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Deciding on a new switching relay (Taco vs Caleffi)

What's your preference? Argo and Honeywell boards don't have the dip switches that seem very useful to have (especially the pump cycle/exercise that will regularly run the pumps for a short window).

Taco and Caleffi really seem to be on par with each other feature-wise. Even if the older Taco SR506-EXP didn't have any dip switches but the newer SR506-EXP-4 does.

Comments

  • hot_rod
    hot_rod Member Posts: 23,224
    We put some nice features in the Caleffi relay boxes.
    Dip switches, 3 wire connections for the t-stats, thermal fuse on the transformer, no wire nuts needed with all the terminal screws, 6 ground wires under screw. 3 year warranty

    https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Caleffi - ZSR106 - Wiring Guide.pdf
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Alan (California Radiant) Forbes
  • lost11
    lost11 Member Posts: 37
    hot_rod said:

    We put some nice features in the Caleffi relay boxes.
    Dip switches, 3 wire connections for the t-stats, thermal fuse on the transformer, no wire nuts needed with all the terminal screws, 6 ground wires under screw. 3 year warranty

    https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Caleffi - ZSR106 - Wiring Guide.pdf

    Any kind of isolating relay board to connect smart thermostats to?

  • Wellness
    Wellness Member Posts: 149
    edited April 2023
    After a decade with the ZVC406-4, I recently switched to the Caleffi (ZVR106) and I've been very pleased with it: Much brighter LEDs to tell which zone valves are calling for heat. Neater single molex termination of transformer wires and more secure attachment of the circuit board to the mounting base rather than the flimsy standoffs that Taco uses. I also like that Caleffi uses a beefy plastic base rather than Taco's metal base, less opportunity for electrical shorts. As HotRod said, virtually no need for wire nuts when using the Caleffi board.
  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,500
    Never tried a Caleffi and I'm sure they're excellent, but then again once I changed from Argo to Taco about 20 some odd years ago, I've had no reason to switch.  Its you're choice. I do use some Caleffi Products..  very good  I know and Love Taco products, The White Family and their employees.  I'm Taco-Biased...Guilty!  Ha ha Mad Dog
    JohnNYAlan (California Radiant) Forbes
  • mattmia2
    mattmia2 Member Posts: 10,819
    edited April 2023
    My only complaint about caleffi products is that some of them could be better presented on supplyhouse.com, like the zone valves or the mixing valves where you have to assemble a group of parts to get a functioning valve, like the body, the unions, and the actuator. If Caleffi has an online tool to spec the parts then there should be a link there, if not then the catalog page should be in the documentation. No one wants to have to contact a rep to pick out the parts.

    There should be a step by step chart, pick one of these, pick x of these, pick one of these, optionally pick any of these.
    GroundUpMikeAmann
  • hot_rod
    hot_rod Member Posts: 23,224
    mattmia2 said:

    My only complaint about caleffi products is that some of them could be better presented on supplyhouse.com, like the zone valves or the mixing valves where you have to assemble a group of parts to get a functioning valve, like the body, the unions, and the actuator. If Caleffi has an online tool to spec the parts then there should be a link there, if not then the catalog page should be in the documentation. No one wants to have to contact a rep to pick out the parts.

    There should be a step by step chart, pick one of these, pick x of these, pick one of these, optionally pick any of these.

    Should be able to buy any Caleffi zone valve complete, or ala cart on supplyhouse
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • hot_rod
    hot_rod Member Posts: 23,224
    If you have thermostats with split sub-base, an AC type sub base, feed all the T stats from a stand alone transformer, then the Rh & C are the dry contact to switch the relay box. That should separate the transformers. Often times heat/ cool thermostats get power from the AC equipment, check the sub base wiring, there should be contacts for the heat.

