4
DO NOT INSTALL GATE VALVES ANYWHERE IN THE SYSTEM. IF THERE ARE GATE VALVES,
AND THEY ARE LEFT CLOSED, IT WILL CAUSE DAMAGE TO THE SYSTEM AND COULD POSE A
SERIOUS SAFETY RISK.
All pipes should slope downwards slightly towards the water jacket to prevent air from being trapped in the
line.
Pumped / Active System
If your storage tank is located below the stove or a great distance from the stove, you will need to use the
pumped / active system. With this system, an electric pump is used to circulate the water and a heat activated
sensor is used to activate the pump when the stove is hot.
Caution: In the event of a power failure,
water may stop moving and become
highly pressurized in the water jacket and
piping. An additional pressure temperature
relief valve (PTV) must be located in the
hot water line within two feet of the water
jacket. The PTV must be installed
according to local building and safety
codes, and must be piped to a drain.
NOTE / DANGER: If you plan to use your
water jacket during a power outage, you
MUST have a source of cold water to
replace any hot water you draw off for use.
Failure to do so can cause an air lock at
the top of the system. This will prevent
thermosyphon circulation and could result
in excessive pressure and explosion.
DO NOT INSTALL GATE VALVES
ANYWHERE IN THE SYSTEM. IF THERE ARE GATE VALVES, AND THEY ARE LEFT CLOSED, IT
WILL CAUSE DAMAGE TO THE SYSTEM AND COULD POSE A SERIOUS SAFETY RISK.
Installation
It may be difficult to find all of the fittings required at your local plumbing or hardware store. If you require
parts that you are unable to find, you can order them through:
Lehman Hardware
One Lehman Circle, P.O. Box 270
Kidron, Ohio 44636
888-438-5346
www.lehmans.com
NOTE: Any time the installer is connecting different metals to each other (i.e. stainless steel to steel, steel to
copper, etc.), they must use a brass nipple*. If this method is not used, electrolysis between the different metals
will cause the pipe to break down and leak. Use steel or brass pipe and fittings on any line within three feet of
the water jacket. Do not use copper fittings within three feet of the stove – in the event water flow stops, heat
will rapidly build up in the pipe and melt soldered joints, causing leakage and potential safety hazards.
* Some local building codes require dielectric unions rather than brass nipples. Although brass nipples are a
better alternative (the plastic gasket in dielectric unions can melt at extreme temperatures), you must comply
with local building codes.