I have a coil in the diesel stove for heating
my hot water. Because the hot water tank is below and 30' away, I use a circulation pump. I also use a coil in a pellet stove that is used to heat my boiler for the hydronic system. It also uses a circulation pump for the same reason. In both cases I don't use a separate heat exchanger
. Just the water in the tank or the hydronic water.
If you're building a system from scratch, you need an expansion tank or an open reservoir. You will need a pressure relief valve near where the water exits the stove. Water turning to steam expands 16 times, meaning it makes pressure much faster than an air compressor
and an explosion can happen. It makes a big difference having your lines insulated.
If your radiators are above the stove, you can make a thermal circulation system. For example, the hot water exits from the top of the stove coil, rises to the radiator top and falls as it passes thru the radiator and looses heat. It returns to the bottom of the stove coil.
Boiler systems like I have and found in some houses run about 15psi of pressure. That allows a higher water temperature w/o turning to steam. 15 psi allows a water temperature of under 250° F.
This boat used baseboard radiators when I bought it. I changed over to marine
forced air heaters because I could heat a cold boat faster and at a lower water temperature. The radiators took 2+ hours to heat from cold. The forced air takes about 30 minutes
My boiler was set at 220°-240° and now is 160°-180°. The boiler is oil
fired, and if the pellet stove isn't on saves 1-2 gallons a day at the lower temperature.
If you always keep the temperature below 180° you can use hot water pvc pipe. If you don't have absolute temperature control or don't know your temperatures, use copper pipe.
I installed thermometers on both sides of both coils so I know my temps. Also valves so I can regulate the flow rate and shut down the coil in case of a leak.
The problem with the diesel stoves burning dirty is the new fuel
the EPA is shoving down our throats. It doesn't burn as well. Adding a catalyst ( like Archoil AR6200) helps the stove burn clean, engines start better in cold weather
, too. Also, a separate tank with #1 diesel or kerosene works.