Alde 3010 Boiler Corrosion

[Richman47]

Has anyone else had to replace their Alde 3010 Boiler due to corrosion and leakage of anti-freeze at the connection to the tank. We recently needed to replace our entire boiler with the 3020 model at a cost of $4900. It appears to me (see attached photo) to be a manufacturing defect. Connecting different metals causes galvanic corrosion. The metals used here don't appear to be identical.
I asked Alde about what they've done to correct this problem and was told they changed the antifreeze formula to better inhibit corrosion.
Doesn't seen like a good fix to me.
If you've had a similar problem I'd like to know what Alde (Truma now) has done for you.

 

[GeorgeRad]

Ouch, that is expensive fix for what it looks like manufacturing mistake. Alde folks welded plated/coated steel pipe to stainless steel tank, it will corrode in water or coolant, coolant is an electrolyte. Is this pipe for heated water or for ethylene/propylene glycol? - see the diagram. https://www.motorhomevoyager.co.uk/know-how/alde/alde-compact-3010-boiler/

 

[Richman47]

I hadn't seen that diagram before. It appears that its the hot water pipe.
I too thought they shouldn't have used a plated pipe from the tank.
Have you had this issue too?

 

[GeorgeRad]

No, I have my own heating system composed of Espar (Eberspacher) Hydronic D5 + Isotemp marine heater for water heating and Espar Airtronics D2 for space heating. My system was about $2,500 in 2013/14.

I would check if the new boiler has a steel or a SS pipe, you could try a magnet pull test on the boiler body and the pipe, some stainless steels are not magnetic.

If this is a steel pipe electrolytic corrosion is just a matter of time. I think you have these potential options:

1. Get the story straight from Alde/Truma. What is different, is it all stainless steel. Different coolant is a questionable answer. Was it R&D or manufacturing error?

2. There must be input and output pipes from the hot water tank, did both have corrosion, are both the same material?

Let’s hope that the new boiler is all stainless steel.

 

[Richman47]

Thanks George.
I'll get back in touch with Alde. Problem is talking to a knowledgeable person.
Rich