What size pump for 2 boiler system?


Old 01-18-14, 10:33 AM
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What size pump for 2 boiler system?

About 10 years ago a friend helped me install a double boiler system in my big, old house. It's basically 2 Weil-McLain GV boilers in parallel according to a design supplied by WM.

I recently hired a plumber to take a look at it because I was worried we had made a mistake and may have shortened the boilers' lives.

The plumber installed a pump that we had left out. It basically is installed after the two boilers and before the zone circ pumps.

The problem is that this guy installed a BIG pump. It's a 1/8hp Taco, and when it's running it pushes hot water past all of the existing zone pumps when they're off!

I must admit that I guess it is worth having a pump in that spot-- the system has always worked, but the water in the zones does get hotter with the new pump.

Do you guys think I should just replace it with a run-of-the-mill circ pump? Considering that the plumber charged so much to install the big pump should I ask him to at least put in a new one w/o charging labor? (I'm sure he can't exchange a used pump, also I imagine that we'll have to adapt down and use new flanges.)


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Old 01-18-14, 01:06 PM
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Max, this isn't making any sense at all.

If you have individual pumps for each zone, there's no need for another.

Do you still have the information that W-M supplied you?

If so, is there a way you can post that information?

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