Do I want a smart ECM pump for my boiler loop?

rsilvers

I am redoing a system with a G215-5, It was one loop with a mix of undersized 1-1/4 and even 1 inch shared pipe, but I am making it primary/secondary with a 1.5 inch Caleffi hydro-seperator.

This is a 180,000 BTU system, and the burner kit came with a Grundfos 3-speed pump just barely capable of up to 18 GPM (at basically no head).

Presumably, if I install this free pump, I would set it to the highest speed so that it can try to do 18 GPM such that it can move 180,000 BTU at a 20 degree drop.

If I instead used an Alpha smart pump, would it ever know to reduce wattage and save power? If so, would the power savings pay for the $165 pump? (we have 0.29 electric rate).

hot_rod

It’s an ECM motor, so it will use 50% less electricity in any fixed speed mode also.
Does the pump curve show it can move the flow you need?
Do you need 18 gpm?  There is no requirement to run a 20 delta. Allow a wider delta and gpm requirement drops.
what is the heat load you are designing to?

rsilvers

Ok, I will do it. I might stick the fixed motor on zone that is not used much.

Alpha1 says it can do 21 GPM and 12 GPM at 7.5 ft head, whereas the free included pump says 18 GPM and 12 GPM at 2 ft head.

pecmsg

rsilvers said:

I am redoing a system with a G215-5, It was one loop with a mix of undersized 1-1/4 and even 1 inch shared pipe, but I am making it primary/secondary with a 1.5 inch Caleffi hydro-seperator.

This is a 180,000 BTU system,

If I instead used an Alpha smart pump, would it ever know to reduce wattage and save power? If so, would the power savings pay for the $165 pump? (we have 0.29 electric rate).

Thats a lot of BTU's!

rsilvers

10,500 square foot house.

PC7060

rsilvers said:

10,500 square foot house.

Wow

rsilvers

Plus a 3500 square foot pool house, but that has its own propane furnaces and gas fireplaces. 

PC7060

I have a Alpha2 on my system; performs very well and the status display for GPM and wattage are very useful. Make sure you put a Caleffi DirtMagPro on the return side of boiler to capture the magnetite before it hits the Alpha2 (assuming the pump is on supply side in a pumping away  configuration). The magnetite vigorously stick to the rare earth magnets in ECM will reduce performance over time if not cleaned from the system. 

rsilvers

I have a Dirtmag on one system.

mikeapolis

May want to check out the Taco VT2218
https://www.tacocomfort.com/product/vt2218-ecm-high-efficiency-circulator/

PC7060

rsilvers said:

I have a Dirtmag on one system, but the magnets seem awfully weak.

The pro added a axial magnet to the previous generation so now two mags. 

rsilvers

mikeapolis said:

May want to check out the Taco VT2218
https://www.tacocomfort.com/product/vt2218-ecm-high-efficiency-circulator/

Wow that is fantastic. I want. Only issue is the cost and I am putting thermometers on every return. I was going to just change the Delta-P mode until I saw about a 25 degree drop on the return.