Fresh water Antifreeze

[rubberduck]

Boat is staying in most of this winter as we plan some winter boating if work ever calms down, hence have bought some fresh water system antifreeze. We use bottled water for drinking etc. Label says to isolate calorifier, anyone know why this is necessary ?

 

[Spi D]

Supposedly to save antifreeze.
You should drain the system completely, also the calorifier (mine has a valve for that). Then protect the system with the least possible amount of antifreeze blend.

Of course the engine coolant circuit will be protected by it's own antifreeze and need not to be drained.

BTW I used Winterban a couple of years back. It took several fill/empty cycles to get the smell and taste out of the system at next season start and I never used it since .

 

[Piers]

I just drain the system, install the tube heaters and de-humidifiers, and leave it at that. Never had a problem in the 11 years we've had Play d'eau.

Piers

 

[Spi D]

I just drain the system, install the tube heaters and de-humidifiers, and leave it at that. Never had a problem in the 11 years we've had Play d'eau.

Piers

Have you calculated the cost of using these devices? Depending on outside temperature I'd fear the number of running hours.

 

[Piers]

Have you calculated the cost of using these devices? Depending on outside temperature I'd fear the number of running hours.

True they are on the high side, but the benefits are not having to antifreeze anything more than the engines, no mould, and a sweet smelling boat. In my book it's worth it.

I forgot to say that after draining the freshwater system ready for winter, I use Milton fluid at the start of the season to disinfect the tanks and pipework.

This applies to the last 11 years. But now we are liveaboard in Guernsey it'll be a whole new ballgame which we'll have to work out as we go. For example, we installed one of our de-humidifiers yesterday, emptied it before we went to bed, and it was full by the time I went for my early morning pee!

 

[A_8]

Agree that there is no need to put antifreeze in the freshwater system, I'm in a colder environment then you and keep the boat on the hard oktober-march. We sometimes get down to -20 degrees c. I just empty the tank, drain the calorifier, let the pump run dry for awhile and make sure the water is drained from the taps and shower outlets and let the taps stay in their open position.
Maybe not needed in some parts of the UK or relevant if the boat is in the water with a bit of heat but don't forget your bligde pumps and other pumps as well as the toilet.
Also agree on the dehumidifier and a bit of heat, it makes a big difference to the climate in the boat.
Another suggestion is making sure the engine room is damp free, I found that the temp changes sometimes creates condensation on the surfaces of the engines which makes them rust. A blanket covering the engines helps but a second dehumidifier and heater is even better.

 

[superheat6k]

Generally in Southern UK climes, the seawater stays quite a few degrees above freezing, so the lower wet portion of the boat stays nicely above freezing, so there is only the top half to worry about, whereas out of the water the whole boat cools down, and therefore is more at risk during freezing weather.

I leave a small oil filled rad in the engine bay that will kick in at around 2-3c. If a real cold snap arrives then I will put the immersion on set to its lowest setting, along with further oil filled rads in the cabin.

Last year my Winter electricity cost about £50. I do have the advantage that I live close to the boat so I can easily call by to switch things on or off as the weather changes.

 

[oldgit]

B1 of the Thames forum keeps his Hardy 26 in a marina on the Thames.The boat was located in a section of the marina where the water did freeze and a layer of ice could be seen on the surface of the water.
He was interested to find out the actually facts regards winter temperature inside boats and the need for heaters and dehumidifiers.
Installed a cheap little USB device which recorded the temperature both in the wheelbox and in the bilge every 30 mins or so over a certain period,think it was 4 weeks.
This could be download into your laptop and a graph displayed.
Despite record prelonged cold periods and the fact that the water froze in the marina several times , the lowest section of the bilges did not go below 0 C at any point.
If the boat remains in the water and is not on the hard,conditions do not appear to be quite as severe as feared during " normal" winters.

 

[Vara]

My boat in the water at Dover, with no heating on, the temp in the bilge/engine space did not go below 5° throughout last winter, well not according to my max/min thermometer. Min air temp during that time was -5°.

Most of my domestic water is on or below the waterline so it reflects sea, rather than air temp, maybe different for a mobo with less in the water.