Hot Water Recirculating Pump - Pressure Switch

[Kevin-NC1]

I'd like to install a retrofit hot water recirculating pump. My plan is to use one of the retrofit thermal bypass valves between the hot and cold water lines at the faucet farthest from the hot water tank, using the cold water supply line as the bypass return path. An example of the type of valve I'm considering can be found here: Valve

I understand that the valve slowly closes as the water in the hot water line increases to ~ 95F. If I am running a recirculating pump that pumps hot water to the faucet and dumps the cooled "hot water" to the cold water supply line, when the valve begins to close, what prevents the recirculating pump from eventually being "dead headed." How do these types of valves and recirculating pumps handle the valve closure without a problem? Is a pressure switch part of all recirculating pumps or do they have their own internal bypass? Trying to understand the theory behind how all this works and not cause burst pipes or ineffective recirculation system. Installing a dedicated return line is not an option.

Thanks,

KK

 

[Fitter30]

A timer is used to cycle the pump. The recommended pumps have a timer built into the pump housing.

 

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[John Gayewski]

No recirculating pump will burst a pipe. Unless your pipes are made of paper towels.