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Need Critique: New Heat and Indirect DHW

mikemac52
mikemac52 Member Posts: 45
A new heating and hot water system being installed into an old house. Navien 150 and Amtrol Hydromax indirect DHW. 4 Zones, 3 with cast iron radiators and 1 zone with baseboard heating.

I asked installer prior to work if he was installing a primary and secondary loop and he said yes but things seem a little different than I thought they would be.

Looking for advice on a couple of things in the photos to fall in 3 groups:

1) It's fine!
2) Not the best but not to worry, it will get you through the winter...
3) Change before he blows up the world!


Oh, yeah. We are waiting for this to finish before we move in. Hopefully before Thanksgiving :(

Does the piping qualify as a primary loop?
Is it necessary to have a circulator on the primary?
Should I ask for a filter on the return to the Navien?
Is the spacing between the 2 pairs of taco's okay?
Anything else that looks necessary?

Thanks for your time.


«1

Comments

  • hot_rod
    hot_rod Member Posts: 22,018
    Doesn't look to be a P/S. what size is all that piping?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    Installer? what does he usually install? I see some workmanship issues and serviceability issues. I don't like throwing people under the bus. I just see details that are red flags.

    This might be a 3. Where is the pressure relief valve?!

    With out a pump for the heater you don't have a primary/secondary manifold system. The way it is set up, even if it had a pump the piping arrangement would not be what the manufacture recommends.

    More pictures might help.
  • Ironman
    Ironman Member Posts: 7,366
    That's not p/s piping. Plumbers seem to be the hardest ones to get the concept because they think the piping can enter/exit the Tees in any fashion.


    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Ironman
    Ironman Member Posts: 7,366
    You didn't give the model number, so IDK if the boiler has an internal circulator. Take the door off and you can see.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • mikemac52
    mikemac52 Member Posts: 45
    @ Mr. Rod
    The supply and returns are 1 inch and 3/4 inch to the circulators and pex. (Then to 1 inch black pipe to the radiators.)
    If that ball valve wasn't there and the connections were closer, it looks like it could function as a P/S, with a weird turn on the supply side. Honestly though, I haven't a clue.

    @ Jolly Bobodger
    Pressure relief is at the top next to air release valve. Though I wanted to ask him if it shouldn't be directly in line and the pressure relief offset. (See pic below) I'll get more detailed pics.

    @ ironman
    The Model is NHB 150, I'm not there currently so can't check to see if there is internal pump. The info I have seen on line says it has a fan and a motor. Don't know if that is the same thing.


  • mikemac52
    mikemac52 Member Posts: 45
    No integral pump. They just list the blower and its motor separately.
  • Ironman
    Ironman Member Posts: 7,366
    The purpose of p/s piping is to accomplish hydraulic separation between the two sides. In other words, the two different flow rates can mix without interfering with each other.

    Example: the boiler could have 6 gpm through its loop while the house side could have 4-10gpm through its side without interfering with other.

    The way it's piped now, you've got hydronic interference, not separation.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    @mikemac52 (no space between @ and name)

    The pressure relief and air vent will work as is. But I agree I would have put the air vent straight up and the Pressure Relief off the side of the tee. It does not matter the orientation. Most of the time the relief valve is off the supply. Webstone make a nice set of valves for this application that provide isolation, service, union, and relief in one. Make sure the relief gets piped to within 6" of the floor.

    Navien calls for a Low water cutoff installed above the heat exchanger. I don't see one but it's not done yet right?

    It will provide heat as is as long as the valve by the heater is not open. This setup should be piped as shown above. Yes it needs a Primary circulator.
  • mikemac52
    mikemac52 Member Posts: 45
    So, I've been reading the manual...
    @Ironman & @Jolly Bodger
    The Navien has an integral low water cut off and says install an external if required by code. I'll have to look up NYC plumbing code. Don't think I'll trust his opinion at this point. And I'll look to see if he puts in the relief pipe.

    Another item I just read in the manual states the need for an expansion tank. Currently there are none piped in...

    So even without a circulator, with the first valve by the supply outlet closed the system should work, correct? Or does the primary circulator need to be installed no matter what.

    Is the current piping in any way going to interfere with the operation of the Navien or will this just cause inefficiencies in the system owing to hydronic interference. I guess I'm asking if he needs to change the piping. I'm already going to ask about an expansion tank, so I'll ask him to change other things if needed for proper function.

