Beckett CF2500 Manuale Utente

CF2500/CF3500 Burner Manual

When fi ring over 20 GPH the CF2500 and CF3500A will 
be supplied with a fl ame safeguard control. An airfl ow 
switch and low-fi re start relay will also be supplied. 
Consult local, state, and federal codes for burner 
requirements above 20GPH. 

Install the burner and all wiring in accordance with the 
National Electrical Code and all applicable local codes or 
requirements.

Wire the burner in compliance with all instructions 
provided by the appliance manufacturer. Verify operation 
of all controls in accordance with the appliance 
manufacturer’s guidelines.

Initiate - Power is supplied to the control.  The 
control performs a self-check to ensure proper 
operation.
Standby - the burner is idle waiting for a call for 
heat.  When the call for heat is initiated, the burner 
will proceed to step 3.
Pre-purge - the burner will begin a 60 second pre-
purge to clear the combustion chamber.  The burner 
checks the air fl ow interlock to see if air is being 
provided.  If the air fl ow is not present the burner 
will lockout if jumper JR3 is cut or recycle if the 
jumper is intact.
Trial for Ignition - The RM7897A has two trial 
periods.  The fi rst is for light off the second is for 
main fl ame establishing.  The burner must see 
fl ame within 10 seconds if jumper 1 is intact or 4 
seconds if jumper 1 is clipped.  If the fl ame is not 
established, the burner will lockout if  jumper 2 is 
clipped or recycle if the jumper is intact.  The burner 
will then proceed to main fl ame establishing.  If 
fl ame is not sensed within 3 seconds the burner 
will lockout or recycle depending on the status of 
jumper 2.
Run: With a fl ame established and the control 
continuing  to detect a fl ame, the burner will operate 
in the RUN mode until the load demand is satisfi ed 
or a limit opens.

If terminals RC1 and RC2 are jumpered, the 
burner operates in the Low-High-Off Mode. 
The burner starts at Low, goes to High after the 
fl ame stabilization period. Flame is extinguished 
when the load is satisfi ed or a limit opens, and 
the burner is sent to post purge. 

a.

If a high/low control has been wired between 
terminals RC1 and RC2 the burner starts at 
Low and is released to go High after the fl ame 
stabilization period. It can repeatedly cycle 
between low and high as necessary to meet 
load demand until the load is satisfi ed or a limit 
opens. The  burner is then sent to post purge. 

Post purge - The control enters a post purge cycle 
to clear the combustion chamber of gases.  Length 
of the post purge is factory programmed at 15 
seconds.

b.