Grundfos Alpha Installed

After a few other discussions (see below) in the last week or so I finally decided to do something about the noisy zones in my house. I had a Taco 007 serving 4 small zones, and it was easy to hear the water going through the pipes and occasionally the zone valves would rattle the pipes when they closed. A differential pressure bypass valve would have been a solution, but I decided to replace the ~15 year old circulator instead. It was a simple swap, and while I was at it I replaced the circulator that serves my EFM with a Grundfos 3-speed unit. My thinking was that the short run of 1.5" piping had very little resistance, and there is really no need to sling 20 gallons per minute between the two boilers.

The install would have been easier if the guy who installed the oil boiler had left more room between the circulators, and squared the flanges...but rather than repipe everything I just alternated the way the circulators face. I left the Alpha on Autoadapt, and set the 3-speed unit on low. One zone with 3/4" piping opened, and the Alpha displayed 4 gpm and 19 watts. A second zone opened, this one with 1/2" piping...and the Alpha displayed 5 gpm and 24 watts. Very quiet, and I made multiple zone valves open and close in an attempt to get them to "bang" closed like I have seen in the past. Nothing, just silence. So far so good.

Is the 007 Overkill in HWB Installs Using Zone Circulators?

Grundfos Alpha Circulators 'Auto Adapt' Program Question

Rob, it sounds like a winner in your application. Glad you got rid of both the velocity noise and the water hammer.

I would follow suit, sans that my differential pressure bypass valve (DPBV) is not only serving the purpose of eliminating velocity noise and water hammer, but it is also serving double duty as my only means to mitigate the problem of having our boiler get slammed with very cold returning water as would happen for the situation whereby all zones are sitting along their respective cold outside walls and in the process getting quite cold while waiting for their T-Stats to finally activate, and then finally one is zone valve is activated and a rush of cold water from that cold zone suddenly heads at full speed toward the hot boiler. Happily, in such a scenario wherein only one zone valve opens after a prolonged period of all of them having been closed, it just so happens that in the same case the DPBV opens to its fullest extent dumping a goodly amount of hot boiler temperature water into the cold returning stream, so that when it hits the boiler it is not straight cold zone return water hitting it. Fortunately for me, I've never seen more than two of the four zone valves opening at exactly the same time, as if all four of them ever opened simultaneously the DPBV would remain closed, and then (for this, my worst case scenario) all four zones worth of cold return water would simultaneously slam the boiler unmitigated. This issue may preclude me from ever having the ability to utilize a single "speed varying" circulator, be it Delta-P or Delta-T.

But in your case of having a primary circulating loop and a secondary of circulator fed zones, there is no such worry as for my case.

With all 4 zones open, what GPM reading did you see?

lsayre wrote:With all 4 zones open, what GPM reading did you see?

I haven't tried that yet. The house was pretty warm already - I didn't want to explain why I had the heat on.

Wow, those circulators are close together!!!

I am a big fan of the Grundfos 3-speeds, as heating loads vary through out the season (includes the indirect) it is a nice option to be able to 'tinker' with flow rates.
As I mentioned in a previous posts, I like wise have an Alpha pump and have been 'tinkering' with it on a couple different zones here. Last season it ran around 8 watts and at barely 1 gpm on a new small zone and performed fantastic.

Got a Bell & Gossett Ecocirc Vario pump with 'stepless speed control' sitting on the shelf I'm itching to try also.

Rob R. wrote:I haven't tried that yet. The house was pretty warm already - I didn't want to explain why I had the heat on.

This pump aquisition sounds like it was one of those "covert aquisitions" I sometimes do here. I don't feel the need to explain why I picked up that IR temp sensor just so I can take a temp on the stove pipe or the stove side so I don't mention it showing up on the cc statement if she doesn't happen to ask. (Or that back up 53* wedge I found online just in case the magic leaves the one I have in my bag.)

McGiever wrote:Got a Bell & Gossett Ecocirc Vario pump with 'stepless speed control' sitting on the shelf I'm itching to try also.

I will be waiting for the reports on that one! Do keep us informed on it. Why did you choose the Vario over the Auto?

lsayre wrote:

McGiever wrote:Got a Bell & Gossett Ecocirc Vario pump with 'stepless speed control' sitting on the shelf I'm itching to try also.

I will be waiting for the reports on that one! Do keep us informed on it. Why did you choose the Vario over the Auto?

I got it at a good bargain.
I wouldn't mind getting a Auto someday.
They are both made in Hungary.

Seems like B&G is aware of the concern about metallic debris getting stuck to the magnet. Their brochure says the following:

the anti-block technology separates the main fl ow of
the pumped media completely from the permanent
magnetic parts. it is virtually impossible for the ecocirc
auto or vario to block-up even in an old open system.

Rob R. wrote:Seems like B&G is aware of the concern about metallic debris getting stuck to the magnet. Their brochure says the following:

the anti-block technology separates the main fl ow of
the pumped media completely from the permanent
magnetic parts. it is virtually impossible for the ecocirc
auto or vario to block-up even in an old open system.

I guess that means it's a bit better than the Taco???

I don't know why they keep referring to "Old Installs". What about all those people buying NEW radiators and installing them?

I'm pretty curious about how these new fancy pumps work with iron radiators. I have one or two laying around and would like the option of using one of these pumps to avoid deadheading into a bunch of closed thermostatic radiator valves (TRV's).

-Don

I think that a system that has been well flushed and has a strainer should be no problemore for the pump, but time will tell if I am wrong. There is no strainer on my system, but the 50+ yr old piping and radiatorsee have been thoroughly flushed. The old water I drained out last week was very clean, and still light purple from the treatment I added last yesr.

Rob R. wrote:I think that a system that has been well flushed and has a strainer should be no problemore for the pump, but time will tell if I am wrong. There is no strainer on my system, but the 50+ yr old piping and radiatorsee have been thoroughly flushed. The old water I drained out last week was very clean, and still light purple from the treatment I added last yesr.

What treatment did you use, Fernox?

-Don

Strainer that I installed was on new system with old 1959 boiler I didn't know what might have been inside.
Yes, I flushed it but...one bad piece of chit makes it to the pump(s) and it is trouble.

StokerDon wrote:

Rob R. wrote:I think that a system that has been well flushed and has a strainer should be no problemore for the pump, but time will tell if I am wrong. There is no strainer on my system, but the 50+ yr old piping and radiatorsee have been thoroughly flushed. The old water I drained out last week was very clean, and still light purple from the treatment I added last yesr.

What treatment did you use, Fernox?

-Don

No, I was an off-brand that I got at the supply house. Can't remember what it was called...just that it was purple.