Calorifier Problems

[dgod3]

As soon as a tap is turned on water seems also to be being pumped into my engine system as the header tank overfows and water flows into the bilges. I have not checked the hot tap but this certainly happens with the cold as soon as the pump runs. Recently the saildrive seal was replaced and I wonder if the fitter reconnected the 2 hoses from the engine to the calorifier the wrong way round? Would this make any difference? Any clues please?

 

[sarabande]

or a wrong connection in the pressurised circuit, leading INTO the output / onput from the engine.

Unless the calorifier coil is leaking (another possibility), there should be no way that the pressurised freshwater side could interact with the engine side.

Check here
http://www.jabscoshop.com/article.asp?ls...esh+Water+Pumps
and click on the diagram.

 

[Bav34]

My calorifier has conventional blue and red pipes with white connectors. These feed water from the main water tank into the calorifier and out to either the hot or cold taps.

There is absolutely no link between them and the engine.

The engine has two black pipes that circulate the 'fresh' water in the engine (anti-freezed actually) into and out of the coil that sits inside the calorifier. This is how the heat gets into the calorifier.

Assume you know all that but as you don't give engine/boat details I'm perhaps stating the obvious.

The ONLY way that the water in the calorifier could get into the engine given the above set up would be if the coil inside the calorifier was perished as stated above.

However if that has happened you would also have ENGINE water in the calorifier .... coming out of the taps!

Hmmm. /forums/images/graemlins/confused.gif

 

[Danny]

Connecting the two coolant circuit hoses the wrong way round wouldn't have this effect but switching one coolant connection with one domestic connection might. This could effectively combine the two systems and the fresh water pump would pump water from the water tank, through the cal heat exchanger and the engine f/w cooling circuit, back through the cal tank and then out the taps! Seems unlikely he would have done this though.

If not that then suspect the heat exchanger coil is leaking. Fresh water would be forced from the domestic circuit into the coolant circuit until the pressure equalised. When you open a tap the pressure in the domestic side drops and the pump starts. The pressure builds until the pump cuts off and more leakage occurs until the pressures equalise again.

If you have service valves on the coolant pipes to the calorifier then turn them off, disconnect one of the pipes from the calorifier, and see if fresh water is pumped out. If so you'll need a new calorifier.

 

[Mrnotming]

Hi Delwarrior & all! Can be most vexing when it is all wrong!
I would begin at the calorifier with disconnecting everything and blowing through the coil with the other end stopped off with a suitable bung. if no leak( maybe use the dinghy pump to work up a little more pressure? Then mark clearly the two connections tested. Then test the other two by the same method. Some boats calorifiers have a non return valve near the inlet an din one instance this could be reversed causing no hot at the taps.Not your problem though. If calorifier is ok and there are no crossed connections, then the only other thing I can think of is a loose rubber end cap or both loose on the end of the heat exchanger. Check all circlips. This did happen to me once and the header tank overflowed. Best of luck