not all RVs have blue/red water lines. FR has changed them throughout the years.
my '07 Roo has the blue/red but later models have plain translucent ones for both cold and hot.
you need to look under the trailer to find the low point drain discharge tubes.
newer ones have caps on them but my '07 Roo has open ones with the valve just above them, inside and under the sofa.
and Zoe the Wonder Dog(R.I.P.)
'07 Roo 23SS pushing an '07 Chevy Avalanche
Equalizer WDH and Prodigy BC