    I'm off to a meeting with the General Contractor. I'll take more photo's and let you know.

    Thank you
  • mikemac52
    mikemac52 Member Posts: 45
    NYC code:
    A second low water cutoff is not required on packaged wall mounted hot water boiler heating a single residence within a building.

    So, he's okay with that one...
  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    @mikemac52

    He has a spot for the expansion tank. It is the MIP pointing down off the fill line. It is in the right place.

    It will probably work since your heating system is mostly low head appliances. the Navien is a high Head heat exchanger. And they require a minimum flow to turn on. This is why they but a primary pump on it with a Bridal loop. it allows the heater to have all the flow it wants no matter what is happening at the zones.

    Depending on pump sizing and head loss you might not have enough flow on some zones if they are the only one calling.
  • mattmia2
    mattmia2 Member Posts: 9,572
    Why is the supply and return connected with a ball valve?
  • mikemac52
    mikemac52 Member Posts: 45
    @Jolly Bodger

    The MIP, is that the black cast iron thingy I was thinking was an air separator?
  • mattmia2
    mattmia2 Member Posts: 9,572
    MIP=male iron pipe thread (although that is female, the expansion tank is usually male). It is just below the ball valve in the lower right, it all comes off of the tapping in the bottom of the iron air scoop.
  • mikemac52
    mikemac52 Member Posts: 45
    @mattmia2

    Wish I knew. Heading over for a chat.
  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    @mattmia2 answered it. I did mean FIP not MIP.

    At least you should not have any air in the system with all those air vents. :)
  • mattmia2
    mattmia2 Member Posts: 9,572
    Er, the connection for the expansion tank is in the lower left on a tee just below the connection from the fill valve.
  • mikeg2015
    mikeg2015 Member Posts: 1,194
    edited November 2019
    Should have bought the prefab near boiler manifold with included pump flanges. It’s not that expensive and saves a ton of time, looks good as it’s already curved to fit.
  • hot_rod
    hot_rod Member Posts: 22,018
    The installation manual is pretty clear on how it should be piped. They offer kits if you don't want to build your own P/S
    https://www.navieninc.com/downloads/nhb-manuals-installation-and-operation-manual-en
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • mikeg2015
    mikeg2015 Member Posts: 1,194
    Figure the valves, flanges and unions cost maybe $220 in materials and it saves at least 1 hour labor assembling and all that yourself. I think it’s worth it to finish the job faster. that 1-2 hour might mean finishing 1 day sooner and avoiding 1+ hour mobilization.
  • mikemac52
    mikemac52 Member Posts: 45
    @Jolly Bodger @Ironman @mattmia2
    Right you were, expansion tank in place for the boiler.

    The pressure relief got piped properly.

    I didn't ask about the ball valve. After talking about hydraulic separation (he was impressed with my lingo :-) and the possibility of the smaller zones not having enough flow. We put off the discussion till tomorrow to be had with his plumber.

    @mikeg2015 @hot_rod
    His guy supposedly went through the Navien installation course so this confuses me more. He must know about the pre built manifolds and certainly how they should be piped.

    Another discussion will be about the expansion tank for the indirect and the magnetic filter for the Navien, both of which the G.C. didn't think it needs. I'm beginning to think this is about money...

    Thanks again, will let you know the outcome.
  • mattmia2
    mattmia2 Member Posts: 9,572
    What is the rest of the system like? was i originally forced circulation? how old is it? with that much iron a magnetic dirt separator is a good idea but if it is series/parallel loop zones substantially as it is now with small diameter pipes, it might be ok with just a strainer.
  • mikemac52
    mikemac52 Member Posts: 45
    @mattmia2

    1920 house, originally gravity, converted to forced circulation. Lots of 1" black pipe still in the walls of this balloon framed house. The radiators originally were fed off 2" headers run down the center of the basement. All runs to radiators on each floor were precisely equal. Now 3/4 Pex runs out of the room to where the black pipe starts up to the radiators.

    The fact that they are in series now irks me no end after the education I've been picking up here.

    The Navien instruction book threatens warranty discontinuation if sludge, flux, metal particles and the such get into and cause damage to the heat exchanger. So, out of fear, I was asking for the magnetic (and hopefully dirt) filter.

