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Wilo Pumps

Two times a 15-58? Maybe when I sold the old UPS 20-42 back in the late 80's for $130.00 or more! Without giving out our pricing to all the Wallies out there (AKA my competition) let's say contractors will be paying mid to high $200 (but under $300). I'll discuss this mis-understanding with our guys - sorry bout that chief (ya, I'm a Get Smart fan)!

Describing the Auto Mode is kind of difficult to explain even for me - it would be great to say "hey, it works, don't worry about it" but that ain't good enough.

Auto mode turns the build in "auto set-back" on. The ECO (and Stratos) has fuzzy logic that reads low system minimum temps vs time over the first 24 hours of operation (no actual setpoints - it learns the system on it's own). When it sees an extended low temp and slightly longer time period longer than what is saw in the first 24 hrs it understands there is a no heat demand and an opportunity to kick down to min speed.

When there is a call for heat the pump sees this as a temp change and immediately comes out of set-back and modulates it's speed based on what the system needs (as it did prior to going into set-back).

The auto mode can be turned off at any time (rotate the red "head setting" adjustment button CW) or reset (rotate CW and back CCW). The initial system warm up period might not be reality - the pump might need to be "re-taught".

Hope this is a better explanation...

Manufacturing in the US - I agree completely with your feelings. We currently build municipal water products in Thomasville Georgia, assemble/test HVAC in Chicago (alas I can not honestly call this "manufacturing"). Will we fully manufacture HVAC in the USA? Better question is how soon (can't let out too many secrets in one post right?).

Did you attend our wind-up? What a blast - to see Judy, Dan and the crew let loose was great. Man, Judy works so hard and gives so much back to the industry - nice to see her relax and enjoy...


  • Garritt
    Garritt Member Posts: 27
    Wilo Pumps

    Has anyone used Wilo Circulators? It is suppose to be a VSD motor modulating on electrical resistance. It claimes to work great with a zone valve system because it eliminates a pressure differental bypass valve. It also uses less wattage when zone valves close, where as a typical circulator would use more wattage to move less water. Some of the circulators are 3 speed - not VSD, but they look just like the astro series from Armstrong. They cost alot though. A VSD Wilo costs around $500.
  • Steve Thompson (ST)
    Steve Thompson (ST) Member Posts: 7
    Wilo Pumps

    Update/claification on WILO. PexRunner, you raise a lot of good points…

    1) We have standard constant speed single and three speed circs – and they are about the same price as similar competitor products.

    2) Our “VSD” circs are far more than VSD circs. I have to apologize because a full explanation is difficult in an E Mail format. If you would like detailed information send me you mailing address and I will be happy to send you a training CD.

    3) Cost at $500 USD? No, we have small residential ECM pumps that are less than $500 and commercial high flow ECM pumps that are over $2,000. Depends on the size.

    4) Update on the WILO ECO (residential ECM circ) – UL approval was achieved last Friday (true story), product is on the boat as we speak – due into Chicago in 3 to 4 weeks.

    I can be reached at [email protected] for more information.

    Thank you for the interest…
  • Rob Blair
    Rob Blair Member Posts: 227
    Wilo Eco

    Hey Steve,

    Can you drop 2 off on the way between the boat and Chicago?

  • Ed_26
    Ed_26 Member Posts: 284
    Wilo ECO

    Info from my supplier is ECO available only in 230v. Is the residential model 120v?
  • Mitch_4
    Mitch_4 Member Posts: 955

    Are the training CD's free? I would be interested in one
  • Mark Hunt_6
    Mark Hunt_6 Member Posts: 147
    ECO voltage

    The ECO will be available in both 230v and 115v.

    Hope this helps!

    Mark H
  • Mark Hunt_6
    Mark Hunt_6 Member Posts: 147
    Training CD's

    Hi Mitch.

    E-mail me your address and I will see that you get a CD.

    They are free.

    Thanks for the interest!

    Mark H
  • Mitch_4
    Mitch_4 Member Posts: 955
    Will do

    Thanks Mark
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928

    Have not used, but did attend their training/info seminar.

    Here are the highlights--well at least according to me...

