Is the 007 Overkill in HWB Installs Using Zone Circulators?

In residential 3/4" copper Hot Water Baseboard installs utilizing multiple individual zone circulators, is the Taco 007 overkill? I believe this to often be the case, and I believe the 005 would be better suited for many to most such applications wherein the desire on a zone to zone basis is to only move between 2 and 3 GPM (corresponding to 20,000 to 30,000 BTUH). In fact, for many zone loops even the 005 is overkill.

Potential advantages for the 005 include:

Less initial cost, less system wear and tear, less electrical consumption, and less noise.

Many zoned systems are overpumped. The 3 speed circulators help, assuming you don't just set them all on max.

Rob R. wrote:Many zoned systems are overpumped. The 3 speed circulators help, assuming you don't just set them all on max.

x1 It's like owning 3 pumps instead of just 1.

but do you install 3 speeds on every loop, set them to low and never use the higher settings?

The price difference isn't that much. The operating cost isn't that different. The harshness to the system can't be that much if it is installed correctly. Trying to find a 005 in times of crisis would make the 007 a winner hands down. IMHO

Scottscoaled wrote:The price difference isn't that much. The operating cost isn't that different. The harshness to the system can't be that much if it is installed correctly. Trying to find a 005 in times of crisis would make the 007 a winner hands down. IMHO

007's and/or 3-Speeds work well in emergencies, where available space in the repairmans toolbox is limited, and where price, electrical consumption, and sizing the proper circulator are of little to no concern at the moment, but why choose one of these when most people don't live in lifeboats (a euphemism for perpetually living in an emergency situation)? For those who don't live in lifeboats, why not plan ahead and install a better matching circulator for the job right up front? Why choose up front and then perpetually live with a circulator prided in having sufficient umph to get people (meaning here also the repairman) out of emergencies no matter what system the repairman encounters at the spur of and in the heat of the emergency moment, when there is no such emergency?

hotblast1357 wrote:but do you install 3 speeds on every loop, set them to low and never use the higher settings?

This topic is about a system w/ zone valves and only a single pump.

But as for zone pumps one may select any speed for any pump, let your thoughts run wild.

McGiever wrote:

hotblast1357 wrote:but do you install 3 speeds on every loop, set them to low and never use the higher settings?

This topic is about a system w/ zone valves and only a single pump.

That wasn't my understanding. If you are using zone valves, get an "Alpha" pump.

lsayre wrote:n residential 3/4" copper Hot Water Baseboard installs utilizing multiple individual zone circulators

Scottscoaled wrote:The price difference isn't that much. The operating cost isn't that different. The harshness to the system can't be that much if it is installed correctly. Trying to find a 005 in times of crisis would make the 007 a winner hands down. IMHO

Most baseboard systems are pretty tolerant of higher velocities. The might be a little more noisy, but that is about it. Cast iron radiation is a different story, it is a fact that the radiators actually put out less heat if overpumped. I would not suggest using an oversized pump for 10 years just because it might be a model that is easier to find. If you need to buy pumps for a new system, get the right ones.

This thread is about systems with each zone having its own circulator.

I used Grundfos 3-speed pumps on my brother's system. Some of them are set on low, some are on high. Depends on the size of the zone.

To Scott's point, the energy savings is very small from one speed to another.

yep,
sure enough he is referring to zone circulators. But his own install is w/ zone valves and that was what came to mind immediately for me.

McGiever wrote:yep,
sure enough he is referring to zone circulators. But his own install is w/ zone valves and that was what came to mind immediately for me.

True enough! And although it is not relevant to this thread, I'm considering an Aquamotion AM5-FV1 as my next circulator (which may be a decade or more from now). The Aquamotion AM5-FV1 (where -FV1 means with built in check valve) is the closest Aquamotion circulator to the Taco 005. It has a tad more output, so its pump curve with check valve is very close to that of the Taco 005 without check valve. I've ran the figures and it will deliver all that I need for my 4 zones with a single circulator.

The Aquamotion AM7 is their match to the Taco 007, and just as for the AM5 it has a tad more output, so its curve with the -FV1 option is a close match to the 007 without check valve.

Just as for Taco, they do not publish curves for circulators with the check valve installed, but I asked them to send me hand drawn curves.

The thread relevance comes in when I add that my research into a single circulator that is adequate for my 4 zones is what inspired my conclusion that if it is adequate for 4 zones it should surely be adequate (or even perhaps overkill) for single zones. The reality however is that even though it actually gets easier for a circulator to deliver higher GPM's as more zones are added/opened to it (NOTE: must be in parallel) whereby friction head decreases and thereby GPM's increase, even with this knowledge you can't simply make an arbitrary statement as I just did (that if its good for 4 zones it will be good for 1 zone) without crunching the numbers and matching them to the pump curve. I think I just slapped myself.

I have been watching this thread with much interest and had my own slapping myself moment. I studied the gmp charts and such some years back also. My system however was not "Standard" and I used a taco 0012 in an injection system install with a Grundfos 3 speed feeding it. The 3 speed is set at low.....and I have the isolation ball valves choked down.....I think I will make some changes when the time comes.....

Kevin

And don't bother jumping all over me for throttling down a calculator.....been there already.

Kevin

Taco has a new 007 on the market. ECM motor.

http://www.taco-hvac.com/products/variable_speed_products/007e/index.html