IBC Technologies Inc.
20
VFC 15-150 and VFC 45-225
add a 9” pigtail to bring 120v to the
bottom pair of contacts on the Pump/
Zone Valve Terminal Block located on
the upper right-hand edge of the
controller. The upper 3 pairs of contacts
on this green connector strip are then
powered to manage up to 3 load pumps –
the top pair for Load 1, the second pair
for #2 etc. Once the controller is
programmed for the respective loads, the
boiler will manage all the loads without
need of further relays (OK for loads up
to 1/3 HP; for more – use a protective
relay). The green Pump/Valve terminal
strip is not pre-wired because some
installations will use it to manage 24 v
zone valves. .
The primary pump is connected to the
White/Yellow pair labeled
Primary
Pump
. This lead is factory wired to the
controller (and its 120 V
AC
supply) at
the upper right backside of the controller
board – do not attempt to connect the
primary pump to the Pump/Zone Valve
Terminal Block along the controller’s
right edge - this is for the secondary
pumps and/or zone valves only. Connect
the pump's Black wire to the Yellow of
this pair (switched Hot). The White/
Yellow pair should be individually
capped if the primary pump does not
obtain its power from this pair (e.g. if a
variable speed primary pump is
connected to the mains power).
If a parallel pump piping configuration
is used rather than primary/secondary,
loop the White/Yellow
Primary Pump
pair up to connect this to the lowest pair
of contacts on the green Pump/Valve
terminal strip, then connect the two load
pumps in the normal way – this will
bring power to the pump control block.
Pumps can be switched on/off using
the keypad, so there is no need for
temporary pump wiring during
system filling / air purging. If pumps
are hard-wired to the panel during the
system fill/purge phase, re-wire the
boiler pump to the Primary Pump
leads inside the wiring box, to enable
the water flow proving routine to run.
In a new construction application-
use a
construction thermostat – or jumper
with in-line on/off switch – for on/off
management of the boiler. Do not just
pull power from the unit, or its
moisture management routine will be
interrupted
(fan turns at ultra low rpm
for 90 minutes after burner shutdown).
Treat it like a computer, where you do
not just pull the plug when done. If an
“
Insufficient airflow / check vent”
error
signal shows, check for (and remove)
any water in the clear vinyl air reference
tubes. This has been seen occasionally at
construction sites where the boiler has
been repeatedly de-powered wet.
The combined current of all pumps
connected through the on-board pump
relays should not exceed 10 amps.
1.7.2 Power Quality and Electrical
Protection
The DC power supply (VFC 15-150) and
the control board (both models) are each
protected using in-line field replaceable
fuses of 1 amp (slow-blow). The control
circuit board is further protected using
on-board factory repairable fusing.
The principal exposures to electrical
damage:- (a) when wiring of pumps to
the boiler’s pump terminals, avoid
screwdriver contact with the metal
control cover; (b) avoid water or solder
spray onto fan circuitry.
1.7.3 Zone Valve Hook-up
If zone valves rather than pumps are
used to manage multiple heating loads,
then 24V
AC
for the zone valves should
