SMC Comet 2 recirculation pump

[Fred23]

Hi,
I recently moved into a house which has an SMC pump, a Comet 2 130-20B, fitted as a hot water recirculation pump, see attached photo. Does anyone have operating instructions for this pump they can send me, or advice on its operation.

It appears to require more than just a supply to the pump in order for it to run. I do know it is capable of running because I have heard/felt it, but I can’t work out exactly what conditions cause the pump to run. It doesn’t have any other electrical connections other than the supply (which is switched from the hot water timer on contact).

Any help appreciated.

 

[ReJect]

I would have thought it being a hot water recirculating pump it just needs power, often from a timer to avoid wasting electricity and also heat loss on pipe loop at periods while no hot water being used.
The purpose of that pump, if you don’t already know, is to have hot water in a loop so that any draw off taps have near instant hot water due to the loop being close.
It won’t work simply because a tap is opened. Shower pumps are different

 

[ianmcd]

It is a Bronze pump and can be wired in lots of different ways, we will need more information of what controls it has etc

 

[Fred23]

Thanks for your responses. The pump is being driven from the H/W on programmer contact (terminal 6 on the Y plan standard wiring scheme). There is no timer in the circuit and when the H/W is on I can measure 230V on the pump terminals even if the pump is running, so I figure that there must be a sensor within the pump itself which is causing it to start and stop. The pump does work - I have heard and felt it running - but I can’t figure out what causes it to run.

 

[endecotp]

I can measure 230V on the pump terminals even if the pump is running, so I figure that there must be a sensor within the pump itself which is causing it to start and stop. The pump does work - I have heard and felt it running - but I can’t figure out what causes it to run.

Did you miss a “not” - “even if the pump is NOT running“?

My guess is that you may be feeling the water flowing to the tap making the pipe vibrate, not the pump running at all.

It would be pointless for the pump to have a sensor inside it; it needs to anticipate demand for hot water e.g. with a timer or a motion sensor in the bathroom or something like that.