Grundfos Magna3

SpottsBros

Im installing a 3 zone radiant floor system on a greenhouse in CO with a NTI TFT340 boiler. My wholesaler has specified a Grundfos Magna3 circulator at around 3x the cost I would expect. Is there a huge advantage to this circ over say just a 0014?

ScottSecor

Depending on application, the Grundfos will reduce energy consumption substantially. Also runs much quieter. I've read energy use is typically one half to one third of traditional circulator. We use them often and are very pleased.

ScottSecor

Just re-read your post and noticed there are three zones. With the Magna 3 the pump will automatically slow down and speed up based on how many zones are calling for heat.

SuperJ

Large variable speed pumps aren't cheap but are very capable. Sometimes you can save some money by designing around the capabilities of the pump. Eliminate bypasses and simplify controls.

Grundfos offers some pretty advanced control modes. They also offer the option of BACnet control which is awesome for me.

SpottsBros

SuperJ said:

Large variable speed pumps aren't cheap but are very capable. Sometimes you can save some money by designing around the capabilities of the pump. Eliminate bypasses and simplify controls.



Grundfos offers some pretty advanced control modes. They also offer the option of BACnet control which is awesome for me.

OK this makes sense. If this circulator simplifies my piping then it has value. Smallest loop is 5-346 foot 5/8" loops heating a 50x40 insulated slab. But if I cant switch to a simple circulator and have the same results then Ill buy the Magna3

Zman

If you post the entire design, someone would be happy to check the sizing. The magna 3 may be oversized. It depends on the system size and which model magna 3.

gennady

You can check Magna1, if sizing allow. Simplified interface and less functions, but 1/2-1/3 of the price of Magna3.

hot_rod

I have a few of these solar Magnas on the shelf, new in the box, 240 volt and they will take a PWM input from solar, or other controllers. $150.00 plus shipping if you are interested in a bargain circ. Includes iso valves, gauge and insulation shell.

Steve Thompson (Taco)

If the Magna 3 specified is the 32-100 or the 32-60 model it hasn't been available for quite some time (Magna 1 is available). The smallest Magna 3 available that I'm aware of is the 40-80 that would slow down enough to do the job but as others said is overkill.

Us (Taco), Armstrong and Xylem all have 115 volt, 180 watt ECM's locally available that would do the job (Wilo Stratos is only available in 230/1/60).

Savings - I've seen as high as 80% believe it or not, however payback isn't as good as you might expect as our cost of electricity is typically low (depending on where you are located of course).

Note to Hot Rod: Careful about posting the price of your solar pumps - wouldn't want to see you get in trouble.

hot_rod

Thanks Steve, the pumps are from a personal stash, not related to Caleffi or my day job I should note that from now on.

Zman

@SpottsBros
I would take @Steve Thompson up on his offer.
I love to see the manufactures step up.

Steamhead

Zman said:

@SpottsBros
I would take @Steve Thompson up on his offer.
I love to see the manufactures step up.

This.

Rich_49

SpottsBros said:

SuperJ said:

Large variable speed pumps aren't cheap but are very capable. Sometimes you can save some money by designing around the capabilities of the pump. Eliminate bypasses and simplify controls.



Grundfos offers some pretty advanced control modes. They also offer the option of BACnet control which is awesome for me.

OK this makes sense. If this circulator simplifies my piping then it has value. Smallest loop is 5-346 foot 5/8" loops heating a 50x40 insulated slab. But if I cant switch to a simple circulator and have the same results then Ill buy the Magna3

Is this what's installed for the whole job in a 2000 sf building ? Is there Glycol in the system , if so , what is the % ?