Aquastat

[robsvdp]

I have a tankless Noritz heater with a Grundfos 3 speed pump on a loop (a UPS model). I just purchased an aquastat that Grundfos told me is compatible, but I just can't figure out the wiring. My pump is plugged into the wall, so from the pigtail I have a white, black, and green wire. My aquastat is just one white, one black. How do I wire this in? i know it's staring me in the face, just can't figure it out....
Thanks!

 

[havasu]

The green wire is just the ground, so if it connects to the Grundfos, it is possible that the ground will be connected when attached.

 

[robsvdp]

After staring at the schematic and the pump, I think I take the black wire off the pump "L" connection and splice it to the black wire of the aquastat, and then connect the white wire of the aquastat back into the pump at "L". Anybody have tips / ideas before I try this? Thanks!

 

[havasu]

I'll be honest. I believe many are not replying because the best answer would be to have a qualified electrician do the install so injuries will not occur. If possible, could you take a pic of the installation directions and we might be able to give you our recommendations?

 

[robsvdp]

Good idea - attached is a pic of the pump and the diagram. Thanks!

 

[robsvdp]

So, in case anyone else runs into this, I just did it - removed black wire from pump, spliced to black wire of aquastat, attached white aquastat wire into the "L" from which the black wire came. Works perfectly.

 

[havasu]

That makes sense since it needed to be looped. Thanks for the reply, as I'm sure it will one day help someone else.

 

[chaseme5]

Looking at the guage of the wire, find out how many amps this pump draws. Electrical outlets are rated for 15A 14 guage. The wires in the picture look like they are 2-4 guage. This can be a fire hazzard if that is the case. That means this pump needs a dedicated circuit that has the proper guage wire and correctly sized circuit breaker to support the load.

 

[robsvdp]

Thanks - it's just a very enlarged picture. Those wires come off the pigtail of a three prong plug, factory installed on the pump by grundfos. Looks like 14 guage to me.