    Is reducing down to 3/4 enough the restrict particulate flow? Also, is buildup of sediment where it reduces going to be a concern in the future?

    @Jolly Bodger
    Yeah, It caught my eye the number of air vents, but wasn't sure. Well, perhaps I can make it into a pipe organ. B)
  • mattmia2
    mattmia2 Member Posts: 9,572
    If it is a converted gravity system, especially if you have rearranged the flow, a magnetic dirt separator is required. You will be stirring up all sorts of new stuff that has collected over the past 100 years.
  • mikemac52
    mikemac52 Member Posts: 45
    So I won the expansion tank request, and think I got the filter. Got more of an "okay if you think" answer on the last one.
    Lost the P/S discussion partly. Says he'll put in a circulator but the tees and connections are fine as is. The answer was, he is the expert and will be back to service it if there is issue. Not exactly an answer that inspires.
  • mikemac52
    mikemac52 Member Posts: 45
    @mattmia2
    It was converted to forced circulation late 70's but little was done to the piping. We've come in and shaken it all up, so that settles it, must have filter.
    Do you think it would be okay to fire up the system prior to the filter being installed just to test everything?
  • mikeg2015
    mikeg2015 Member Posts: 1,194
    Those heat exchangers are same as on a tankless. Very small passages. I would NOT fire it up without a dirt separator and/or magnetic filter.
  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    As @mikeg2015 says. and there is a small turbine the measures water flow. Though most of the junk would stick in the inlet screen. In about 30 seconds.
  • Ironman
    Ironman Member Posts: 7,366
    mikemac52 said:

    So I won the expansion tank request, and think I got the filter. Got more of an "okay if you think" answer on the last one.
    Lost the P/S discussion partly. Says he'll put in a circulator but the tees and connections are fine as is. The answer was, he is the expert and will be back to service it if there is issue. Not exactly an answer that inspires.

    That answer won't fly. He doesn't get to make up his own hydronic rules (which are dead wrong). The manufacture's are required to be followed and that piping arrangement defies them.

    You have a right as a consumer to INSIST that he follow the manual. The way it is now, the heat exchanger may fail because of insufficient flow.

    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    STEVEusaPA
  • Ironman
    Ironman Member Posts: 7,366
    Here are two p/s examples from the manual which hotrod posted above. One uses Navien's manifold and the other uses field fabricated closely spaced Tees. As you can see, the arrangement of the Tees is the same in both diagrams, but what you've got does not conform.

    Also note; the manual calls for 26-99 circulator on the boiler side. That's a very large circulator because the boiler's heat exchanger requires a high flow rate.




    Again I caution: this guy is gonna ruin your boiler if he refuses to follow the manual and continues to make up his own rules.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Jolly Bodger
  • hot_rod
    hot_rod Member Posts: 22,018
    send a pic to Navien tech support, ask if they will bless and warranty the installation. It is not a correct P/S, even with that valve left open.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    IronmanSolid_Fuel_Man
  • mikemac52
    mikemac52 Member Posts: 45
    Money. You can do anything you want, if you have time and money...
    @mikeg2015 @Jolly Bodger
    Took your advice, told him yesterday not to run the boiler till filter was in place. And of course...
    Rough morning. He didn't install a filter. They had just done a fresh water test with the boiler and I told the gentleman not to go any further until filter was installed. Contractor, who was not present, said not a necessary item and would not buy it. I'm afraid I might have been yelling a bit at the workers at that point, which isn't right as they are not making the decisions. Mostly...
    Plumber's reasoning for installing smaller pump on the primary rather than the one listed in the manual (and as @Ironman stated) was that the zones are using the same pump. All Taco 0015's.
    More like its a couple hundred dollars cheaper...
    @hot_rod
    Took your suggestion, Spoke to Navien tech and sent a pic with the circulator installed to them. The gentleman said he would take a look and get back to me. I threw in the Circulator question even though I know the answer will be... :o
    Ordered a filter and will have it Friday morning.
    If Navien doesn't get back to me today, Have a good Thanksgiving.
    Thanks for all of your perspectives,
    Michael



  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    @mikemac52 Danger, Danger Will Robinson!

    I didn't see that they piped the condensate drain in copper. You can't do that! Condensate is acidic. Notice the condensate neutralizer it is piped to? it will eat the copper and solder.

