NTI WF200 Installation And Operation Manual page 11

WF200
WF200 Installed as an Add-on to an Oil Boiler
The WF200 is factory supplied with controls necessary for a typical installation as an add-on to oil boiler. In
addition to the preceding General Field Wiring and the General Boiler System Plumbing instructions, use the
follow instructions to complete the plumbing and wiring for a WF200 installed as an add-on to an oil boiler.
Figure 5-1 WF200 Installed as an Add-on to an Oil Boiler – Plumbing Arrangement
Existing Oil Boiler
A
B WF200 Wood Boiler
C Existing Heating Circulator
Wood Boiler Circulator
D
E Isolation Valves
Expansion tank
F
G Zone Valves (N.C.)
H Dump Zone Valve (N.O.)
I Existing Fill/Backflow Valve
Pressure Relief valve
J
K L4006B Aquastat
L4081A Aquastat
L
M Damper Motor
N Existing Boiler Aquastat
O Flow Check Valve
P Swing Check Valve
Q Water Supply
R Existing system Return
Existing Boiler Supply
S
Supply to Zones
T
Additional Wiring Guidelines for Oil Add-ons:
 Power both boilers from a single electrical circuit.
 Wire the system in accordance with Figure 5-2 – deviating from this could negate important safety
shutdown mechanisms – possibly leading to a "runaway boiler".
 Enclosures of control devices are not to be used as junction boxes to extend supply circuits from one
boiler to the other.
 Upon completion of the installation, adjustments of any controls, other than the room thermostats, should
not be required when changing from one fuel to the other.
Installation and Operation Manual
11