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Ball type zone valve or thermo-electric?

RetrosPexRetrosPex Posts: 56Member
Is there any inherent advantage to either traditional ball type zone valves such as Taco, Caleffi, or Honeywell, or the thermo-electric types now being offered by several companies? I'm primarily interested in 3/4" threaded, or Pex A connections. The new Caleffi units like the 676 series look very interesting. I don't know if this style valve is offered by other companies.

Do the Caleffi thermo-actuator heads have the same reliability as heads sold for use with a manifold? They look considerably larger, and hopefully more rugged.



  • RetrosPexRetrosPex Posts: 56Member
    It looks like I posted this in the wrong area. I'll have to avoid reading interesting posts on steam heat......
  • IronmanIronman Posts: 5,084Member
    We prefer the Taco sentry zone valves.
    Bob Boan

    You can choose to do what you want, but you cannot choose the consequences.
  • hot_rodhot_rod Posts: 11,609Member
    Thermo electric are ideal if you want a perfectly quiet, slow acting operation. Up until recently they have been real energy hogs. New low current draw versions 250 mA, draw considerably less juice. You can run 6 or so on a 24 Va transformer.

    Any motorized, or spring return valve will make some noise.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • RetrosPexRetrosPex Posts: 56Member
    Hot rod: I'm not concerned with noise, or speed. These will be in the basement. Which would you recommend for reliability? I know this is repeating info, but I'm looking at Caleffi, and Cross manifolds for about 12-14 total zones. Combo of underfloor, panel radiators and in slab. Have never used an actuator, or a cast/machined manifold with any kind of flow control. I guess it is fair to say that it is possible I'll solder up copper manifolds, since I have all the material here. That is why I'm looking at these options.

    Frankly, I don't like the looks of TRV's on a radiator. It seems to me that if you are buying a manifold system, it makes sense to make use of the components designed for that system. But, I don't want to be replacing actuators every year or two.

    It sounds like both the Taco and Caleffi zone valves are pretty good. When it comes to thermal actuators I have no clue.

  • hot_rodhot_rod Posts: 11,609Member
    Are you looking for actuators for a manifold, or a stand alone zone valve?

    I'd bet a lot more circulators get returned than our Z-one zone valves and we are closing in on 1 million sold! Especially with ECM and potential magnetite these days.

    New "brand name" zone valves should have 100,000 cycles or more, that is what we tested to.

    Paddle type ZVs like the Z-one are less sensitive to bad fluid quality compared to circulators and ball style valves.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • IronmanIronman Posts: 5,084Member
    By the time you make up your own manifolds and the buy zones valves and a ZVC panel, you'll have spent more money and be worse off than had you bought a good manifold like the Cross.
    Bob Boan

    You can choose to do what you want, but you cannot choose the consequences.
  • RetrosPexRetrosPex Posts: 56Member
    Rod: The question you ask is exactly what I'm trying to decide. The first step was to decide against using circulators to zone with, even though I have them on the shelf. Then decided to use Grundfos ECM and a zone device instead. Now, trying to decide if I should put thermal actuators on a manifold, (or) solder up copper manifolds and use zone valves, (or) buy a manifold system and do a hybrid.
  • RetrosPexRetrosPex Posts: 56Member
    Ironman: in your experience, are the actuators that go on a manifold such as Caleffi more or less reliable than a good stand alone ZV?

    As much as I like the look of the Cross unit, I am not convinced that the plastic ball valve is going to hold up long term. It also scares me that it is proprietary. So, I'm pretty much set on Caleffi. Now, do I do thermal actuators, use TRV's, etc? I'm looking for reliability more than anything else. Last week it was -32F here, actual temperature. Not a good time for a failure.
  • hot_rodhot_rod Posts: 11,609Member
    Thermal actuators on the manifolds would be the most sensitive ZV to bad water quality. If the stems seize up then the actuator, or mount will fail.
    The old style Honeywell/ Sparco/ Uponor PowerTracks actuators were famous for blowing their cases apart. Again not the valve fault per say, but hard water scale seizing the pins.

    By far the Caleffi Z-one is the most durable zone valve, handles almost any fluid condition, high flow rates, easily serviced if the motor were to fail.

    Ball valve style should exercise daily in my mind, two complete revolutions to keep the ball from sticking over periods of non use. Our ball style electronic mixing valves all exercise like that daily.

    TRVs are another method altogether, no ZVs required just pipe manifold right to each emitter. This gives you easy room by room or radiator by radiator control.

    Millions and millions of TRVs are used across the globe, dozens of manufacturers in Europe, simple, reliable, non-electric, proportional control, hard to ignore all those benefits. ECM and TRV would be the most efficient and user friendly IMO.

    Some would say ECM ∆P circulators were developed specifically for TRV systems.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • RetrosPexRetrosPex Posts: 56Member
    HotRod: That is exactly what I was looking for....a direct to the point answer. Simple and elegant. I'm going to order Caleffi manifolds and get on with this project. Two further questions for you: 1. What is the "niche" or reason for the new plastic manifolds you sell? Any reason to buy those over the standard series? Is it related to water quality issues?
    2. We have hard water here due to limestone and well water. What would you recommend for treatment of water in a system? I have a water softener system but it is not currently hooked up.

    Thank you HotRod.

  • hot_rodhot_rod Posts: 11,609Member
    Let me make sure I am following your plan.

    Are you considering a zone valve on each manifold, the supply for example?

