grundfos alpha 15-55

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webie

Minister of Fire
Hearth Supporter
Feb 21, 2009
651
Wisconsin
I am looking o replace my taco 007 primary pump on my solo 60 with one of these . Just wondering if anyone was useing one of these pumps and if there are any pros or cons about these ?
 
It makes for a very good replacement for your taco 007. Get's roughly twice the "mileage" at a given flow. Also displays flow and electrical usage. I like it. What sort of storage system do you have?
 
I was wondering on the curves it looks like a bit less gpm but more head pressure so I think I may gain a little flow ,not sure on this only guessing . As far as my storage I have a non pressurized 1200 gal tank and I am running 5 zones running 4 pumps a B&G SLC-25 from the backup gas boiler and then 3 taco 007's on the solo , one for the boiler loop one for the zones and one for the radiant heat loop . My other thought on a replacement pump was a taco 00R . Another question do the flanges match from a taco to the grundfos? My reason for replacement is 2 fold the pump iI have on it now has many miles on it going on its 9th year so it would make a fine backup pump on the shelf and also I would like to increase my flow .
 
These new ECM high efficiency pumps like the Grundfos Alpha (and other brands) are much more efficient in terms of how much electric power they use to pump the same amount of water. And that can add up to surprisingly large savings over the long term.

But, at least in the case of the Alpha, one of the features that you are paying their very high price for is the ability to adjust their pump speed to different loads as zones call for heat and then close. The Alpha (and maybe the others) can keep a nearly constant pressure on the loads as they vary. It doesn't use any more power than necessary to accomplish the required flow. This saves money for electricity and keeps the different zones balanced since the head across each zone doesn't vary so much depending on what the other zones are doing.

So, unless you are replacing a pump which functions in your system to pump under varying loads that can effect the flows through each other, I question whether you are using an Alpha to its potential. Don't get me wrong, I'm planning on using one to drive my radiant zones. I just wonder if their electric efficiency alone can justify their cost.
 
With a grain of salt, an article written by Taco about Delta P pumps which they don't offer :)

In the very near future only ECM circs will be allowed in many European countries, as they are the only ones that can meet the energy standard, see Europump.org.

hr
 
Webie, could you call me this week? I am from northeastern wisconsin myself and I am installing a solo 60. Thanx 920 655=2683
 
yippee the pump is ordered should be here by the weekend , and actually I have ordered 2 pumps a NRF-25 B&G and the alpha . The plan is to replace my zone circ. with the alpha and the boiler charge pump with the B&G . I will be really courious to see whats up with the taco 007 charge circ as something has been going on for a year with this pump . I just dont get the pump action out of it like I use too and it seems to be growling a bit . I will let you all know what I find when I pull this out . The plan Is this weekend. I will be courious too on how this alpha works out for my zones as I have one that ussually under pumps and one that over pumps so will see how this does , I am sure I will be in for a new learning curve comeing up .
 
Yes, please keep us posted if you can. I recently purchased the Alpha but won't be installing it till after the heating season is over. I'm going to be running 3 zones off it.

thx, Pat
 
Well the new pumps are in , Jury is still out yet on how this is all working , I am now on a new learning curve .
This alpha is strange but cool
 
" one zone under pumps" ? If your head requirements are different, and more than one zone is calling, the water will always take the easy route. Changing the circulator is not going to help this.
On multiple zone systems, we sometimes use multiple pumps to zone valve headers to ensure the proper flow where it is needed. Or, uou can also use balancing valves.
 
Chris S said:
" one zone under pumps" ? If your head requirements are different, and more than one zone is calling, the water will always take the easy route. Changing the circulator is not going to help this.
On multiple zone systems, we sometimes use multiple pumps to zone valve headers to ensure the proper flow where it is needed. Or, uou can also use balancing valves.

In all actuality I have the opposite problem , This house's heating system was originally put in to be supported by a small wood boiler running at 160 degrees . Good for me now with storage ,but hard to control with boiler temps in the 180's . Last night with the tank charged and boiler out I ran on auto adapt on the alpha . I think its pumping to fast as this morning the top of my tank was at 151 and the bottom was at 144 , there seems to be only about a 15 degree change in return temp . The first trial on Saturday the pump has no problem supporting 4 of my zones running . It kinda pooped out when I kicked in the last zone for the basement that one took quite some time for the water to fully cycle . I am not to worried about this as its rare that I would have all 5 running at one time In most cases here there is only 0-3 running at a time . Tonight I am running on the slow speed setting so far it seems to be doing OK . The return temp seems to be about a 25 degree loss which works here , will see what my tank temps are in the morning . Oh and by the way I have 1200 gals of unpressurized storage and am running a 30% glycol . My only other thought to slow this down might be to use the IFC which I am not now .
 
webie said:
Chris S said:
" one zone under pumps" ? If your head requirements are different, and more than one zone is calling, the water will always take the easy route. Changing the circulator is not going to help this.
On multiple zone systems, we sometimes use multiple pumps to zone valve headers to ensure the proper flow where it is needed. Or, uou can also use balancing valves.