    Again, the bus thing, I hate to, but these guys are doing you dirty.

    And as a service tech I hate that they did not install any unions.
  • KC_Jones
    KC_Jones Member Posts: 5,722


    I didn't see that they piped the condensate drain in copper. You can't do that! Condensate is acidic. Notice the condensate neutralizer it is piped to? it will eat the copper and solder.

    I thought I was seeing things, probably because I couldn't ever imagine them doing this, but I guess with everything else it shouldn't be a surprise.

    I think the OP is going to have a battle on their hands here.

    Does your contract with them state anything about following manufacturers spec? If not you are surely in for a battle. If Navien doesn't like it and says it will void warranty that will be the ammunition you need.

    Another "Professional" job.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • mikeg2015
    mikeg2015 Member Posts: 1,194

    @mikemac52 Danger, Danger Will Robinson!

    I didn't see that they piped the condensate drain in copper. You can't do that! Condensate is acidic. Notice the condensate neutralizer it is piped to? it will eat the copper and solder.

    Again, the bus thing, I hate to, but these guys are doing you dirty.

    And as a service tech I hate that they did not install any unions.

    It makes no sense either, because PVC is not only better for condensate, it’s cheaper, quicker and easier to glue together and cut apart if it plugs up. Sigh.

    Why can’t these people open a manual. Meanwhile as a “licensed” plumber he’s probably making 30% more than me as a “newbie” service guy/installer.

    I think it will still work ok, but it’s not right.

    I like the red Bell & Gossett flanges on the green Taco pumps. Guess he had extra laying around. Sort of Xmas like.
  • mikeg2015
    mikeg2015 Member Posts: 1,194

    As @mikeg2015 says. and there is a small turbine the measures water flow. Though most of the junk would stick in the inlet screen. In about 30 seconds.

    I forgot they put a screen on there. Was thinking it was just the DHW. I try to remember to pull and clean them right after startup because bits of copper and tape end up there.
  • mikemac52
    mikemac52 Member Posts: 45
    I'm afraid... of what I might do next I see him.
    @Jolly Bodger
    Another thing I have to deal with him on. :( Thank you. (that's not being sarcastic.) Hopefully when Navien gets back and he needs to change piping, I'll chime in, and one more thing...
    @KC_Jones
    General contractor is a friend of the wife unfortunately. (probably not for much longer though) I gave her a form for him to sign about installing exactly as manufacturer states (I picked up that info here somewhere) but it fell through the cracks though we spoke verbally on it a couple of times. Plumber is his guy.
    @mikeg2015
    I've got red and green and black flanges!
    @Jolly Bodger @mikeg2015
    Could you give me a clue where to look for the small turbine/flow meter. Couldn't seem to find it when looking in the unit or on the exploded views in the manual. Cause I definitely will be pulling that after they've don't their tests.
  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    I looked through the manual, parts, and schematic. I can't find a flow meter either. Maybe this one does not measure flow? Just relies on the pump. But these are very low mass and are dependent on flow. Most of the time they are just past the inlet screen. Might ask Navien tech support.
  • mikemac52
    mikemac52 Member Posts: 45
    edited November 2019
    @Jolly Bodger
    Forget the bus, Navien threw me under an 18 wheeler.
    I was a little disappointed with their tepid response. They missed the hydronics issues completely. The most damming statement they came up with was, "I wouldn't say it would void the warranty, but the change in the circulator is beneficial to the operation of the unit."
    To be fair, on the phone, they did say, just follow the manual.
    So, new problems, condensed version.
    Saw installation problems, bent pipes (dropped the unit?) Called navien looking for tech to come. Sent me to their contractor web page. Called Navien Repair Service of New York. Michael said he is too expensive to travel just to look, so I should send him some specific photo's and he'll give it a once over and write down some things.
    Too many things wrong to draw up anything, he'd have to charge me. Gave me a list of issues to correct, the items I learned about here plus a handful of others. Gave to G.C.. The plumber walked...
    Michael Referred me to someone nearby. Will meet them tomorrow but he warned it will be expensive to fix. :(
    Thank you for all the info and pointing me in the right direction.
    Regards,
    Michael
    Return line bent 5 degrees to the left


    Gas line bent 10 degrees forward