Tony-B...
Posted: Sun Nov 01, 2009 7:09pm
Post Subject:
Winterisation
Dear Duncan, in short NO. Unless special provision has been made to do this during construction it is highly unlikely that you can totally drain the domestic water system. There will always be low points, possibly under the floor where water will remain. On modern boats with plastic plumbing this is not such a problem because the plastic usually gives enough when the water freezes and many boaters never drain their system down. I must say that last winter I was getting a bit concerned but the boat was fine with a full system. You will find that much of the plumbing is below the waterline so heat from the surrounding water helps to prevent the plumbing freezing. It is VITAL to drain the diaphragm chamber on instant gas water heaters and it would be a good idea to drain or remove an expensive shower mixer valve. You should also leave all the taps open and the water tank less than full so there is space for ice to expand. If you want to drain down the system (as far s it will)pump as much water as will come out of the taps etc. whilst running the engine to ensure the batteries are not discharged. Remove the hot water outlet and the cold water inlet from the calorifier and drain that down. Follow any instructions for the toilet. Drain any instant gas water heater, the shower mixer and domestic water pump. Mix a 50% antifreeze mixture in a bucket, get someone to hold a bucket under the shower outlet, operate the shower pump whilst pouring the mixture into the shower waste until coloured water comes from the waste. Dispose of the antifreeze mixture responsibly. Remove the filter bowl from any water filters. However in most years you stand a very good chance of not having to do it. Tony Brooks