Keystoker Coal Boiler Domestic Hotwater Quick Question/

My neighbor is in the process of hooking up a used Keystoker Coal Fired Hot Water Boiler. He got the thing working after doing a bunch of research on this site. My question is this, when filling the supply and return lines with water should water come out of the domestic coil? While we were filling the lines water started coming out of the domestic coil supply and return. He currently does not have the domestic coil plumbed we just installed valves and turned them off.

Is that normal or is his coil shot?

No, it shouldn't. The domestic coil is just that....a coil inside the boiler water cavity. If he wants to use the domestic coil he's going to need to install a new one. If not, I suggest pulling the leaky one out and cap of the boiler.

If he has both the input and output capped will it do any harm to just leave it that way?

No, you can leave it capped off and it should be fine.

Thanks for the information, maybe he can source another coil for it.

It wouldn't hurt to pull the coil out and take a look at it, maybe it froze and burst and can be soldered up.

I have no experience with boiler coils, but LOTS of experience with fixing frozen copper.

If time permits, it would be fun to pull the coil and inspect it.
It can probably be repaired if it is not corroded. Make sure you have a new gasket or gasket material and/or Permatex.

he can probably get a replacement, gaskets, etc fro keystoker