EKO 40 cooling pipe, can I use it as a DWH preheater?

Just wondering how this weird "coolant pipe" running across the top of my EKO 40 could be used to its maximum benefit? Could it be used as a preheater HX for my DHW, I suppose it would also cool the boiler in an emergency if I had a circulation pump rigged to run in an outage (probably its purpose)? I have no idea how it is coupled with the boiler internals and the manual says to just leave it alone and cap it off so it can still vent. Has anyone here used it for something?

Thanks to everyone on this board, for making it what it is!

I forgot to mention that I'm skating by this year without storage, once that is in place things will run off of that. so I'm trying to capture all the possibilities that this eko 40 can give me at the moment. Thanks again for any info about the "cooling pipe"

The coolant pipe is meant to be used as a means of overheat protection, and from what I have heard is a European requirement. The idea is that there is a valve connected to your cold water supply, and if the boiler is going to overheat, it opens and pushes cold domestic water through it. This water then just gets dumped to a drain.

Not sure if the coil itself is rated for potable water use, so that would be the first thing to check on. Also, I dont know if having the cold water like that running through your boiler would be a bad thing as far as any condensation is concerned (dont know where its positioned).

Its not a bad idea, just something that you would want to dig into more first. Someone else here may have better insight.

Is it copper? If so, I don't think anything bad would happen, and just might be a good idea. Almost a tankless coil. I wouldn't try putting all my flow through it though, unless yours is bigger than mine - it's pretty small so might restrict it some. Maybe divert half the flow through for preheat? I also don't know the internal construction - but would imagine it is a lot smaller (therefore would not transfer near as much heat) than a typical tankless coil.

Good points on the potable usage, it appears to be iron pipe so its probably not a wise decision to use it after all, I guess it would add some rust is all, but perhaps the sealants they used weren't for potable either?