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down the Nut G union and pressure reducing valve rabbit hole . . .

aka, calling @Hotrod
so i noticed the latest caleffi 3/4" pictured with press x nut G unions that has a claimed SKU of 535651HA. So I go to the catalogue figuring that the 1/2" version with press ends will be right next to that but I can't find anything in the catalogue that even indicates what ends are supplied and I can't find the part number of even anything that starts 5356.

The competition is little more help. They don't have a cut sheets that lists the suffixes that apparently express the terminations.

For the life of me I can't see why it isn't more sensible for most distributors to stock a single item that has several connection choices. My distributor is out of Taco 3350-H3 which is their press connected version.

But, whenever I look to put a half dozen of these in stock i rekindle the same disconnect in my mind. Why is it virtually impossible to find specifications, washers, etc. for these unions. I thought this was the way circulators were going. TACO at least offers a set, but notice that under the specifications it only lists the press size and not the union size???!!,

For some reason of convenience and convention and to drive those of us who try to keep extra fiber washers around crazy they use a different size for backflow preventers, so how would I know which those fit. And I have no idea what size or several sizes the union threaded pumps are made in.

nuff nuttering about that. anyone got anything . . .

thanks,

brian

PS - @Hotrod what is a "pre-adjustable" valve? i've had preadjusted before but preadjustable?? is that indicative that it has a scale? and why is the range of all the Caleffi PRVs I seem to find seem to be 1-6 bar (forgetting that i hate converting all the time) and the preajustment abour 45 psi, e.g. 5350? Am I looking in the wrong place for typical residential hydronic PRV which I would expect a preset of 10ish psi with the expansion tank prefilled to 12? Not only doesn't 1 bar even go that low but i usually am looking for controls that i'm not running at the min or max limit of adjustment.

maybe the world is starting to go my way on bringing the expansion tank up to 18 and running the whole thing at a little higher pressure but that is still just barely at the bottom of the range of a 5350.

Comments

  • hot_rod
    hot_rod Member Posts: 17,408
    The 535 is a PVV for domestic water applications, not a boiler fill valve, so a 15- 90 psi range. below is a copy of the pricebook showing the options

    Some suppliers buy just the body then add the type of connection the plumber needs, mix and match any type, any size.

    The 573 is the boiler fill valve combo which has press options in 1/2".

    The 5350 is the 3/4" high flow boiler fill, available as just a body and you can add any 1" G thread fittings.the high flow is a 3/4" version.

    The challenge is the counter personal need to know they are selling just the body and to add fittings. Else the plumber gets to the job without the needed fittings.

    there is a fitting guide page that shows what fittings fit what bodies in the fitting section of the catalog.

    And the 2021 catalog is now online.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • mattmia2
    mattmia2 Member Posts: 6,537
    hot_rod said:


    The challenge is the counter personal need to know they are selling just the body and to add fittings. Else the plumber gets to the job without the needed fittings.

    That should probably be in large print all over the outside of the box along with the list of fittings on one side.
    Solid_Fuel_Man
  • hot_rod
    hot_rod Member Posts: 17,408
    mattmia2 said:

    hot_rod said:


    The challenge is the counter personal need to know they are selling just the body and to add fittings. Else the plumber gets to the job without the needed fittings.

    That should probably be in large print all over the outside of the box along with the list of fittings on one side.
    Yes, the box is labeled with a bright sticker, good idea to add fitting list options to the box, thanks
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • pecmsg
    pecmsg Member Posts: 3,315
    mattmia2 said:
    The challenge is the counter personal need to know they are selling just the body and to add fittings. Else the plumber gets to the job without the needed fittings.
    That should probably be in large print all over the outside of the box along with the list of fittings on one side.
    That’s called experience!hot_rod said:
    The challenge is the counter personal need to know they are selling just the body and to add fittings. Else the plumber gets to the job without the needed fittings.
    That should probably be in large print all over the outside of the box along with the list of fittings on one side.
    Yes, the box is labeled with a bright sticker, good idea to add fitting list options to the box, thanks

  • hot_rod
    hot_rod Member Posts: 17,408

    aka, calling @Hotrod
    so i noticed the latest caleffi 3/4" pictured with press x nut G unions that has a claimed SKU of 535651HA. So I go to the catalogue figuring that the 1/2" version with press ends will be right next to that but I can't find anything in the catalogue that even indicates what ends are supplied and I can't find the part number of even anything that starts 5356.

    The competition is little more help. They don't have a cut sheets that lists the suffixes that apparently express the terminations.

    For the life of me I can't see why it isn't more sensible for most distributors to stock a single item that has several connection choices. My distributor is out of Taco 3350-H3 which is their press connected version.