    1) 220V operation ONLY. Don't let this scare you though because U.S. 2-wire 220V, 60H can be used without any problem. You'll just need a little more communication with Sparky as you'll need a 3-wire (2 hot + 1 ground) service for the circulator. While I'm not positive of this, I believe that you can "borrow" the 220V from an existing circuit (like for a clothes dryer). Additional fuse(s) for the circulator(s) themselves [might] be required as these circs draw FAR, FAR, FAR less power than any typical 220V appliance you'll find in an American structure. The built-in overload/overcurrent protection in the circs [might] negate such a requirement--I'm truly not sure.

    2) Very high quality construction with all reasonable expection of a very long, trouble-free service life.

    3) The currently available Wilo Stratos models offer a number of operation modes:

    a: Delta-p: The circulator will attempt to modulate to maintain a constant delta-p regardless of flow rate.

    b: Delta-t: The circulator will attempt to modulate to maintain a constant delta-t regardless of flow rate.

    c: Delta-p mod: This one gets a bit tricky. Modulation is based on delta-p, but not at a fixed level. From my observations of the Wilo "brain box" this mode is based on systems with variable flow and delta-p via modulating, non-electric zone valves (e.g. TRVs, FHVs or remote-sensing non-electric "zone" valves). Most important thing to remember here is that these 2-way valves are not "on" or "off"--in most situations they operate somewhere between "on" and "off". As these valves modulate between "on" and "off", they inherently change the delta-p in the circuit--the more they're "off" the greater the delta-p; the more they're "on" the less the delta-p. In essence, delta-p mod mode will sense the general degree of "openness" of the collective non-electric zone valves. The more they're open, the more the circulator will work; the more they're closed, the less it will work--if all of them are essentially closed, the circulator will be doing essentially no work. This is EXACTLY why this mode of operation will eliminate the need for a differential pressure bypass valve in a system using non-electric zone valves.

    d: User-adjustable operation via deep coding. Essentially [I believe] delta-p mod operation with the ability to set minimum/maximum thresholds.

    4) Cannot be used in the primary (boiler) circuit nor as the only circulator with condensing/modulating boilers in systems without a LLH or primary/secondary. Why? Because there is no direct communication between the boiler and circulator brains. Nuisance lockouts (due to boiler overheat if circulation is too low and burner output too high) can be expected if conditions (user-desired or weather) change too rapidly. Wilo is supposedly working with this problem by working with mod-con manufacturers to allow both the boiler and circulator to talk to one another, but frankly I won't hold my breath...

    5) Extraordinarily energy efficient.

    6) Very expensive. Other than suitable commercial applications or "fantasy" residential, I cannot imagine using the Stratos to for "zoning via pumps".


    Now the "cheap" model--the Wilo Eco which may or may not be available in the U.S. at present.

    While far less expensive, the Eco has ONLY one mode of operation: delta-t mod

    My "imagineering" tells me that delta-t mod is best suited to systems with non-electric, proportional zone valves.


    1) Delta-t mod mode is designed around the operation of non-electric, proportional zone valves that are the STANDARD in Europe.

    2) In a system zoned with on-off valves (motorized or solenoid) system delta-p is a CONSTANT based on the zone with the greatest head loss. If the system designer has done his job in such a system (FAR more difficult than with non-electric valves by the way) either all zones have the same head loss (radiant floors with equal tube lengths) or he has intentionally normalized the head loss by varying tube size, using "flow setters" etc. In other words, the engineer EXPECTS a STEADY delta-p. In other words he has VERY intentionally designed his system around a constant delta-p regardless of how many on-off zone valves are open. My observation of delta-p mod mode tells me that if a single zone in a system using on-off valves calls, that delta-p will drop and you will not achieve your design flow.


    Again, I have not used the Wilo ciculators--this is all imagineering.

    The Stratos is amazing, but expensive and unfortunately cannot at present directly communicate with the boiler.

    The Eco, while relatively inexpensive, is not particularly well-suited to systems zoned via wall thermostats, zone valves, etc.

  • Mark Hunt_6
    Mark Hunt_6 Member Posts: 147
    Hi MIke

    Couple points.

    The Stratos is only available in 230v and is marketed as a "commercial" circ. The small Stratos has a shut off head of 20' and could be used on a residential application.

