Loud Circulating Pump (Steam Boiler)

itsuke

Hello everyone,

I had some work done on my Steam Boiler which included the replacement of the old circulating pump as it was dead. The old pump was a Taco 007-F5-7IFC. The service tech brought out the same pump but the one without the IFC (007-F5) and its making some weird loud noises.

It's important to note that these noises do not start immediately after the pump goes on (call for heat) but after the boiler has created steam for the condensate to return and run on that baseboard loop where the circulating pump is connected.

I have tried the usual of getting any air out of the system to no avail. I attached a short clip so you all can hear what it sounds like. Could the flow check missing in the new pump cause this? The two pumps have the same HP rating of 1/25.

Link to video:

https://imgur.com/a/z8OzdCb

Link to the old pump: https://shorturl.at/fkYWo

Link to the new pump:

https://shorturl.at/Medx4

I would appreciate any help with this.

Thank you all and happy holidays.

Joe Mattiello

try increasing the pressure on that loop.

If your pumping condensate you might be flashing because of high vapor pressure.

itsuke

@Joe Mattiello how would I increase the pressure? This is a loop running below the water level of a steam boiler, the return side feeds the loop.

Thank you

Ironman

That’s the wrong pump for that application. A wet rotor circulator should not be used, nor should it be iron. You should have a bronze or stainless three piece circulator like a B&G series 100 or the Taco equivalent.

EBEBRATT-Ed

Bronze or stainless pumps are expensive but will last a lot longer. Cast Iron pumps are not the best for an open system.

Can you take some still picture of the piping and pump and how it connects to the boiler?

Don't know if with the check valve out it may have increased the flow causing it to cavitate?

itsuke

@Ironman can you explain why? also, could you advise on a model number pump i should use?

thank you for your help

itsuke

@EBEBRATT-Ed yes, I'll attach some pics below. What do you mean by "open system"?

I am wondering the same regarding the check valve- there shouldn't be any backflow but see the pictures and maybe you get a better understanding.

Thank you.

IMG_8237.jpeg

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ethicalpaul

he means open to the atmosphere as all residential steam is.

I am concerned about that rise before the pipe gets to the boiler. Is is close to the water line?

The circulator might be sucking air