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HI my name is Robert...
Are you using a hose going into the antifreeze? Most set ups will have a three way valve near the water pump, you turn the valve and then it allows it draw from a hose that is hooked up to the pump. Sometimes you can loose prime, try and hold the hose up high with a funnel and pour the antifreeze in the funnel, also try to loosen the outlet on the water pump, briefly turn the pump on and make sure you have flow. The pump can become air bound. Make sure you also have over 12 volts DC at the pump, if the voltage was low the pump could still run but not produce water.
As far as the water heater cold and hot shut, valve handle running with the pipe and the bypass closed valve handle running against the pipe, sounds like you have that correct.
Once the antifreeze gets going you will feel air before the antifreeze, also dump about 1/2 cup down each sink, shower etc..
IF you still need more help please let me know, follow ups are included.... Robert
I sent you a phone request if needed, not sure you saw my answer prior to wanting to do the call...