    The modes of operation on the Stratos are Delta Pressure Variant, Delta Pressure Constant and Delta Pressure Temperature.

    The ECO will only be Delta Pressure Variant and will be available in both 230v and 115v.

    Delta Pv mode requires that the installer set the maximum head that the circ should be required to produce. As system requirements change, the circ will speed up or slow down but will not exceed the rpm required to achieve the maximum head set point. (Delta Pv is the factory default setting)

    Delta Pc mode requires that the installer set a desired head setting and the circ will spin at the required rpm to maintain the head set point. I have a contractor in NY that used this mode for a ground source geo system. 8 wells of equal depth and distance from the HX. The required head does not change but the flow rate will as they use more or fewer of the wells.

    Delta PT mode requires 4 inputs from the installer. Max Head, max temp, min head and min temp. The Stratos will ramp up or down according to temperature rise or drop.

    As far as cost is concerned, a fixed speed circulator with a VFD would cost more than the Stratos. Add to that the PDV that is still required with the fixed speed circulator and the Stratos is much less expensive.

    The Delta Pv mode is perfect for zoned systems with zone valves since it will respond to the system requirement rather than constantly running at full rpm like a fixed speed circ does. The ECO will only run at max rpm when the system requires it to do so.

    When I do presentations with the Brain Box, I start off by showing what the watt consumption of a fixed speed circ is. The fixed speed circ draws 106 watts.

    I then fire up the Stratos circ that is on the Brain Box and I match the differential pressure and flow that was produced by the Star circ. The Stratos draws 46 watts.

    I really enjoyed getting to hang out with you in Denver!

    Mark H
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928

    Thanks Mark. Don't know why I said the Eco was delta-t mod--knew it was delta-p mod. Arggh! Will correct when I'm at the right computer.

  • Steve, the wilo guys in the booth in hartford ct. said the eco. would run about twice what a 15-58 goes for. This sounded to good to be true, I assume thats if we are paying in euros!

    Should we be worried about the future of german imports? I say get the manufacturing over here, so we can feel more secure about these relationships.

    I was a bit disappointed with the explanation I received regarding the pumps logic when in auto mode (left side of dial). Can you direct me to any literature that explains this in greater detail. "Trust me it works" just doesn't cut it for me.
  • scott337
    scott337 Member Posts: 38
    Don't forget about GRUNDFOS!

    They have a similar offering, less set up than Wilo from what I am told and the reliability ofthe Grundfos name. Proven! Durable! Reliable!

  • Steve, thanks for your explanation. In defense of your staff the "trust me it works" line came after an attempted explanation, I must have had a look on my face that said "huh". The important point that I missed is that the pump (in auto mode)is "looking" at temperature in (addition to head), makes more sense to me now.

    As I understand it (now) the auto mode adds temperature monitoring and will put the pump in a reduced mode when it "perceives" that there is a reduced call for heat.

    I'm assuming that this (auto) feature would most effectively apply to true (euro) constant circulation systems, not typical (U.S) thermostat and zone valve system w/odr.

    This looks like a perfect match for a Vitodens piped primary/secondary to trv equipped rads. Although against the recommendations of some I prefer direct connection when possible. I Would love to see systems with primary secondary "communication"

  • Weezbo
    Weezbo Member Posts: 6,232
    Say, Mark, i misplaced my cd

    that i had in the class in Anchorage a while back..

    would you happen to have another you might drop in the mail ?

    i bought 6 of the bronze body mostly for the motor :)

    soon as i finish the boiler install Bang i am on it like a cheap suit.*~/:)

    banging in the Wilo bronze bodies..

    i tried one in a gravity potable as a prime "Pump" the head pressure wasnt quite as high as i thought it would be..
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928
    Reasonable Residentially Speaking...

    [In delta-p variant mode] it's a perfect match for any boiler piped primary/secondary (or with LLH) to TRV or other "non-electric zone valve" equipped emitters of any sort.
  • Mark Hunt_4
    Mark Hunt_4 Member Posts: 68

    No problem.

    Just e-mail me your mailing address and I will get one to you.


    Mark H
This discussion has been closed.