Hot water circulator sizing

[Daniel Collick]

Bell and Gossett pl36 or pl55 is what I would put in.

B&G website states those are cast iron body pumps for closed systems. I’d need a lead free brass or SS body pump for a potable system.
It’s ok if I don’t overcome 100% of the temp drop. Stored temp is 128 degrees for the whole building, so even if I lost 20 degrees at the fixtures farthest from the source, that’s still a usable temp for residents.

 

[Jeff H Young]

id work out the pump sizing and type with the manufacture and install circuit setters on all the return lines where they enter the main return and then keep them closed off to where flow just barely maintaIned temp and run pump constant. ive never ballanced one out but you want the flow set to minimum so you dont have excess wear on the piping or inadequate flow on other circuits. but i dont think you want those circuits run wide open

 

[Sponsor]

 

[John Gayewski]

B&G website states those are cast iron body pumps for closed systems. I’d need a lead free brass or SS body pump for a potable system.
It’s ok if I don’t overcome 100% of the temp drop. Stored temp is 128 degrees for the whole building, so even if I lost 20 degrees at the fixtures farthest from the source, that’s still a usable temp for residents.

No. The Pl series of pumps is just that a series in that design. They have them in cast iron and in bronze for potable water.

I think the 36 or 55 would get you close to 20 degrees. The 55 for sure would, but the 36 might not. The grundfos would not in reasonably sure about that.

 

[John Gayewski]

 

[John Gayewski]

 

[John Gayewski]

id work out the pump sizing and type with the manufacture and install circuit setters on all the return lines where they enter the main return and then keep them closed off to where flow just barely maintaIned temp and run pump constant. ive never ballanced one out but you want the flow set to minimum so you dont have excess wear on the piping or inadequate flow on other circuits. but i dont think you want those circuits run wide open

Not sure if you've tried calling a pump manufacturer in a while, but they give you a phone number if a rep. (that is if they get back you you) and then you hope the sales reps knows what he's talking about or gets back to you at all. Taco and Bell and Gossett are pretty OK with taco being the best at customer service I think. They just don't have the variety of products.

 

[Daniel Collick]

Not sure if you've tried calling a pump manufacturer in a while, but they give you a phone number if a rep. (that is if they get back you you) and then you hope the sales reps knows what he's talking about or gets back to you at all. Taco and Bell and Gossett are pretty OK with taco being the best at customer service I think. They just don't have the variety of products.

100%
I got in touch with one today. I gave him my scenario and sent him the specs on the existing Grundfos model. He agreed with the same concerns you pointed out regarding noise, circ pipe size, and the possibility of leaks developing due to increased GPM.
He’s going to give me a couple B&G options that increase GPM respectively.
I’ll update you with his comps for your input.

 

[Daniel Collick]

Bell and Gossett pl36 or pl55 is what I would put in.

B&G sales rep is recommending either of these 2 options:
NBF-10S/LW
Or
NBF-18S

 

[John Gayewski]

B&G sales rep is recommending either of these 2 options:
NBF-10S/LW
Or
NBF-18S

Let us know how it works. Mainly the delta t.