    But, whenever I look to put a half dozen of these in stock i rekindle the same disconnect in my mind. Why is it virtually impossible to find specifications, washers, etc. for these unions. I thought this was the way circulators were going. TACO at least offers a set, but notice that under the specifications it only lists the press size and not the union size???!!,

    For some reason of convenience and convention and to drive those of us who try to keep extra fiber washers around crazy they use a different size for backflow preventers, so how would I know which those fit. And I have no idea what size or several sizes the union threaded pumps are made in.

    nuff nuttering about that. anyone got anything . . .

    thanks,

    brian

    PS - @Hotrod what is a "pre-adjustable" valve? i've had preadjusted before but preadjustable?? is that indicative that it has a scale? and why is the range of all the Caleffi PRVs I seem to find seem to be 1-6 bar (forgetting that i hate converting all the time) and the preajustment abour 45 psi, e.g. 5350? Am I looking in the wrong place for typical residential hydronic PRV which I would expect a preset of 10ish psi with the expansion tank prefilled to 12? Not only doesn't 1 bar even go that low but i usually am looking for controls that i'm not running at the min or max limit of adjustment.

    maybe the world is starting to go my way on bringing the expansion tank up to 18 and running the whole thing at a little higher pressure but that is still just barely at the bottom of the range of a 5350.

    \Pre-adjustable means you can dial in the desired pressure before the valve is installed with the window on the 535 or the dial on top of the 573.
    We have a large tract home builder/plumber that buys pallets of PRVs. They want a 60 psi setting, so we readjust the valve from 45 to 60 psi for them.
    With the optional pressure gauge you can confirm the set pressure or troubleshoot a failed valve.



    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • archibald tuttle
    archibald tuttle Member Posts: 955
    @Hotrod thanks for part numbers sorting. i figured i wasn't finding the right ones.

    i'm just thinking, for the 1/2" residential which only has a union on one end anyway, why have multiple part numbers? put the press and sweat in. maybe there is a little more valuable metal but i would think the lower stocking costs could help keep mark ups in check and higher satisfaction ensues even if it needed to be a little more expensive. But it is way more valuable to me not to have to specify (and still might be worth having the 1/2" female on the inside of the union boss as i used to encounter, if you are coming up to the valve with pex. and you don't have to have a union style in the case usually because you can often leave a little excess in pex approach so you can cut the pex and crimp another adapter if you have to change it out-albeit we're not supposed to need to change them because of the great plastic cartridge (insert fingers cross emoji)).

    and while I can't find the union size specified with the listing for the PRVs I found the accessory fittings for PRVs on page 41 and it carefully spells out different union threads for different nominal size PRVs and for the backflow preventer on page 42 and you actually list the nominal union size!

    I still can't find where you go to see a chart for these unions that translates nominal size into the actual dimension and threading, something akin to the standard pipe thread chart. But thank you for pointing me to this useful info which allows me to back into those.
  • hot_rod
    hot_rod Member Posts: 17,408

    @Hotrod thanks for part numbers sorting. i figured i wasn't finding the right ones.

    i'm just thinking, for the 1/2" residential which only has a union on one end anyway, why have multiple part numbers? put the press and sweat in. maybe there is a little more valuable metal but i would think the lower stocking costs could help keep mark ups in check and higher satisfaction ensues even if it needed to be a little more expensive. But it is way more valuable to me not to have to specify (and still might be worth having the 1/2" female on the inside of the union boss as i used to encounter, if you are coming up to the valve with pex. and you don't have to have a union style in the case usually because you can often leave a little excess in pex approach so you can cut the pex and crimp another adapter if you have to change it out-albeit we're not supposed to need to change them because of the great plastic cartridge (insert fingers cross emoji)).

    and while I can't find the union size specified with the listing for the PRVs I found the accessory fittings for PRVs on page 41 and it carefully spells out different union threads for different nominal size PRVs and for the backflow preventer on page 42 and you actually list the nominal union size!

    I still can't find where you go to see a chart for these unions that translates nominal size into the actual dimension and threading, something akin to the standard pipe thread chart. But thank you for pointing me to this useful info which allows me to back into those.

    You are above my pay grade when it comes to parts included in the box :) I can pass along suggestions.

    Yes, it is usually a bean counter decision. We try to stay competitive with other brands and models, so we try to keep the COG in line.
    Adding even a $.25 part to several hundred thousand valves gets the $$mans attention.

