Hello - I have a boiler for my heat and hot water. My plumber wants to replace the pump on the boiler to a more powerful model that pushes more water through the system which he says will provide more heat. He also wants to rewire the controls to give priority to the water heater over the other heat, which will provide almost the same benefit as adding an on-demand water heater. All of that makes sense to me. But he also wants to add a 2nd pump just to the water heater which he claims will push even more hot water to the water heater which will do a better job of heating the water quicker. But if both pumps are the same capacity, will the 2nd pump really do anything? It seems the 2nd pump will only get as much water as is pushed by the 1st pump, so there would be no benefit and lots of cost to adding that 2nd pump. Am I missing something?

Unless you are living in a multi-level 20,000 sq/ft home I see no need for two. How bad was it with the one smaller one you have now. What is not good on the current set-up?