I have a recirculating hot water system that is recirculating too fast and is losing a lot of heat. The pipes are in interior walls with pink insulation, but they are not directly insulated.

The original installation had a pump that ran 24/7. I have turned the pump off and the system is still recirculating because of gravity convection.

The furnace is a gas boiler with a computer in it. The unit has a connection for optimally controlling a recirculating pump. The pump is not currently connected to the boiler.

The problem is that the system recirculates quite quickly even with the pump turned off. I think I need some kind of heat trap to stop the convection flow. But this trap needs to be strong enough to stop the flow in a recirculating loop. (I may have a trap already, but it isn't stopping the convective recirculation).

Once the convection is stopped I can use the furnace controlled pump. The furnace control will run the pump about 3 min out of an hour and shuts it off over night. My goal is to get the system to completely shut off at night.