    The US and Canada are the only 2 countries that buy NPT threads and our copper tube differs from metric size sold around the world. So we already build special tailpieces just for this market.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Solid_Fuel_Man
  • archibald tuttle
    archibald tuttle Member Posts: 955
    bean counting is a thing and i'm not running them down. but extra skus cost money (and possibly sales because of all the confusion although i tend to think most of the industry takes what they can get at the counter and, as the industry moves to press, distributors are probably moving to press packaging and nobody else is 'sweating' the small stuff like I do) so those are tradeoffs that fancy bean counters can model.

    that said, easy access to catalogued adapters with sizes rather than (or in addition to) applications is a reasonable alternative as long as these as disseminated in the supply chain. But one problem after further reviewing page 41. There are no 1/2" press tailpieces offered (nor 1/2" pex which is also listed in 3/4") . . . maybe that started after the 2021 catalogue?

    maybe I mistake the extent of units that go out in residential, light commercial vs. heavier industrial but I would think the 1/2" in residential would be by far and away the most popular skew and even more competitive if it had multiple tailpieces, especially since focus on install fittings for that series does not seem to be high in the catalog but that's me. that's meant to be helpful criticism and I here 2022 is coming so just trying to get in front of that .pdf. whose ear should i bend in vegas (since i bend yours here . . . )

    meanwhile the competition offers 1/2" press but literally their tech support can not tell me what size the union nut is nor is it specified for an application. (and they are working from home so they can't go out back and get one off the shelf. I'm thinking hazy should have just shipped 'em one of everything for a reference to fill the family room with :-)

    they do say i'm the only one who ever asked that question . . . i guess there is something wrong with me and not the specifications. of course they meant that in a friendly way :-)

    brian



  • hot_rod
    hot_rod Member Posts: 17,408
    edited January 12
    We have been trying to please all the suppliers, contractors, reps, engineers with tailpiece and nut selection.
    We made the decision to sell bodies only, as a request from distribution, a good idea I think.
    Here is where it got complicated, when they asked for packaged connection kits.

    Some valves only need 1 tail and nut, some need 2, and mixing valves need 3. So that became 3 different SKUs of all the various options, a 1 tail package, a 2 tail package, and a 3 tail package box. It got overwhelming for distribution to stock and know all those options, just knowing if they need 1, 2 or 3 piece kits with various body numbers.

    So we added section 8 to the catalog. Every fitting and fiber washer we offer/you need is listed as well as the application chart, even categories showing which products require 3/4, 1, 1-1/4 etc nuts

    By offering the nuts and tails ala cart now you can mix and match.

    For instance a 3 way mixer could have NPT on the hot to attach to a tank, copper sweat or press on the H&C, or press, or pex crimp, or pex expansion 1960, or any combination.

    You can also build a valve with 3 different connection sizes, a mixer could have 3/4 NPT on the hot to screw right onto a tank, 1/2 on the cold, 1" on the mix. The selection is near limitless.

    Most all tailpieces now have check valve options, another few dozen SKUs options:)

    I think we have 12 products now that all have 1" G thread and can take all the various tail pieces, zone valves, mixers, fill, balance, etc, etc

    SO... to make a loooong story long, did it get easier or more complicated?

    Is it less or more SHUs for wholesale?
    Will the counter staff know how to assure the correct kits or individual parts go out the door??? Should the customer know what he needs to add to the base body?

    Know also many other brands of valves have 1" G as the connection, so these Caleffi adapter parts can be sold along with other brands for ultimate connection configurations.

    Missing from our offering is the push gripper option, and CPVC adapter tails, still debating those options. I'm not a huge fan of either of those piping options
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • hot_rod
    hot_rod Member Posts: 17,408
    Plus 1/2- 2" gauge type tailpieces for most all the products
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • archibald tuttle
    archibald tuttle Member Posts: 955
    I can see with all the different valves and sizes just creating a readily parseable line of tailpieces. i'm not agin that although if there is one unit on the water pressure side and one on the heating pressure side that you sell orders of magnitude more of then you might still handle that differently. If guys prefer to have their preferred pressure dialed in they going to prefer to have it made up with their preferred tailpiece no doubt . . . but I'm not out to change that, and maybe i'm wrong because i literally have only installed the 573 or equivalent that this would be several orders of magnitude more units..

    so i didn't see that table on page 38 cause I thought I found the units for PRVs and Backflow preventers on 42 and didn't look backwards. In that page 38 table, only NA206456 is 1/2" press (it's x 1" nut union) and then on the next page 39 there's a 1/2" press fitting with 1" nut union, NA16264 (not sure the difference) and a 1/2" press by 1" nut union tailpiece, NA10403 which looks to be the same thing without a nut but lists for more (i guess most people want the nut). but no 1/2" press with 3/4" nut union that i can see that would fit the residential PRVs, your 573 or any competitors..

