Bunn Fast Cup Series Service & Repair Manual page 58

LEFT PANEL
Solid State Relay (SSR)
Purpose: The solid state relay with led indicator is
made up of solid state components which have no
mechanical contacts or moving parts which extends
the life of operation. The SSR switches A/C power to
the tank heater and provides electrical isolation from
the low input D/C control circuit. The green LED is a
visual indicator used for easy identification of the input
control or operation of the SSR.
Note: One SSR per boiler tank/heater.
TEST INSTRUCTION
Note: First, cool the tank module down in tempera-
ture before testing solid state relay so you don't
accidentally create an over temperature error which
could result in a tripped limit thermostat.
Tank Module Cooling Instruction
Step 1: Enter Service Technician Mode and select
Service icon.
Step 2: Select and enter the Heaters tab.
Step 3: Disable Finish, Pre-Heat and Inlet Heater
Control. This will temporarily stop the
heating control from turning ON because of
low tank temperature.
Step 4: Exit Heaters tab and enter Water System
tab.
Step 5: Touch and hold Hot Water Bypass Valve
to start cooling down the tank module.
The valve test time runs a maximum of 10
seconds.
Step 6: Next, go back to the Heaters tab. Read all
three tank temperature's and ensure they
are cooled down below 150° F. from 200°F.
Step 7: The SSR control can be tested with the SSR
being disabled in Step 3. Touch the corres-
ponding Finish, Pre-Heat or Inlet Heater
SSR button to activate the control.
Step 8: An LED control status indicator will illumi-
nate on the SSR to indicate input/operation.
Heater A/C Current 10.8 Amps +/- 5%
will be displayed at the bottom of the Service
Screen. SSR & Boiler Tank/Heater Operat-
ing correctly.
SERVICE
Heatsink
Block
Load Side
2
4
58
Control Side
6
ON
8
10.8 amps
7 & 10
5
Continued >
3