Drain valves

I am a new RV'er. I purchased a Torque T32 toyhauler in the fall and haven't used it yet but am getting ready to do so. Under the RV there are drain valves. I see a hot and cold (red/blue) I assume the red is for the hot water heater and the blue for the fresh water tank? I also see a larger ball valve further back that is already in the open position, I have no clue what this is. Can anyone help me out with my lack of knowledge?

The red and blue valves that are next to each other are your low point drains...to drain the water out of the plumbing.

Some say it is a good idea to bypass the water heater before you open the low point drains so that the crud in the bottom of the water heater won't flow through the pipes.

Red is the hot water pipes...blue is the cold water pipes.

The other drain valve you found is the fresh water tank drain.

JohnD said:

The red and blue valves that are next to each other are your low point drains...to drain the water out of the plumbing.

Some say it is a good idea to bypass the water heater before you open the low point drains so that the crud in the bottom of the water heater won't flow through the pipes.

Red is the hot water pipes...blue is the cold water pipes.

The other drain valve you found is the fresh water tank drain.

Click to expand...

Thanks John. Much appreciated.