    as you point out there just isn't a standard but I guess you are more focused on 1" and up unions in this line you created. If you had a 573 that was aimed mass market residential that took a 1", I'd cue up because that is the same size as the backflow preventers. cuts my skus, spare washers etc . . . :-). but it seems that 3/4 is the standard for residential PRV but there is no press offering to fit it?
  • hot_rod
    hot_rod Member Posts: 17,408

    I can see with all the different valves and sizes just creating a readily parseable line of tailpieces. i'm not agin that although if there is one unit on the water pressure side and one on the heating pressure side that you sell orders of magnitude more of then you might still handle that differently. If guys prefer to have their preferred pressure dialed in they going to prefer to have it made up with their preferred tailpiece no doubt . . . but I'm not out to change that, and maybe i'm wrong because i literally have only installed the 573 or equivalent that this would be several orders of magnitude more units..

    so i didn't see that table on page 38 cause I thought I found the units for PRVs and Backflow preventers on 42 and didn't look backwards. In that page 38 table, only NA206456 is 1/2" press (it's x 1" nut union) and then on the next page 39 there's a 1/2" press fitting with 1" nut union, NA16264 (not sure the difference) and a 1/2" press by 1" nut union tailpiece, NA10403 which looks to be the same thing without a nut but lists for more (i guess most people want the nut). but no 1/2" press with 3/4" nut union that i can see that would fit the residential PRVs, your 573 or any competitors..

    as you point out there just isn't a standard but I guess you are more focused on 1" and up unions in this line you created. If you had a 573 that was aimed mass market residential that took a 1", I'd cue up because that is the same size as the backflow preventers. cuts my skus, spare washers etc . . . :-). but it seems that 3/4 is the standard for residential PRV but there is no press offering to fit it?

    We do our best to get the customer what they need.
    Anything with NA prefix is a part we make in the US. So for a customer wants a specific nut, tail, whatever.
    Italy needs to make 10,000 or more of a small part to retool the dies for the forge, retool the multi-spindle machines to build that part. So if we want to cater to a small order, or tryout a new fitting assembly for a customer we go to a local machine shop in Milwaukee that can crank out 1000 pieces out of bar stock, for example.

    If a customer wants a specific pressure setting and fitting assembly on a PRV for example, the Milwaukee warehouse staff has to un-box that product, which was assembled, tested, labeled and shipped on a container ship from Italy. We open the box, make the change, close, seal and label it. So it is not something we can do for small orders piece very easily.

    There was a time when we had both plumbing and heating nuts, tails, etc. The potable was a low lead brass, so that was an even more complicated numbering and making sure the wholesalers ordered the correct part #

    Yes it is possible to see a part in several sections. We always have the connection options with the product category. About 3 pricebooks ago we made that fitting selection chart and offered parts outside of the product category, offered bare bodies for customizing connections..

    Just to get on the same page here, PRV to me is a plumbing item, a pressure reducing valve. The 533 and 535 those take 1" nuts and fittings, or larger since they go to 2"
    15- 90 psi so not a good boiler fill valve.

    The 553 is a 1/2 boiler fill valve "AutoFill", it takes a 3/4 nut. FIP oin the outlet end only.
    Or the 573 which has a BFD attached and is available in 1/2 press, union in, press out of other combinations.

    IF you want to have the entire 1" nut selection for boiler fill, Autofills, look at the 5350. It fills at 9 gpm, roughly twice the flow of the 553 which is a 1/2 version. The 5350 has 3/4 and 1" fitting selection, any or all the 1" fittings could go on it if you order the basis body you could customize both ends of it, it is union on both ends.

    Off the top of my head only that 573, TRVs and manifold nuts are 3/4 G thread. The 1" is on many more products, ours and competitors.

    To keep it all straight in a NPT head :), the 3/4 G thread is the same diameter and thread pitch as a 3/4 pipe nipple, but it is a straight thread, no taper, needs a washer seal.

    A 1" G thread nut fits onto a 1" pipe nipple, no taper either so it needs a washer or o-ring seal.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • archibald tuttle
    archibald tuttle Member Posts: 955
    so the 3/4 inch G nut would fit 3/4" parallel pipe thread?

    only thing i didn't see in your answer is if there is a 1/2" press by 3/4" G Nut Union fitting. did i miss that in the list your you don't have a half inch press that would fit the 573?
  • hot_rod
    hot_rod Member Posts: 17,408

    so the 3/4 inch G nut would fit 3/4" parallel pipe thread?

    only thing i didn't see in your answer is if there is a 1/2" press by 3/4" G Nut Union fitting. did i miss that in the list your you don't have a half inch press that would fit the 573?

