7.11 Noise When Heater Is Running; Burners Do Not Operate Cleanly; Yellow Flames When Operating; Protecting The Environment - Bosch 520-HN -L Manual

30 | Protecting the environment

4.Be sure to run only one major fixture at a time with this water
heater. Opening too many taps at one time can disperse water
flow resulting in diminished flow or pressure at all outlets

7.11 Noise when heater is running

If the water has a high mineral content, the heat exchanger may
be scaled internally. This restricts the water path, causing the
water to boil resulting in noise and overheating. To descale the
heat exchanger, consult section 5.6 on page 19.
7.12 Burners do not operate cleanly; yellow flames
when operating
1.Verify that gas type indicated in the rating sticker located on
the heater's right hand side, coincides with the gas type you are
using. NG is a natural gas unit and LP is for liquid propane (see
chapter 2.2).
2.2. For proper combustion at high elevations the inlet gas
pressure must be set at installation to the values in table 3 on
page 12 (while operating at maximum BTU). A gas pressure
reading is needed to proceed further. Contact your original
installer or a local gas technician to obtain this reading.
3. Combustion air is inadequate. Ensure that adequate
combustion air is being supplied to the unit in accordance with
requirements in the installation manual. See chapter 3.3.
4. Verify that the water heater is vented properly. Ensure that
the venting meets requirements in chapter 3.6.
5. If the burner flames burn yellow or orange the burners must
be removed from the unit and cleaned. Once the burners are
removed, the fins in the top of the heat exchanger can be
accessed from below and brushed or vacuumed clean. Consult
service bulletin CT-13 on www.bosch-climate.us for removing
and cleaning the burners.
8 Protecting the environment
Packing
The packing box may be fully recycled as confirmed by the
recycling symbol .
Components
Many parts in the heater can be fully recycled in the end of the
product life. Contact your city authorities for information about
the disposal of recyclable products.
Saving water resources:
▶ Make sure you close all the taps after any use. Avoid leaving
the taps dripping. Repair any leaking tap.
6 720 644 942 (2014/11)
▶ Define the temperature you want. This way you have the
precise water flow needed (mixing cold water to regulate
temperature will increase the water flow with consequent
waste of water).
520 HN