While putting in a new hot water heater, I had to deal with the water pump and associated connections and parts. The system has an accumulator tank and my understanding is that the pressure in that tank provides the instant water pressure and supply for the coach and then the pump kicks in when the system pressure drops to the cut-in setting of the pump. The accumulator tank specs call for the pressure in that tank to be 2psi below the pump cut-in setting.

While the tank was out of the coach, I checked the pressure in the tank and there was 0. I think it's been that way since we bought the coach. I aired it up to 38psi and it was reinstalled. I can tell a difference in the water the water delivery acts and it all works as described above. I can tell when the pump kicks in.

The water pump specs, a Headhunter Mach 5, say the system can work either with or without an accumulator tank. The pump will get to full speed and pressure instantly on demand without the tank. With the tank, it will do the same but only when the system pressure drops to 40psi.

With no air in the tank, we've never had any issues at all with water pressure. It's always been instant at full pressure.

So, what is the value of the accumulator tank in this system?