    The Caleffi ZSR will be going out with removable 40 Va transformers now, same as the ZVR boxes. So you should have plenty of transformer power on board. Needs to be a relay with a 2023 date code, that is when they started going out with 40 VA instead of 15- 20Va, common on switching relays.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    MikeAmann
  • mattmia2
    mattmia2 Member Posts: 10,819
    edited April 2023
    hot_rod said:

    mattmia2 said:



    Should be able to buy any Caleffi zone valve complete, or ala cart on supplyhouse

    I see they have complete stuff now. it seems like it was mostly individual parts last time i looked. it is still far more versatile that way, you can make far more combinations than they could ever stock complete, I just wish it were a little less confusing to pick out.
  • hot_rod
    hot_rod Member Posts: 23,224
    mattmia2 said:

    hot_rod said:

    mattmia2 said:



    Should be able to buy any Caleffi zone valve complete, or ala cart on supplyhouse

    I see they have complete stuff now. it seems like it was mostly individual parts last time i looked. it is still far more versatile that way, you can make far more combinations than they could ever stock complete, I just wish it were a little less confusing to pick out.
    It is a comprehensive line of zone valves. About 50 versions of the body, then 11 various actuator choices.

    Supplyhouse does a great job of attaching the tech data and the product guide on most all the Caleffi components.

    I wish there was a way to make it easier. Perhaps not many people understand why there are 5 different Cv options. We do have customers for pretty much every body option offered.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    mattmia2
  • @hot_rod said:
    Perhaps not many people understand why there are 5 different Cv options.
    You briefly went over that in another thread, but it didn't stick in my small brain. Can you edify me or point me in the right direction? Thanks, hr.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    STEVEusaPA
  • hot_rod
    hot_rod Member Posts: 23,224

    @hot_rod said:

    Perhaps not many people understand why there are 5 different Cv options.
    You briefly went over that in another thread, but it didn't stick in my small brain. Can you edify me or point me in the right direction? Thanks, hr.

    The lower the Cv, the smaller the opening, orifice in the valve.

    The smaller that opening the higher the pressure the valve can close off against. The delta P that the circulator develops. See the pressure number next to the Cv number on the chart.

    Low Cv valves are used on hydronic, packaged air handlers to be able to shut off against high head circs, for example.
    Or a LL low lead valve used on DHW piping.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Alan (California Radiant) Forbeskcopp
  • lost11
    lost11 Member Posts: 37
    edited April 2023
    hot_rod said:

    If you have thermostats with split sub-base, an AC type sub base, feed all the T stats from a stand alone transformer, then the Rh & C are the dry contact to switch the relay box. That should separate the transformers. Often times heat/ cool thermostats get power from the AC equipment, check the sub base wiring, there should be contacts for the heat.

    The Caleffi ZSR will be going out with removable 40 Va transformers now, same as the ZVR boxes. So you should have plenty of transformer power on board. Needs to be a relay with a 2023 date code, that is when they started going out with 40 VA instead of 15- 20Va, common on switching relays.

    I just have a boiler and a indirect water tank. The board I'll be replacing is the Argo Armp 6P. 4 separate 2-wire heating thermostats (battery powered). i would like to start upgrading them to smart thermostats (between ecobee or honeywell). And indirect water heater.

    In regards to the 40VA or 12-20VA, is there any way to tell? Like a different sku? Over at Supplyhouse the description says 12VA or 20VA , same on the Brochure. The wiring guide also states 20VA for the ZSR (but 80 VA for the ZVR) on page 10 of the PDF. Again, 20VA on the product overview. I'm ready to order!
  • hot_rod
    hot_rod Member Posts: 23,224
    Its a rolling change on the relays with the 40va transformer, so it depends on their stock or when they last received a shipment. You would need someone to look at the box for the 2023 date code. Or look inside.The transformer is packaged separately it snaps into the box connects with a molex plug.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • lost11
    lost11 Member Posts: 37
    hot_rod said:

    Its a rolling change on the relays with the 40va transformer, so it depends on their stock or when they last received a shipment. You would need someone to look at the box for the 2023 date code. Or look inside.The transformer is packaged separately it snaps into the box connects with a molex plug.

