Air Tank Drain Valve

Greetings!!

In the process of draining my rear air tank I noticed a leaking drain valve which is located in the engine compartment. It has an air line connected to it that leads to the air tank. This was confirmed by spraying a soapy solution on the valve.

Is this as simple as removing and replacing with a new one? I know that I will need to drain the tank first and will not need to crawl under the coach.

Is a replacement easily attainable?

Thanks for any feedback.