New one to me. Is this some kind of circulating pump?

Need to see more but it looks like a circulating pump that makes the system have instant hot water to all taps in the home .
This looks like a pump that is used on a hot water heating system and is larger then is usually used .
Roy Cooke sr… Royshomeinspection.com

Bell and Gossette circulating pump.
Usually used for boilers.

Is the turn valve at the bottom of the copper the main shutoff for the whole house?

If so, maybe the house has low water pressure and the pump is used to assist with flow.

If the pump is only on the hot water line, then I could agree with Roy about on demand.

It would be a poor attempt, though. Still going to be cold water from the pump to the faucets.

On demand usually requires a unit under a sink or vanity, right near the faucet it provides for, correct?

Just a thought. If it is being used as a circulating pump that is always on or turned on in response to a temp sensor somewhere, feel the “cold” water inlet to the water heater. It should be near the same temp as the outlet. when this method is used, a recirculate line needs to be run from a remote fixture to make a “loop” in the system that is always Hot. By the way, that size pump would seem to be overkill in a residential system.

This is an old circulating pump that requires periodic oiling at three small ports on the top.

Is this connected to a boiler?

If so, this pump is used to take heated water from the boiler and send it into the water heater for domestic use. It’s called an in-direct water heating system. The boiler heats the water first then the electric water heater stores the domestic water.

That is a circulating pump for the water heater so that hot water is distributed through out the house quicker. They are usually always running.

Nice graphic David.

I have a question. Would there need to be a TPR on both the boiler and the storage tank?

It had a electrical controller that had temp settings on it, much like a controller you would see on a attic vent fan. I figured it was a heat circulating pump. Thanks!


I asked because I didn’t see one in your graphic.

My home boiler has one on the side of the cabinet.

Sorry I disagee you do not need one on the storage tank if it is being fed from a hot water boiler .
The storage tank water will not get to steam and raise the pressure above the town supply pressure.
There is a pressure one shown on the Boiler system and It is required.
Shown just above the pump next to the tap.

Roy Cooke sr… Royshomeinspection.com

Roy I think that’s may be a pressure reducer for the fill/makeup supply line. The system also does not have any backflow prevention device shown.

Perhaps the graphic is not meant to be exhaustive in nature.

Of course I will differ to someone with more expertise in this area.

Good pick you are correct sorry .

Roy sr

Look at the bottom right hand corner of my graphic.

It simply states “Pressure relief valve not shown”.

“Look twice, speak once” Thanks David, my bad.:oops:

I suspect the original author had that pointed out a few times before the disclaimer was added. IMHO

Nothing to be sorry about. I’m here to learn with the rest of you. I learn something useful every day I come to this board and appreciate what a great resource this is to HIs.

I usually see these hot water circulators in large homes where bathrooms and such are some distance from the hot water heater. Installed so you can have hot water instantaneously. Energy waster!

David, those are great illustrations. Do you have a preference betweeen the one from Carson Dunlop and the one from Inspection Depot? -Kent

No preference…I like them both. C & D illustrations are black & white and Inspection Depot comes in full color.

They used a bronze body pump which is the first clue that it is for H/W recirc. It is tied into the bottom of the tank which is fine. Like Ray mentioned, larger homes usually with runs of 100’ from the heater require recirc systems. This also puts less wasted water into the town sewer or septic, and saves energy