    thanks. i'll call supplyhouse and ask. but do you have any official document in caleffi's website about this updated model? i hope you know the only reason why i'm going with caleffi is because you actually respond. it's nice to see a company being active in the community.
    Mad Dog_2
  • mattmia2
    mattmia2 Member Posts: 10,819
    There is someone from taco on here that will respond too, just not as frequently.
    Mad Dog_2
  • hot_rod
    hot_rod Member Posts: 23,224
    lost11 said:

    hot_rod said:

    Its a rolling change on the relays with the 40va transformer, so it depends on their stock or when they last received a shipment. You would need someone to look at the box for the 2023 date code. Or look inside.The transformer is packaged separately it snaps into the box connects with a molex plug.

    thanks. i'll call supplyhouse and ask. but do you have any official document in caleffi's website about this updated model? i hope you know the only reason why i'm going with caleffi is because you actually respond. it's nice to see a company being active in the community.
    I’ll check with the tech writers and literature team tomorrow to see when the update will go online.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,500
    edited April 2023
    Mr. Joe Mattielo from Taco checks in regularly.  Great guy...Back in the "Hungry Daze" (Deep Purple 1984) all the major companies had a representative here.  It is a very wise practice.   Dan wrote about this years ago and I personally adopted it at once:  (paraphrasing)  "When you're done with an installation or project, make THAT follow up phone call that you may not want to..send that comment card to Guage the client's satisfaction with your work.   As uncomfortable as this may be, you'll head off ANY problems at the pass BEFORE they tell the whole neighborhood about their perceived issue.  If there IS any issue, you have a chance to clean it up quickly and leave them happy 😊. "  This struck me as a bold and simple but perfectly 👌 common-sensical practice.  There are always going to be clients who are very difficult 🙃 to please, but if you're going to do battle in this arena, you should confront any issues head on before they can harm your rep in any way.  It is rare the guy or company that does this but it is a very wise practice of looking yourself in the mirror.  Another gem of sage advice by Mr. Holohan!  Mad Dog 
  • dko
    dko Member Posts: 668
    Is there a reason to further mention the Taco guys when there is already a Caleffi guy doing what you say the Taco guys would also do? The OP already stated he is going with Caleffi because hot_rod is doing what you say Taco could do. I don't see how further mentioning the guys that are not even replying to the topic adds any additional benefit unless there was some bad mouthing but there was not.

    Just seemed a tad distasteful.

  • GGross
    GGross Member Posts: 1,233
    For what it is worth, I just checked my stock of ZSR relays, we received them 9 days ago and they still have 20VA transformers. I don't think the change has gone through yet.
  • Dave H_2
    Dave H_2 Member Posts: 583
    I've read the posts when they went up but I wasn't there from the beginning trying to stay on vacation with the family but alas, here I am because we can never just "take off" any longer. We love this stuff so much that this is also what we like to do in our spare time!
    The two boards are practically identical from either manufacturer. There are two models from Taco, the standard ZVC and the ZVC-EXP boards.
    When the "new" models came out 12 years ago, the difference between the two were the standard ZVC didn't have the dip switches and the extra features as well as a less expensive price. The -EXP models has those dip switches so that they can be customized to match your system. We also moved the lights to the front and made them brighter.

    Dave H.

    Dave Holdorf

    Technical Training Manager - East

    Taco Comfort Solutions

    GGross
  • lost11
    lost11 Member Posts: 37
    GGross said:

    For what it is worth, I just checked my stock of ZSR relays, we received them 9 days ago and they still have 20VA transformers. I don't think the change has gone through yet.

    Oh. Yea.. I can't find anything (even on their website) about a higher transformer
  • lost11
    lost11 Member Posts: 37
    edited April 2023
    Dave H_2 said:

    I've read the posts when they went up but I wasn't there from the beginning trying to stay on vacation with the family but alas, here I am because we can never just "take off" any longer. We love this stuff so much that this is also what we like to do in our spare time!
    The two boards are practically identical from either manufacturer. There are two models from Taco, the standard ZVC and the ZVC-EXP boards.
    When the "new" models came out 12 years ago, the difference between the two were the standard ZVC didn't have the dip switches and the extra features as well as a less expensive price. The -EXP models has those dip switches so that they can be customized to match your system. We also moved the lights to the front and made them brighter.

