Where a manufacturer's recommended tyre pressure is not available, this formula will allow you to calculate the approximate tyre pressure for your caravan.
(MTPLM Kg) x (Max tyre pressure in psi)/((Max tyre load Kg) x (Number of wheels)) = Running tyre pressure in psi
Example:
Single axle so 2 tyres
Max tyre press = 65psi (written on the tyre wall)
Max tyre load = 600Kg (written on the tyre wall)
MTPLM = 950 Kg (see plate on caravan chassis)
950kg x (65psi/(600kg x 2)) = 51.46psi