Main Nymph - gas hot water boiler

[Big John]

This is a very long shot but hoping some one out there may have an answer. Friend of mine did not fully drain the gas water heater- Main Nymph- and he has just got around to recomissioning after the winter lay-up and found that the heat exchanger has cracked due to water left in the exchanger and frozen causing a crack. The model and part are long gone obsolete but there may be some one out there that has removed one of these to upgrade to a newer heater and it is still in the junk heap in the back of the workshop. Any help with this would be helpful. Thank you.

 

[wingcommander]

Popular on camping van installs . So maybe worth a look

 

[galeus]

I don't know that particular gas boiler, but I have soldered sucessfully a Paloma heater some time ago with a similar problem.

 

[Big John]

For anyone interested. After investigating various options (replacing with a new hot water unit would have required major alterations to the location of the heater and roof alterations to be able to be covered by BSS) and no engineering company willing to even look at the problem we decided to tackle the problem.

After locating the leak in the exchanger the "fins" were folded back to expose the split in the copper. The copper was cleaned and roughed up.

A piece of copper pipe was cut, flattened and shaped to fit. Also a small strip of SS mesh was cut to suit. As the exposed split would be permanently exposed to water I used JB Weld Marine which is totally water proof after it has set. This was applied to the mesh (the mesh stopped the epoxy dropping through the split) and the copper plate was then placed over the mesh. A good amount of the JB Weld was used.

This was fully set after 24hrs. JB Weld Marine has high strength but low heat tolerance in this application.

To be able to withstand the flames from the burners I then applied QuickSteel. This took about 5 hours to harden then poured boiling water into the heat exchanger via the water tube and allowed to cool. To be sure of good flame tolerance I applied a second coat and did the boiling water again. ( Instructions for the QuickSteel recommended the item being repaired to be heated to ensure the proper curing)

The "fins" were folded back as best as I could.

Heat exchanger refitted and I am pleased to report the Main Nymph is not fully functioning and no leaks.

As galeus suggested it could have been soldered but I did not have the equipment to carry out the soldering.

 

[galeus]

You've done very well, it looks very tricky

 

[Big John]

Thanks galeus. It was iether that or a whole new setup with flue mounted in the roof plus the expense of a new heater and remedial work required. Also useing a Gas Safe engineer to be sure of H&S and BSS.

 

[Big John]

For anyone interested. After investigating various options (replacing with a new hot water unit would have required major alterations to the location of the heater and roof alterations to be able to be covered by BSS) and no engineering company willing to even look at the problem we decided to tackle the problem.

After locating the leak in the exchanger the "fins" were folded back to expose the split in the copper. The copper was cleaned and roughed up.

A piece of copper pipe was cut, flattened and shaped to fit. Also a small strip of SS mesh was cut to suit. As the exposed split would be permanently exposed to water I used JB Weld Marine which is totally water proof after it has set. This was applied to the mesh (the mesh stopped the epoxy dropping through the split) and the copper plate was then placed over the mesh. A good amount of the JB Weld was used.

This was fully set after 24hrs. JB Weld Marine has high strength but low heat tolerance in this application.

To be able to withstand the flames from the burners I then applied QuickSteel. This took about 5 hours to harden then poured boiling water into the heat exchanger via the water tube and allowed to cool. To be sure of good flame tolerance I applied a second coat and did the boiling water again. ( Instructions for the QuickSteel recommended the item being repaired to be heated to ensure the proper curing)

The "fins" were folded back as best as I could.

Heat exchanger refitted and I am pleased to report the Main Nymph is not fully functioning and no leaks.

As galeus suggested it could have been soldered but I did not have the equipment to carry out the soldering.


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Just noticed a typo error. Heat exchanger refitted and I am pleased to report the Main Nymph is now fully functioning and no leaks.