Hoshizaki Steelheart Series Service Manual page 14

Factory Default Temperature Settings:
a) Rail Control Dial: 5
Day Mode - Rail Cover(s) Open (27°F (-2.8°C))
Night Mode - Rail Cover(s) Closed (35°F (1.7°C))
b) Cabinet Control Module: 35°F (1.7°C)
c) Display Scale: °F
Note: There is a minimum 2-min. Comp on time and 2-min. Comp off time.
For further details, see "III. Controls and Adjustments."
1) Unplug the appliance from the electrical outlet.
2) Remove the front panel and left side panel.
3) Plug the appliance back into the electrical outlet. 6-hr. defrost timer starts.
4) Startup/Cool Down – Rail and cabinet temperature above setpoint. RCD, RTh and CTh
are calling for cooling. Comp, ConFM, EvapFM(s), CabFM(s) and CabFMR energize.
Cabinet temperature and cooling icon are displayed on the CCM.
a) RTh, RCD, and RCM Diagnosis: Day Mode: With rail cover(s) open and RTh calling
for cooling, Comp, ConFM, EvapFM(s), and CabFMR energize.
If not, confirm that the RCD is in the correct setting position (5). Next, check the
resistance between RCD red and black wires. Resistance value should be between
3.76-5.64K ohm. If RCD is out of range, replace RCD. If RCD is in range and rail
temperature is above setpoint, check RTh. See "II.C. Thermistor Check." If RTh is
out of range, replace RTh. If RTh is in range, check for 115VAC at RCM line 2(L)
black (BK) wire to RCM neutral 3(N) white (W) wire . If 115VAC is not present,
check breaker/fuse for an open circuit. Reset or replace as needed. Check for loose
connections on line 2(L) black (BK) wire and neutral 3(N) white (W) wire and power
cord connections. If 115VAC is present at RCM 2(L) black (BK) wire and neutral 3(N)
white (W) wire, check for 115VAC at RCM 1(C) violet (V) wire to RCM neutral 3(N)
white (W) wire. If 115VAC is not present, replace RCM.
b) Comp/ConFM Diagnosis: Comp and ConFM energize. If not, confirm 115VAC at
RCM 1(C) violet (V) wire. Next, check for 115VAC from both sides of Comp external
protector red (R) wire and Comp terminal to neutral (W) wire. If 115VAC is present
on one side and not the other, allow time for Comp external protector to cool and
reset. If Comp external protector does not reset, replace Comp external protector.
If 115VAC is present on both Comp external protector connections (red (R) wire
and Comp terminal) to neutral white (W), check Comp run capacitor, PTC relay,
and Comp motor windings. Replace as needed. If ConFM is not energized, check
ConFM fan blades for binding and motor winding continuity.
c) EvapFM and CabFMR Diagnosis: EvapFM(s) and CabFMR energize.
If EvapFM(s) do not energize, check for 115VAC at RCM 5(F) dark blue (DBU)
wire to neutral white (W) wire. If 115VAC is not present and Comp and ConFM are
energized, replace RCM. If 115VAC is present, check EvapFM(s) blades for binding
and EvapFM(s) continuity. If defective, replace EvapFM(s). Confirm 115VAC at
CabFMR dark blue (DBU) wire to neutral white (W) wire. If 115VAC is not present,
check wiring from RCM.
14