In all actuality I have the opposite problem , This house's heating system was originally put in to be supported by a small wood boiler running at 160 degrees . Good for me now with storage ,but hard to control with boiler temps in the 180's . Last night with the tank charged and boiler out I ran on auto adapt on the alpha . I think its pumping to fast as this morning the top of my tank was at 151 and the bottom was at 144 , there seems to be only about a 15 degree change in return temp . The first trial on Saturday the pump has no problem supporting 4 of my zones running . It kinda pooped out when I kicked in the last zone for the basement that one took quite some time for the water to fully cycle . I am not to worried about this as its rare that I would have all 5 running at one time In most cases here there is only 0-3 running at a time . Tonight I am running on the slow speed setting so far it seems to be doing OK . The return temp seems to be about a 25 degree loss which works here , will see what my tank temps are in the morning . Oh and by the way I have 1200 gals of unpressurized storage and am running a 30% glycol . My only other thought to slow this down might be to use the IFC which I am not now .

Sounds like it will work OK for the most part. I only wanted to run 3 zones with mine, but I'm thinking now about trying all 4. I would have 2 basebaords, 1 radiant, and 1 DHW maker. How did it handle the radiant zone? That would be my biggest concern.

The IFC is supposed to slow the flow by about 10% if I remember the literature correctly. Keep us posted please.

thx, Pat
 
Pat not sure how your radiant is set up but mine is a loop with a taco 007 circulating it . All the grundfos has to do is to inject hot water into this mixed loop . The loop I run at about 120 and it handles it that easily because it kinda sucks the hot water in as it displaces the cooler water its ejecting .
The sweet spot I have found for my system seems to be setting this thing on maintaining the low pressure setting , its like the in between of the slow speed and the auto adapt . this seems to be working well right now as any zone that calls for heat the pressure drop causes the pump to speed up to try to compensate .
 
webie said:
Pat not sure how your radiant is set up but mine is a loop with a taco 007 circulating it . All the grundfos has to do is to inject hot water into this mixed loop . The loop I run at about 120 and it handles it that easily because it kinda sucks the hot water in as it displaces the cooler water its ejecting .
The sweet spot I have found for my system seems to be setting this thing on maintaining the low pressure setting , its like the in between of the slow speed and the auto adapt . this seems to be working well right now as any zone that calls for heat the pressure drop causes the pump to speed up to try to compensate .

Sounds good Web. Have you tried it yet on just the Autoadapt mode?

Pat
 
Auto adapt works good . I don't care for it because I use unpressurized storage its moving the water just a bit to fast for my liking and my whole tank ends up cooling down . The pressure settings are pretty cool because as you have zone openings the pump tries to maintain the same pressure till the pump maxes out . This thing is so adjustable I just dont see why it wont work for you unless you have some really bad plumbing , then I would stick with individual zone pumps .
 
webie said:
Auto adapt works good . I don't care for it because I use unpressurized storage its moving the water just a bit to fast for my liking and my whole tank ends up cooling down . The pressure settings are pretty cool because as you have zone openings the pump tries to maintain the same pressure till the pump maxes out . This thing is so adjustable I just dont see why it wont work for you unless you have some really bad plumbing , then I would stick with individual zone pumps .

I'm sure it will work fine for me as well. My plumbing is pretty simple and when I re-do some of it, it will be even simpler (less fittings, etc) Now I just need to figure out how the boiler loop is going to work efficiently and I'll be all set... I hope !

Pat
 
There is one other thing , This pump doesnt use much power to move water Most of the time its between 10 at idle to about 24 watts, i have to set it on high speed to get it to max at 45 watts .
This is really really wierd
On the pump its self its says min .05 amps and 5 watts ,max .65 amps and 45 watts .
Now isn't it (volts X amps = watts)
I have it pluged into a kilowatt and its reading what the pump says and it will draw .65 amps and 45 watts , How can this be ?
 
webie said:
There is one other thing , This pump doesnt use much power to move water Most of the time its between 10 at idle to about 24 watts, i have to set it on high speed to get it to max at 45 watts .
This is really really wierd
On the pump its self its says min .05 amps and 5 watts max .65 amps and 45 watts .
Now isn't it (volts X amps = watts)
I have it pluged into a kilowatt and its reading what the pump says and it will draw .65 amps and 45 watts , How can this be ?

Not sure, that does sound strange, watts should be higher than amps. Call Grundfos when you get time and see what they say.
 
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