    Or a zone valve on branches of the manifold?

    As you see the Z-one valve would not fit on the close spacing of the manifold ports, really an actuator would be better.

    If you want Z-one valve manifolds I would get a copper stub manifold from Sioux Chief, Watts, or Alberta T-drill.

    My opinion is boiler water needs to be under 10 grains per gallon hardness, or the TDS below what to manufacturers suggest. If not warranty is void day one.

    You must be in Canada, yes the plastic manifolds deal with water issues better, and typically are less $$ to manufacture.

    Collect some rain water before it touches the ground :)
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • RetrosPexRetrosPex Posts: 56Member
    HotRod: specifics: feed/return from my Boiler Buddy will be 1" HePex, distance to manifold for new addition is 28'.
    1. 2 in-slab loops of 270' each, 1/2" HePex. On thermostat, ZV or actuator.
    2. Master bath underfloor plates 240' 1/2" HePex. Thermostat, Zv or actuator.
    3. Master bath panel radiator/TRV valve.
    4. Master bedroom: 2 loops 300' 1'2 HePex, underfloor plates., Thermostat, zv or actuator.
    5. Master bedroom (2) wall mounted panel radiators, with TRV.
    6. Master closet, 1/2 HePex, extruded plates that are on the loop feed/return for the prior 5 zones. No separate control, just use zone manifold to balance the heat.

    Addition is highly insulated, tight construction. Plan is to use the in-slab (basement), and underfloor (first floor) plates to "take off the chill", and use the panel radiators to deal with temperature swings. I'm thinking 10 zone manifold. There will likely be (4) manifolds for the entire house.

    Manifold 2: 2 bedrooms, each with a panel radiator and TRV
    Both bedrooms some underfloor plates.
    2 bathrooms, both to have panel radiators with TRV.
    Both baths to have underfloor plates under tile.
    Manifold fed by 1" HePex, 25' from tank.
    This area over crawlspace.
    Manifold 3: Kitchen: underfloor plates, large panel radiator.
    Storage room, in-slab heat.
    Dining room, underfloor plates, panel radiator/TRV
    Manifold fed by 1" HePex, 20' from tank.
    Manifold 4: large living room 800 sf. A lot of underfloor plates. (5 loops?) No good place for panel radiators. Manifold fed by 1" HePex 30' from tank. This area over crawlspace.

    May be additional zones for garage, not yet determined. Likely in-slab heat only.

    Likely to be a glycol/heat exchanger loop for ice melt for gutters.

    Grundfos Alpha2 circulator feeding each manifold.
  • hot_rodhot_rod Posts: 11,609Member
    So of the 4 manifolds how many need zone control on each manifold?
    How many different temperatures?
    Are you able to get slab, plates and radiators on one temperature? Is manifold 1 everything in the first paragraph? I see manifold 2,3, and 4?

    Sounds like a blend of TRV and ZVs on all the manifolds?

    If all the manifolds have ∆P ECM then they could just remain powered all the time and a TRV or ZV call would wake up the cir and supply the gpm you need.

    So the buffer will need to be maintained hot by the boiler call from the tank so you always have a constant heat available.

    TRV zones do not have a way to call on a boiler unless you find an ECM circ with an end switch, or use an induction relay on that circulator.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • RetrosPexRetrosPex Posts: 56Member
    HotRod; Everything in the first paragraph would be on one manifold. My house is shaped like a wide, open "Y". I could possibly try to get all the underfloor on one manifold, but if I centrally located a manifold, the farthest underfloor zones would be 70' in one direction, 40' in another, etc. So, just the supply and return lines would use up a lot of tubing. In that case, I'd run larger diameter tubing, like 3/4" over to the load, and then transition down to 1/2". There would be a couple thousand feet of underfloor total...that is a lot of tubing. Total first floor area is 2400 sf.

    The panel radiators would be evenly spread out around the house. I plan to home run 3/4 HePex over to them, transition to 1/2 at the radiator. I want to keep pumping losses to a minimum.

    I don't think it is possible to do all of this with one temperature, unless I bought or made up just a small manifold for the couple in-slab loads. That might be an idea. I have a new 3/4" Caleffi mixing valve sitting on the shelf, those loads would not total a lot. The largest is a basement family room, highly insulated with ICF foundation. BTU load is about 3000 for that zone.

    This is why I've been asking questions about the best actuators or ZV to use, to evaluate just sweating up a copper manifold, or buying a unit like the Caleffi. My first thought was to not use any TRV, and just home run the radiators and use a ZV, or actuator.

    The storage tank is set up with a dedicated Grundfos circulator, as is the domestic water unit. So the Boiler Buddy will always be hot. Part of my logic was to use roughly 2/3 the amount of floor plates I'd need to keep a zone heated to 68-69f, so there was always a call for heat to activate the ECM pump. Maybe set it to keep a room/rooms at about 50-55F. Then use the radiators to do the rest. Of course, if I put the radiators on a thermostat, that would also give us the call for heat. I have a pile of new Ecobee wifi thermostats I got for next to nothing at Habitat for Humanity,so their cost doesn't matter. They can control multiple stages, so that might work for the underfloor plates, and radiator scenario. (?)

    I'll have to add up these loads, and make a drawing to see just how it might lay out to try to put one type of load on each manifold. My supply and return manifolds off the buffer tank are set up with (6) 1" Pex A fittings and ball valves.

    My intent is to buy 1.25" manifolds, no matter what. All the same. Thanks again.
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