read the instructions? You are going to kill someone one day. This is positive pressure vented product installed with single wall galve vent and you didn't even try to seal it! You are pumping CO into the house of this poor homeowner who was unfortunate enough to hire you. THe gas connector is WAY too small, you probably don't have the gas line sized right either.

    This is why some people don't like tankless. Because people who don't know what they are doing install them wrong and then have trouble with them. I hope you get this fixed before you kill your costomers.

    If any you Homeowners out thre are seeing this THIS IS WHY YOU SHOULD ONLY DEAL WITH PEOPLE ON THE DEALER NETWORKS OF THE MANUFACTURERS! I run into this type of stuff regularly and eventually someone is going to be killed botched installs like this.
  6. Scott D. Plumber

    Scott D. Plumber In the Trades

    Messages:
    67
    I see this is a pretty old post. I hope the HO has got this corrected and I see Dana hit all the points I did long before I showed up. If AMY is the HO, she should call the local plumbing and gas inspector and report this idiot. I'm saving disaster pics into a file I have on bad installs. YIKES!
  7. thediver

    thediver New Member

    Messages:
    9
    Location:
    California
    So we had this reinstalled by a Nortiz tankless water heater installer back in July 2011. Here are the photos. What do you all think?

    For "Master Plumber Mark" - It never was installed into a chimmney.

    Still having some issues with the water suddenly going cold. Nortiz technical support tried to tell me this issue would be resolved if I hired a plumber to come out and adjust the manifold pressure with a digital monometer. Hmmmm. Haven't done that yet, because I have bigger concerns... I noticed after the reinstall, but it seems to have gotten worse. When the hot water is in use, I smell a strange gas-like chemical smell coming from the outside vent. Instead of screwing around with plumbers and installers, I called our gas company and they were happy to come out for free to check for gas leaks.

    No gas leaks found. Everything good with their line coming into the tankless water heater, but coming out the vent were high levels of CO2 - aldehydes. I don't know what the numbers mean but he said it was 189 PPM and 311 air free. He told me under 100 is safe and over 400 is extremely dangerous. At 311 he said it needed to be addressed. It is normal for tankless water heaters to vent our aldehydes at high levels? I called th Noritz install and he tried to tell me that's what the vent was for. I guess I don't believe anyone anymore at this point. I don't think the levels should be so high I can smell them.

    The Nortiz heater was running at 120,000 BTUs when the shower was running alone. This tankless water heater is rated up to 194,000 BTU. No error codes.

    Would you guys mind taking a look at the photos and tell me if the install looks okay and what your thoughts are on the aldehydes?

    IMG_4819.jpg IMG_4820.jpg IMG_4821.jpg
  8. lifespeed

    lifespeed Member

    Messages:
    321
    Location:
    California
    Is that 1/2" gas line? How many feet of pipe and number of elbows to the meter?
  9. thediver

    thediver New Member

    Messages:
    9
    Location:
    California
    The gas line supply is now sufficient. Confirmed with Noritz. 1" for about 45 feet and 3/4" for about 10 feet down to the very short flex. It used to be 1/2" for the last 10 feet before the modifications.
  10. joemcl

    joemcl In the Trades

    Messages:
    30
    Location:
    Pennsylvania
    I have been told by a factory rep for another mfgr, never to use flexible gas connectors on their tankless. With high gas demand ridges in flex lines can cause your gas pressure to waffle. Also you need to consider more than the gas supply to your noritz when figuring the gas. Calculate all btus in the house. Furnace, range, dryer,gas logs, you may not have adequate sizing for total load. Gas meter can even be too small. We run in to gas supply issues quite often on tankless. Improper gas pressure can cause the problems you are having. There is more to it than the size of pipe supplying the unit.
  11. thediver

    thediver New Member

    Messages:
    9
    Location:
    California
    We had the gas line upgraded to the proper size by one of their authorized installers and confirmed with two other tech support reps that the gas in adequate. Flow into the unit has been tested and is fine.
Similar Threads: Noritz tankless
Forum Title Date
Tankless Water Heater Forum Noritz N-063 tankless water heater, lose HW pressure and then no HW Jan 24, 2014
Tankless Water Heater Forum further improving/automating recirc pump control with Noritz tankless Dec 18, 2012
Tankless Water Heater Forum Tankless sizing, Noritz NRC98-DV versus NRC111-DV Mar 28, 2012
Tankless Water Heater Forum How loud are tankless hot water heaters, Noritz NRC98? Mar 14, 2012
Tankless Water Heater Forum Noritz NR98-OD Tankless water heater Nov 16, 2011

Share This Page