Is the 007 Overkill in HWB Installs Using Zone Circulators?

Rob R. wrote:Taco has a new 007 on the market. ECM motor.

Sweet! I hope they soon follow up with an ECM version of the 005. Or that AquaMotion does. My only concern is that the new generation of circulators seem to have plastic replacing cast iron. Will they last as long?

ECM motors are DC. There must be a transformer converting the AC current to DC, and that in itself is a power loser (despite the overall huge energy savings of ECM). If they ever come out with a straight DC version that eliminates the transformer, I could potentially run it directly off of my solar panel systems batteries. A nice thought for the future.

Sorry , no power waster is part of the ECM design concept. It is accomplished by way of very frugal solid state componets that result in far better effiencies than the long standing standard PSC motors that the ECM supersedes, and these latest ...they truly are Smart Pumps bring more than just the ECM feature to the hydronics world.

All these innovative circ. pump technologies are driven in large part by the European market due to their much higher electric rate structures. We can benefit here in NA but we are just a seconday maket for these newer pump innovative technologies.

McGiever wrote:Sorry , no power waster is part of the ECM design concept. It is accomplished by way of very frugal solid state components that result in far better efficiencies than the long standing standard PSC motors that the ECM supersedes, and these latest ...they truly are Smart Pumps bring more than just the ECM feature to the hydronics world.

Good to know. Now if only they could lose the plastic.

Don't quote me on this (yet), but I believe the Taco ECM's are made in Italy.

It has a seriously odd pump curve vs the traditional 007.

$111.22 through Amazon.com

A bit pricier ECM alternative, but for the extra money you get Delta-P variable speed, a built in check valve, Made in the USA (I believe, again, don't quote me), and cast iron. 4 variable speed pump curves. 3 fixed speed pump curves.

https://www.amazon.com/AquaMotion-AM55-FVL-ECM-Circulator-Pu ... AquaMotion

http://aquamotionhvac.com/wp-content/uploads/2008/08/Einstein-Brochure.pdf

By matching my systems calculated friction head by zone to this circulators lowest variable speed program curve (program PD1) I believe (on paper at least) that this circulator will deliver in my single circulator system something close to the following:

1 zone open : 2.25 GPM, 22,500 BTUH, ~535 BTUH per foot of baseboard
2 zones open: 4.25 GPM, 42,500 BTUH, ~505 BTUH per foot of baseboard
3 zones open: 6.00 GPM, 60,000 BTUH, ~476 BTUH per foot of baseboard
4 zones open: 7.33 GPM, 73,300 BTUH, ~436 BTUH per foot of baseboard

If this doesn't cut it, there is always PD2, then PD3, and lastly PD4, each with higher output than the one beneath it.

My first intuition (wherein admittedly intuition generally makes for seriously bad science) is that a gang of Delta-P variable speed circulators would likely be far less appropriate for use in a multiple circulator zoned system, since there would be no variability on each given zone (which after all is what it is) and each zones circulator would thereby end up functioning just like a fixed speed circulator. Can anyone who has tried this verify that they see no speed/GPM output changes day in and day out by zone?

This is where a gang of appropriately sized to each zone single speed ECM circulators would really shine. Or if the zones differ widely in length and in feet of baseboard, a 3-Speed ECM (which doesn't appear to exist yet, but will) would be just the ticket if you desire to use the exact same circulator for each zone. The more costly multiple variable speed circulators option would work perfectly also (sans as described above), but would be an overkill in price if you had to buy 4 or 5 of them.

Larry, much of the benefit of a delta P circulator is that it "right sizes" itself for the zone. There may not be a good ROI by doing it, but you could use one for each zone.

A delta P pump will re-adjust on the fly, so a single delta P pump can work it's magic w/ zone valves.

I agree that zone valves make the best use of that style pump, but my point was that some models can be adjusted to the exact fixed output you want.

Stay tuned...I just ordered a Grundfos Alpha to try on my system. I have a noisey 007 paired with 4 small zones that should be a good candidate.

I just ran the figures for my systems friction head vs. the Grundfos Alpha in "Auto Adapt" mode, and then in its lowest "Constant Pressure Mode" setting.

If the Alpha selects the very lowest end of its "Auto Adapt" pump curve throughout its range when set on Auto Adapt, I should get approximately this:

1 zone open : 2.7 GPM, 27,000 BTUH, ~642 BTUH per foot of baseboard
2 zones open: 4.6 GPM, 46,000 BTUH, ~547 BTUH per foot of baseboard
3 zones open: 6.8 GPM, 68,000 BTUH, ~540 BTUH per foot of baseboard
4 zones open: 8.5 GPM, 85,000 BTUH, ~506 BTUH per foot of baseboard

And if I set the Grundfos to its lowest "Constant Pressure" setting I should get approximately this:

1 zone open : 3.2 GPM, 32,000 BTUH, ~762 BTUH per foot of baseboard
2 zones open: 5.5 GPM, 55,000 BTUH, ~654 BTUH per foot of baseboard
3 zones open: 7.5 GPM, 75,000 BTUH, ~595 BTUH per foot of baseboard
4 zones open: 9.4 GPM, 94,000 BTUH, ~560 BTUH per foot of baseboard

I really like the "Auto Adapt" output, but how do I force the Alpha circulator to follow the very bottom end of its 'Auto Adapt' pump curve. It seems to be pre-programmed, and its programming is (I assume) fixed, but to achieve what end game? This same question applies to the AquaMotion variable speed circulator.

Rob R. wrote:Stay tuned...I just ordered a Grundfos Alpha to try on my system. I have a noisey 007 paired with 4 small zones that should be a good candidate.

With 4 zones and one circulator feeding them, the Alpha should work great. I assume you have temperature regulating valves on each zone to modulate them. Either that, or zone valves.

Zone valves....and no pressure bypass either. When two zones are calling, and one shuts off, the zone valve makes a nice "bang" when it closes thanks to the high velocity. The only reason I have lived with it this long is that those zones don't cycle very often, and a removed one of the return springs in the zone valve to slow it down when it closes.

I run a Alpha on a tiny 10' (4' & 6') of fin tube loop. The Alpha is plugged into a wall outlet and runs 24/7 and the Alpha reads 1 gpm drawing 9 watts if I recall right. The pump is on 1/2" PEX loop...only thing that is 3/4" is the fin tube itself. The loop is at the lowest level of the house which is a basement entry/family space of less than 500 sq.ft. with good amount of windows and with open stairs to upper level and sinking cooler air that is non stop flowing down to the lower level. One other change was to block off all the duct work supply and returns. Air returns were the worst idea with the open stairs as that would only hasten the descent of cooler air for the short duration of the forced air blower cycle.

It is now like I have small stove down there radiating 24/7 but w/o any added fuss.

It has been operational for just one heating season so far and not using a t'stat and has rarely caused the plug to be pulled.

I was just at a taco class at my local sid harveys and the taco 007 will not be manufactured after 2 years or so. The are going to delta p and t ecm pumps. The delta t pump seems like it will do well.

ziggy87 wrote:I was just at a taco class at my local sid harveys and the taco 007 will not be manufactured after 2 years or so. The are going to delta p and t ecm pumps. The delta t pump seems like it will do well.

I'm not surprised that a Taco class would emphasize the superiority of Delta-T. Taco really pushes their Delta-T variable speed circulators. After reading their literature and discussions on it, I was also hook, line, and sinker sold on Delta-T, until I did a lot of serious thinking about it.