September
2012 Page
6
PRODUCT DESCRIPTION
The Indoor/Outdoor Solid Fuel Boilers are designed to burn either seasoned, split cord wood or
coal. A water circulating pump moves the heated water to a heat exchanging device. This can be a base board
radiator, fi nned based board radiator, water to air exchanger, or existing boiler system; with the correct safety
apparatus installed to local codes.
The wood fi re combustion process is controlled by an aqua stat that senses exiting water temperature. The aqua
stat is set to the desired high temperature set point and will energize the solid fuel draft fan when the water
temperature drops 10 degrees below the high temperature set point. When the water reaches the high
temperature set point the aqua stat shuts off the electrical power to the solid fuel draft blower. It is not necessary
to connect a thermostat wire from the heating structure to the boiler. The boiler will sustain the desired
temperature water so that is available to the heated structure when needed. The operator uses the high
temperature setting and fuel load size to match the unit’s heat output with the heated structures needs. If heat is
not needed by the structure, full temperature water returning to the unit should put it into a damping cycle until
heat is taken by the structure or lost in the system through normal heat loss related to the eff ectiveness of the
system insulation.
A master switch should be incorporated such that all power to unit can be controlled. A fan switch or light switch
should be incorporated to allow manual shut off during fuel loading and fi re box maintenance.
A two position safety latch is installed on the fuel door and the ash pan door. Initial release of the latch should be
followed by a brief hesitation to allow ignition of unburned gases. Force from the unburned gases igniting can
cause the door to abruptly swing open to the 2nd position of the latch which stops further opening forcing the
ignition fl ame and gases to exit the fl ue instead of out the door.
These units should only be installed and operated as closed (pressurized) systems. An expansion tank is required to
provide safe changes in water volume related to system temperature change. A pressure relief valve is installed on
the unit to safely reduce system pressure if it ever exceeds 30 psi. The appliance is hydrostatically tested at the
factory to 60 psi.
The solid fuel boiler can deliver hot water to an existing gas, oil or electric boiler or can operate independently via a
bypass loop. Water must be continuously pumped through the appliance. The room thermostat cycles the exist-
ing boiler, starting the water pump. If the solid fuel boiler is out of wood, the primary boiler aquastat will signal the
primary fi ring system to take over and maintain system temperature.
An over temperature relief zone is required.
To signal a relief zone exchanger a surface aquastat can be used as a
safety limit control. If the water temperature passing through the pipe where the surfaces aquastat is mounted rises
above the set point (should be the same or slightly above the high temperature setting of the boiler when attached
to the hot supply line). This signal will over ride the normal setting for the exchanger and relieve the system of
excess heat. This reduces risk of over pressurizing the system.