    Dave H.

    how dare you take a vacation and not be available to us 24/7!

    at least Taco and Caleffi innovated. Argo just gave up on their Arm board in favor of the much more expensive universal board.

    the fact that the boards are basically the same was the reason i made the post thinking "What am i missing that someone more experienced dealt with"
    Dave H_2
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,599
    dko said:

    Is there a reason to further mention the Taco guys when there is already a Caleffi guy doing what you say the Taco guys would also do? The OP already stated he is going with Caleffi because hot_rod is doing what you say Taco could do. I don't see how further mentioning the guys that are not even replying to the topic adds any additional benefit unless there was some bad mouthing but there was not.

    Just seemed a tad distasteful.

    I like Taco because they have supported this site since it began. They, and the other advertisers, make this place possible.
    Retired and loving it.
  • dko
    dko Member Posts: 668
    I distribute Taco, no issue with Taco. and I was definitely overreacting.

    Imaginary situation in my head:
    Customer is deciding between products A and B. Representative for product A starts assisting and customer makes a decision to go with said product. Then two bystanders comment, "representative for product B also does that!"

    In my mind, what was the point of that after the customer made a decision? Sway them away? Had nothing to do with the brands themselves.

    I just projected my negative thoughts onto others.

  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,599
    @dko, thanks for explaining. I appreciate that.
    Retired and loving it.
  • lost11
    lost11 Member Posts: 37
    edited April 2023

    dko said:

    Is there a reason to further mention the Taco guys when there is already a Caleffi guy doing what you say the Taco guys would also do? The OP already stated he is going with Caleffi because hot_rod is doing what you say Taco could do. I don't see how further mentioning the guys that are not even replying to the topic adds any additional benefit unless there was some bad mouthing but there was not.

    Just seemed a tad distasteful.

    I like Taco because they have supported this site since it began. They, and the other advertisers, make this place possible.
    I'm not as active and new compared to many of the other people, but Caleffi doesn't?

    Thank you to all the manufacturers and brands that support the website and community <3 I support this site by adding it to my white list, lol
  • lost11
    lost11 Member Posts: 37
    dko said:

    I distribute Taco, no issue with Taco. and I was definitely overreacting.

    Imaginary situation in my head:
    Customer is deciding between products A and B. Representative for product A starts assisting and customer makes a decision to go with said product. Then two bystanders comment, "representative for product B also does that!"

    In my mind, what was the point of that after the customer made a decision? Sway them away? Had nothing to do with the brands themselves.

    I just projected my negative thoughts onto others.

    We all have royalties to the brands that's been working well for us :smile:
  • fenkel
    fenkel Member Posts: 162
    id throw the tekmar line in as well.. 3 year warranty and last zone post purge post purge operation of the last operating zone to maximize energy savings. The tekmar also provides a RoomResponseTM signal to modulating-condensing boilers to optimize comfort
  • lost11
    lost11 Member Posts: 37
    fenkel said:

    id throw the tekmar line in as well.. 3 year warranty and last zone post purge post purge operation of the last operating zone to maximize energy savings. The tekmar also provides a RoomResponseTM signal to modulating-condensing boilers to optimize comfort

    i see https://www.supplyhouse.com/Tekmar-306P-306P-Switching-Relay-6-Zones-w-Priority
    and they have an additional transformer too https://www.supplyhouse.com/Tekmar-M3069-Transformer-120V-Primary-24V-Secondary-40-VA

    what's the A/tn4 " Away signal connecting tekmar thermostats" ?
  • fenkel
    fenkel Member Posts: 162
    A/tn4= RoomREsponseTM signal.. it uses 0-10V or 0-24ma signal to control the temp of the boiler..