Draining water system

Hello everybody, I have just taken delivery of a 3 month old Symbol Auto.and would like to drain all the pipes, the only drains I can find the one on the Whale boiler and the 2 tanks , the auto sleeper book only covers the Truma set up?

the drain valve with the whale water heater drains out under the tank and do have problems not sealing when refilling the system .to sort this problem I turn the valve on and off this cleans the seal .I would not say to leave the drain valve open but see what other people that have this whale water heater say they do

Don't know your set-up, but there are possibly 4 things to empty:
Fresh water tank;
Grey water tank;
Truma hot water boiler and all pipework; (all taps open).
(if separate) "cistern" tank supplying water to flush WC.

The WC cassette is usually left clean, with some Elsan or similar in the small amount of water; valve open.

Cymric they say they have the whale system but yes the draining down basics are as you said .this is best letting someone that has the same system help

Thanks for your reply’s . I have now found the link to the correct handbook for my van which covers the whale system,drain the tanks and boiler then run the pump with the taps open until no more water comes out!