    I don't think the hole in a 3/4 nut is large enough to fit over the o-ring bump on a 1/2 press fitting? The hole in the nut would need to be small enough to press the flange against the assembly on the valve for the fiber washer to seal well enough, but still slip over the o-ring bump.
    I'll play around with it tomorrow.
    So a drop nut or 3 piece fitting with a blind snap ring if that is the case.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • hot_rod
    hot_rod Member Posts: 17,408
    yeah, not even close to getting a 3/4 G nut over the hump on a 1/2" press fitting
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • archibald tuttle
    archibald tuttle Member Posts: 955
    Are u sure you didn't try over 3/4" press. My 3/4 nut g nut (dept. Of redundancy department) goes over 1/2 press fitting high spot with 1/8" to spare all around
  • mattmia2
    mattmia2 Member Posts: 6,537
    Seems like you could just buy the NPT union and a male adapter or male reducing adapter to 1/2" or 3/4" press.
    hot_rod
  • archibald tuttle
    archibald tuttle Member Posts: 955
    edited January 14
    @mattmia2
    there is always a workaround and thats what i have been doing, but people are always seeking the most direct convenient solution to save time in the field, which is why you can now buy crimp isolation flanges instead of threading a crimp adapater into an NPT flange, and see at the extreme @hot_rod 's customer who wants PRVs set to a different setting than the factory.

    the biggest issue I have isn't even which tailpieces are included. I leave that to the broader market and distributors to sort out although I have my penchants. I would just like to have the connection sizes called out well.

    but this is the market of manufactures and distributors who, for the most part, don't offer size designations relative to the unions on their products (albeit Caleffi's application fittment listing is the best i've seen) and don't even have replacement washers, nevermind fittings, forward in the distribution network. i tried two distributors yesterday, one had no washers for these unions, the other had a couple laying around of one size but couldn't tell me which it was or what it fit. albeit again credit to Caleffi who have washers labeled for 3/4" and 1" applications at big online distributor. just ordered 10 of each which will go in the bin with my circulator gaskers.

    brian

  • archibald tuttle
    archibald tuttle Member Posts: 955
    edited January 16
    @hot_rod or we could be ships in the night as to what constitutes a 3/4" g union. i only have the competitors unit on my bench (I have several or yours installed and working but that doesn't leave me to easily check the actual nut size.

    but what I took to be a nominally 3/4" nut g union starts on a 1" pipe (doesn't thread on, different thread pitch as well as parallel vs. taper, not sure this would be so for all maufacturers. in any event, you had called them out as coordinate with pipe size so if you are trying a parallel nut that threads on a 3/4" pipe I agree with you but I don't believe that is a 3/4" nut G union as I understand the designation. that is why this style needs a standard dash size callout with diameter and thread per the nominal size (and if manufacturers are using different standards then call out at least major regular approaches, kind of like fine and coarse nut threads). I've never seen a G nut union smaller than the one I have in hand that starts on a 1" pipe. and this is the nut goes right over the shoulder on a 1/2" press fitting and is the transition from nut g to 1/2" press i'm looking for. the thread diamter is just under 1 and 1/4". I estimate the pitch at 14 (vs. pipe thread pitch of 11, but that is a guess)

    I don't recall changing to a smaller nut union when i changed several installs to caleffi but maybe your products work so long it was just long enough ago i don't recall it (who said covid brain is solely a symptom of one disease?)


    brian
  • hot_rod
    hot_rod Member Posts: 17,408
    There are all sorts of different nut sizes and pitch, notice our small BFD has an odd size fine thread nut. 

    Also the diameter of the hole in the nut can vary depending on what is is used for 

    As far as Caleffi goes:

    a 3/4 nut fits a 3/4 male Npt
    1” fits a 1” male NPT
    and on up to 2”

    The nut will screw down and bottom out on the male npt

    A fiber washer is needed to seal, although a pipe nipple doesn’t offer enough seating area

    Belt sand the end of a schedule 80 nipple and you can get a seal. Or the end of a copper male adapter has enough area.


    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • archibald tuttle
    archibald tuttle Member Posts: 955
    edited January 17
    got it, i forgot the input union is smaller on yours. i guess that is what comes of not having to replace them as often! and or it's proof i've had covid, or both. do you have a preference for the fiber vs. silicone washers?

    and thanks macguyver pipe capability in a pinch although I usually have the male on the autofill or backflow preventer or pump so it is getting the right nut and washer and connection scheme that matters. and it's back to the drawing board for a press connection for that small union. i guess i might have to break down and stock the IPS tailpieces and thread a press adapter in for the time being.