Pin holes regularly occurring in pipes leading from calorifier

[Andy Bav]

2010 V42

Last year the cold water outlet from calorifier developed a pin hole causing a very fine mist that eventually filled the port “sub bilge”. Cut out the offending pice of pipe and sufficient left to reconnect... same thing happened about two days later. Tell tale vibration from pump every 10 minutes or so.

Same thing happens this year, only this time on the hot water outlet.... and then again last night on the cold water outlet, but the fine jet is hot water ?.

Pipe is about 2mm thick, and all holes have appeared within 20 - 100mm of calorifier outlet. Fading writing on the side looks like “whale”, and is original fit.

Very helpful berthholder has mended pipes for us and also pointed out that temp in calorifier is very hot, but trying to turn down temp is impossible as valve appears stuck. Could such high temps cause such tiny holes or has anyone got any other ideas ...

 

[Plum]

2010 V42

Last year the cold water outlet from calorifier developed a pin hole causing a very fine mist that eventually filled the port “sub bilge”. Cut out the offending pice of pipe and sufficient left to reconnect... same thing happened about two days later. Tell tale vibration from pump every 10 minutes or so.

Same thing happens this year, only this time on the hot water outlet.... and then again last night on the cold water outlet, but the fine jet is hot water ?.

Pipe is about 2mm thick, and all holes have appeared within 20 - 100mm of calorifier outlet. Fading writing on the side looks like “whale”, and is original fit.

Very helpful berthholder has mended pipes for us and also pointed out that temp in calorifier is very hot, but trying to turn down temp is impossible as valve appears stuck. Could such high temps cause such tiny holes or has anyone got any other ideas ...

Hi. Not sure what you mean by the cold water outlet. You should have 4 pipes/hoses: a cold water inlet, a hot water outlet and the other two connected to the engine cooling system. Anyway, best to replace all the hose, not just a section that is leaking. Use the correct specification hose and it will withstand the temperature. Do you have a 220v heating element too? When there are no leaks does everything work correctly, ie hot water from the hot tap and cold water from the cold tank?

Www.solocoastalsailing.co.uk

 

[VicS]

2010 V42

Last year the cold water outlet from calorifier developed a pin hole causing a very fine mist that eventually filled the port “sub bilge”. Cut out the offending pice of pipe and sufficient left to reconnect... same thing happened about two days later. Tell tale vibration from pump every 10 minutes or so.

Same thing happens this year, only this time on the hot water outlet.... and then again last night on the cold water outlet, but the fine jet is hot water ?.

Pipe is about 2mm thick, and all holes have appeared within 20 - 100mm of calorifier outlet. Fading writing on the side looks like “whale”, and is original fit.

Very helpful berthholder has mended pipes for us and also pointed out that temp in calorifier is very hot, but trying to turn down temp is impossible as valve appears stuck. Could such high temps cause such tiny holes or has anyone got any other ideas ...

What is the pipework. You say it appears to be marked "Whale" If it is Whale semi rigid pipework then the maximum recommended temperature for the hot water pipework is 65C. You say the temperature in the calorifier is "very hot", perhaps it is above this recommended limit.

You mention a valve but you do not say if this is a thermostatic control valve in the hot water feed from the engine, controlling the maximum temperature of the calorifier, or if it is a thermostatic mixing valve, fitted to a calorifier with an uncontrolled maximum temperature, to control the temperature of the hot water supplied to the taps and shower, Either way the temperature of the water at the taps and shower should be between 43C and 60C, ideally 46C to minimise the risk of scalding, particularly to vulnerable people.

You should either service or replace the valve which ever type it is if the hot water at the taps is above these recommended temperatures.

If you are talking about electrical heating of the calorifier then the heater should be thermostatically controlled and may need its thermostat adjusting or replaced

Aside from the H&S aspects, plastic fittings and semi rigid plastic pipework should not be closer to the calorifier than 14" . The connections then being made with metal or metal braided pipework. Maybe not complying with this recommendation is also part of your problem.

All the technical stuff is explained in more detail in the "Whale Technical Design Guide".
https://www.whalepumps.com/marine/s...ck_connect_technical_guide_specifications.pdf

 

[Momac]

Years ago we had a pinhole develop in a house plumbing pipe.
It was thought to be due to an impurity in the copper.
Are the new leaks I the original copper pipework?

 

[Andy Bav]

Thanks for very helpful replies

Electric thermostat was set to over 70, which based on responses is highly likely where the problem lays. Neighbour berth holder is a plumber by trade and will supply me with a list of replacement parts to bring out next visit, including the mixer valve on top of the calorifier. As a precaution I’ll close the engine heating circuit and rely on electric immersion heater.

In the meantime pipes have been replaced.

Thanks again for all replies.

 

[Plum]

Thanks for very helpful replies

Electric thermostat was set to over 70, which based on responses is highly likely where the problem lays. Neighbour berth holder is a plumber by trade and will supply me with a list of replacement parts to bring out next visit, including the mixer valve on top of the calorifier. As a precaution I’ll close the engine heating circuit and rely on electric immersion heater.

In the meantime pipes have been replaced.

Thanks again for all replies.

My calorifier has a fixed temperature thermostat fitted by the manufacturer and is set to 60C. (Higher than what normal house immersion heaters). My engine coolant, which runs through the calorifier, runs at 82C so the calorifier will probably be a little below that and engine heated water certainly feels hotter than the electricity heated water. My hoses that carry all the coolant hot water are rubber (automotive heater hose type) and the hot water outlet hose to the taps is plastic, all connected straight to the calorifier and all are 20 years old. The beauty of having high water temperature stored in the calorifier is you get a much greater volume of mixed hot water available out of your thermostatic mixer valve. With a lower temperature you will run out of hot water sooner. So, my view is, use hoses/pipes specified for the correct water temperature, leave the thermostat at a high temperature and adjust your thermostatic mixer valve to a safe outlet temperature.

Www.solocoastalsailing.co.uk

 

[volvopaul]

2010 V42

Last year the cold water outlet from calorifier developed a pin hole causing a very fine mist that eventually filled the port “sub bilge”. Cut out the offending pice of pipe and sufficient left to reconnect... same thing happened about two days later. Tell tale vibration from pump every 10 minutes or so.

Same thing happens this year, only this time on the hot water outlet.... and then again last night on the cold water outlet, but the fine jet is hot water ?.

Pipe is about 2mm thick, and all holes have appeared within 20 - 100mm of calorifier outlet. Fading writing on the side looks like “whale”, and is original fit.

Very helpful berthholder has mended pipes for us and also pointed out that temp in calorifier is very hot, but trying to turn down temp is impossible as valve appears stuck. Could such high temps cause such tiny holes or has anyone got any other ideas ...

If the heat is generated from shore power immersion then it’s the stat that’s either failed or you can adjust it under the plastic cover on the immersion .

The stat from the engine circuit is a radiator valve so it should be free to turn .

 

[Andy Bav]

Cheers Paul. That’s what we have done with the immersion heater... almost castrated myself in the process though :ambivalence: