Emptying domestic water system for the winter

[Storyline]

I have a calorifier/immersion heater tank and a separate small accumulator pressure tank. The calorifier has a knob on the top which clicks and the accumulator has a small drain plug at the bottom. These supply three sinks (galley & heads x 2).

I emptied the main water tank by just leaving one of the taps on until it ran dry but what is the best procedure to ensure as much water as possible is removed from the system (particularly the califorier & accumulator) ?

Many thanks

 

[Trundlebug]

Easy bit first, the accumulator.

As long as you've released all the pressure out of the system (turn on the taps, and leave them on with the pump off) then that's as much as you can, and need to do for the accumulator. It does help to have a drain point at the lowest point in the system so you can drain the pipes too. Disconnect if there isn't a drain point.

The Calorifier. You do need to get some of (but not all) the water out of it to allow for expansion should the contents freeze.
If your PRV is on top of the calorifier, you can't use that easily.
Do any of the pipes (not on the coil / heating circuit) enter half way up or at the bottom? If so, disconnect one, or as above disconnect at the lowest point elsewhere and allow it to drain down. For push fit plastic pipes it's easy; alternatively unscrew any screwed fittings.

If all the pipes go in at the top (unlikely) you'll have to blow out some of the water by blowing or pumping air at low pressure (max 5psi) into the inlet pipe, and allowing the water to come out through the taps.

 

[vyv_cox]

There is usually a drain tap on a calorifier as it is not possible to empty them using the pump. If yours is the exception removing the cold water inlet hose should do it, as this will normally be at the lowest point.

 

[maby]

http://www.marinemegastore.com/product-product-AFX_9_90760.htm

but do flush well after use - I didn't realise that it was still in our boat following delivery and my first cup of tea on board tasted terrible!

 

[Billjratt]

Don't forget to drain any filters there may be in the system.

 

[ghostlymoron]

Don't forget to leave taps open and remove shower heads.

 

[maxi77]

The same problem affect the cravan community and here is their solution.

http://www.keepfloeing.com/products.html

 

[ghostlymoron]

The same problem affect the cravan community and here is their solution.

http://www.keepfloeing.com/products.html

Not really the same system. Caravans don't generally have calorifiers.

 

[pvb]

My boat stays afloat in a marina all year round, and I never drain the freshwater system. If the forecast is for several days of freezing conditions, I leave the taps open in the galley and heads, otherwise no special precautions. Never had a problem. However, if I were to take the boat out of the water over winter, I'd certainly drain the calorifier.

 

[nigelmercier]

http://www.marinemegastore.com/product-product-AFX_9_90760.htm

Assuming you want it for the winter next year.

 

[jwilson]

If you have a transom shower fitting take off the head - they crack if frozen. This is the most vulnerable point on board to early frosts. Mine was difficult to source a replacement and horribly expensive.

 

[Steve_N]

what is the best procedure to ensure as much water as possible is removed from the system (particularly the califorier & accumulator) ?

Many thanks

I empty my calorifer, down to the level of the cold water input at the bottom of the cylinder, by back-pumping it using the fresh water pump.
Swap the outlet hose/connection at the water pump over onto the inlet side.
Put a hose on the now-vacant pump outlet and direct it into the sink or overboard.
Open the hot taps and turn on the pump and the calorifier is pumped dry.

 

[ghostlymoron]

If you have a transom shower fitting take off the head - they crack if frozen. This is the most vulnerable point on board to early frosts. Mine was difficult to source a replacement and horribly expensive.

See post #6

 

[vyv_cox]

Not really the same system. Caravans don't generally have calorifiers.

They do have a water heater though, containing a tank. All of my vans have had Truma ones, which have a thermally operated solenoid drain valve that opens at +4C. Can be a real nuisance that many owners over-ride using a clothes peg to prevent the valve from opening.

 

[maxi77]

How do you think we get hot water? Although they don't have a connection to the engine cooling system most have a gas fired boiler with an immersion tank, v expensive if you freeze them. Some have a frost dump valve that works at about 4 degrees

 

[Border Terrier]

Divn't forget ya bilges pet