Making a External DHW Coil

 
User avatar
oliver power
Member
Posts: 2970
Joined: Sun. Apr. 16, 2006 9:28 am
Location: Near Dansville, NY
Stoker Coal Boiler: KEYSTOKER Kaa-2
Hand Fed Coal Stove: Hitzer 50-93 & 30-95, Vigilant (pre-2310), D.S. 1600 Circulator, Hitzer 254

Post by oliver power » Sun. Mar. 15, 2015 9:24 pm

I've known many people to have external copper tubing attached to there stoves for heating hot water. My uncle fabricated a series of back & forth horizontal runs of 3/4 inch hard copper tubing up the side of his stove. Looked nice & neat. The copper was not covered. The tank set within 5 or 6 feet away. Water circulated without a pump. Worked good for quite some time. May have worked better yet if copper was covered.


 
User avatar
dave brode
Member
Posts: 478
Joined: Fri. Jan. 15, 2010 5:47 pm
Location: Frostburg, Maryland [western]
Stoker Coal Boiler: Keystoker KAA-2
Hand Fed Coal Boiler: used to have a 5 section Red Square
Coal Size/Type: rice anthracite

Post by dave brode » Sun. Mar. 15, 2015 11:23 pm

Fwiw,

I had a homemade setup INSIDE the firebox on an old hand fired bit coal boiler. I see no difference in doing something inside the firebox on a stove or furnace.

The boiler's rear section had two holes, high in the fire box, one above the other. I ran 3/4" copper into the holes. On each, I had a flat tee, short pipe, another tee , another short pipe and an ell. Confusing, but picture 4 risers, apx 6" high. I fashioned a 14ga s/s heat shield to keep the fire off of the pipes. The ells were the kind with the brackets that can be fastened to the wall etc. I riveted the heat shield on using those. It was in there for some years w/o issue. It flowed via gravity through sloped piping to/from tees in the top/bottom of the DHW tank. It kept the domestic water HOT! So hot that the relief valve would occasionally spit. Even so, the normal soldered copper stayed in there.

I later installed an iron fireman stoker. I had to move things around to get the stoker in the room, and failed to hook the lines back to the tank. One fire with no water in the pipes, and the solder joints failed, and it fell apart.

Dave

Post Reply

Return to “Coal Bins, Chimneys, CO Detectors & Thermostats”