Draining fresh water system

Stellina

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I have a hot/cold pressure system for the first time on my new-to-me boat which I need to drain for the winter. I emptied the tanks by running the system but would this leave enough water in the pump/expansion tank or pipes to cause damage when it freezes? What is the normal way to empty the sytem and make sure the pump is safe.

Andy
 
due to your cold winters i think i would remove a few pipes to ensure the system is clear of water.
i always ensure the expansion tank / accumilator is empty each time i leave the boat by turning off the power & open a tap thus draining the tank & removing pressure from the diaphram in the tank this also gives the diaphram a greater life expectancy
 
Find the water pump then disconnect both inlet and outlet hoses and allow to drain. The inlet will probably be fitted with a gauze filter and it's a chance to give this a clean. Leave disconnected until refitting next season.

If you have a calorifier, make sure that this is also drained using the pressure release valve and not just by running the water taps dry.

If you have plastic Whale type tap outlets, remove these or they may split in a frost.

Hope this helps.

Dave
 
With your location the boat is best stored in a heated shed for the winter. If not, all pipes and calorifier should be drained down completely (disconnect and blow them out), run 50% antifreeze mixture through the engine seawater cooling system and make sure the diesel in the tank, pipes and filters is specified not to go waxy in the temperatures which will be experienced. Also make sure the antifreeze mixture in the engine cooling system is of a concentration suitable for the likely low tempertures.
 
always remember my father telling me it is not the pipes freezing that splits pipes its when they start to rapid thaw - as ice expands as it thaws.
i have also been told if you have frozen pipes open the couplings to allow for expansion of ice

sorry for lecture
 
where a water system can't easily be fully drained out, is there some sort of non poisonous antifreeze that can be used? Eg alcohol?
 
Some years ago I had to drain down a water system and after pumping most of the water out with the electric pump I was left with the water in the hot tank and pipe work.
So what I did was to use my compressor - after disconnecting the water outlet from the main tank I pressurised the line and undid the hot tap - to my surprise it worked like a charm.

Peter.
 
drain fresh water tank,drain calorifier by taking off bottom connection open pressure relief,by turning red knob at top 90deg.this enables cal. to be drained easier.Remove fresh water pump,as there is always some water left in (I take home)open cold taps one at a time and blow down with your "gob", no mean feat ,till you hear air bubble out,then do hot taps one at a time.If you have a shower mixer its best to drain this ,if you can remove all the better.remove toilet inlet pipe and suck up a 33% A/F mix,then pour rest in bowl and pump thro.Its no good just pouring in the bowl as you will still have water in the vavle arrangement where the C/O lever is.Switch off immersion heater, this should be done FIRST!!!.
 
put a hose on the calorifier valve and ,after taking one of the drain tubes off a through hull connector (sink drain?) take the tube under boat and then open calorifier drain .It may need a suck on the tube to get the water flowing,and the taps must be open.
 
Having emptied the water tank I then complete the draining of my system, including the calorifier, by moving the pressure pump outlet pipe to the inlet side and then running a hose into the sink from the pump outlet. Open the taps (one at a time works best) and run the pump to completely empty the system, pipework and calorifier included.
 
Thanks for the tips; I will disconnect the pump (might even take it home) and try blowing out the rest. That leaves the water heater so I will re-read the manual and look at draining it.
 
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