Harman SF250 Coal Stove Installation & Operating Manual page 12

Example 2: Circulating pump method. Used when the distance is more than ten feet or when the stove is on a higher level
than the existing water heater. In addition to a circulator, you may want to add a aquastat to control the pump according to
water temperature. This is not necessary if the circulator is left run continuously. Another option is a gate valve placed near
the circulator to control the rate of flow.
1. Turn off the water heater and the water supply to it. Drain the tank completely.
2. Remove the Temp/Pressure relief valve and discard. Install a short ¾" nipple and tee (1) along with a new Temp/Pressure
relief valve.
3. Remove the drain valve, at the bottom of the storage tank. Install a ¾" nipple and tee, and reinstall the drain valve to the
tee (4).
4. Install a circulating pump (6) as shown. Run ¾" copper tubing from the circulator to the lower leg of the coil. This is where
the optional gate valve (5) can be installed.
5. Install a ¾" tee and a 150 lb. pressure relief valve (7) in the top leg within 2 feet of the top outlet of the water coil.
6. Complete the copper line by running it back to the tee at the top of the water tank, making sure to install a vent elbow
and automatic air vent (2) at the high point of the line. The optional aquastat can be installed in this line a maximum of
six feet from the stove. The aquastat must be a "close on temperature rise" type and must be wired and set to turn on the
circulator when the water temperature reaches 120˚ Farenheit.
The system is now ready to be refilled and power restored to the water heater ONLY after the tank is filled.
EXAmPlE 2: Circulator method.
(more than 10 feet.)
12
wATEr COIl OPTION
3-90-70738R9_08/13