INSTALLATION AND OPERATION INSTRUCTIONS
4-4
DC SERIES BOILERS / WATER HEATERS
DC 15-95, DC 15-96, DC 20-125, DC 33-160
4.1.15 Fan and gas valve removal instructions
1.
Turn off the power and the gas supply to the boiler / water heater.
2.
Remove the front cover and allow the boiler / water heater to cool down.
3.
Disconnect the 2 electrical plugs attached to the fan.
4.
Loosen the union nut at the top of the gas valve. Carefully remove the Orifice
and O-ring and keep in a safe place for re-installation later. Ensure you
protect the gas valve outlet from dust and debris.
5.
Remove the 2 hex nuts connecting the fan to the burner housing and carefully
remove the fan. You will find a gasket attached to the fan outlet as well as a
back flow valve above it, inserted in the heat exchanger. Keep these items in
a safe place for re-installation.
6.
If the removed fan is to be re-installed, ensure the fan and venturi are clean
and dust free.
4.1.16 Fan and gas valve re-assembly instructions
1.
If the fan is being replaced, move the venturi to the new fan. Note that the fit
is tight.
2.
Place the fan gasket on the outlet of the fan housing. The gasket has 2
locator pins to ensure the gasket does not move during installation.
3.
Attach the fan to the burner housing and install the 2 hex nuts. Tighten the 2
hex nuts with a wrench.
4.
Insert the Orifice and O-ring between the gas valve outlet and the gas line to
the fan. Tighten the gas valve union nut with a wrench. Ensure the gas valve
inlet (lower) nut is tight.
5.
Connect the 2 electrical plugs to the fan
6.
Restore gas supply to the boiler / water heater and test the gas valve inlet for
gas leaks.
7.
Restore power to the boiler / water heater and create a call for heat or hot
water.
8.
Check for leaks at the gas valve outlet and the connection between the fan
and the burner housing.
9.
Install the cover to the boiler / water heater.
10.
Reset the boiler / water heater to normal operation.
Figure 39
DANGER
When servicing or replacing
the fan the following parts
must be moved from the old
fan to the new fan.
•
Venturi
•
Back Flow Valve
Failure to relocate these parts
to the new fan may cause
an immediately hazardous
situation which must be
avoided in order to prevent
serious injury or death.