Troubleshooting - Bosch TRONIC 5000C Pro Installation Manual And Operating Instructions

22 | Troubleshooting

7 Troubleshooting
DANGER: Risk of electric shock!
B Always switch off the electricity supply to
the unit before you remove the cover.
Cold water only – Neon light off
Flow rate is too low
Plumbing crossover
The flow transducer is not
spinning
No electricity at the heater
or one of the supplies has
failed
One or more of the heating
module thermal cut-outs
has tripped
The power supply voltage
has dropped
Tab. 10
6 720 646 951 (2011/09)
Verify the flow rate out of fixture is at or above the minimum activation rate
required for the unit to activate. (Activation rates: WH17 = 0.6 GPM, WH27 = 0.8
GPM).
To test for a plumbing crossover, turn off power supply to the heater. Close
installer supplied cold water shut off valve (if none installed, install before
proceeding). Open all hot water taps supplied by the heater. Wait 5 minutes and
check all taps. Any water running is a sign of a plumbing crossover. Consult a local
plumber or service person for help in correcting a plumbing crossover. To return
the heater to service, reinstall cover, open the inlet water supply to the heater and
open all hot water taps. Let all taps run until there is no air coming out of the
fixtures. Shut off all hot water taps. Turn power supply on to the heater. Return
heater to service. (This procedure will prevent the heating elements from burning
out).
Turn off the power supply to the heater and remove the cover. Observe if the flow
transducer "spins" when the water is turned on. Please note the flow transducer
spins at a high speed and can appear to be stopped when actually spinning. It is
recommended to observe the flow transducer without water flowing, then turn on
a hot water tap while observing the flow transducer. If the flow transducer is not
spinning, remove and flush flow transducer, noting the Do's and Dont's on page 20.
See the technical support section of www.bosch-climate.us for more detailed
instruction on removing the flow transducer.
Have a licensed electrician verify proper wiring and adequate voltage on the
terminal block inside the water heater. See the "Electrical connections" section on
page 14 of this manual.
Turn off the power to the heater, remove the cover and locate the thermal cutouts
on the top of each heating module. Check for continuity through each cutout.
(Less than 0.5 Ohms). A continuity value greater than 0.5 Ohms indicates that the
cutout has tripped or is faulty. A cutout will only trip in exceptional circumstances
and it is essential that the cause is determined and resolved. Verify the heater's
inlet filter screen and all outlets served by the heater are clear of debris. Ensure
the heater is not being fed preheated water. This water heater is designed for cold
water feed only.
Contact Technical Support 800-798-8161 for further instructions.
This is likely an issue with the incoming power supply. Have a qualified electrician
measure voltage on the water heater's terminal block while operating at maximum
flow and maximum temperature setting. The WH17 & WH27 models are rated for
240V and will also operate at 220V or 208V with reduced maximum flow rate.
Important: If you are unable to perform the tasks listed
below, or need additional assistance please contact your
original installer/licensed electrician.
US
Copyright