Requirements; Installation Location Requirements; Burner Requirements - Bosch Uni Condens 8000 F Installation And Maintenance Instructions Manual

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Requirements

4.1

Installation location requirements

The design of installation locations and the installation of the boiler must
comply with local regulations.
The installation location must meet the following requirements:
• In the boiler installation location, an ambient temperature of between
5 °C and 35 °C must be ensured.
• The installation location must be dry and free from the risk of frost.
• The installation location must be equipped with the required
combustion air vents.
• An adequate supply of fresh air must be ensured.
• The installation surface must provide sufficient load-bearing capacity
and solidity.
• The installation surface must be flat and level.
• The size of the installation location must be adequate to ensure
correct operation.
The ventilation requirements for open flue devices must correspond to
IGE/UP10 Edition 4, BS6644 or BS5410 Part 2.
Take into account additional consumers of supply air (e.g. compressors)
when sizing.
When using burners that are operated with a higher volume of excess air
(e.g. premix gas burners), the clear cross-sections must be increased.
• = 1.3: increase values by 20 %
• = 1.5: increase values by 40 %
Floor standing condensing
boiler
UC8000F 800
UC8000F 1000
UC8000F 1200
Table 9 Internal cross-section of the vent
The ventilation design at the installation location must be approved by
the system developer and correspond to IGE/UP10 Edition 4, BS6644
or BS5410 Part 2.
▶ Never install system components that could be damaged by frost
near the combustion air vents.
▶ If necessary, install a device to preheat the supply air
(e.g. a heating battery in the combustion air vent).
▶ Never position objects in front of these vents. Keep the combustion
air vents free at all times.
▶ Never store flammable materials or liquids in the immediate vicinity
of the heat source.
Mechanical ventilation
To prevent continued operation if the mechanical ventilation breaks
down at the installation location, an isolating device must be installed
between the ventilation monitoring system and the wall mounted boiler.
▶ Provide isolating device.
Combustion air vents
Use of windows as combustion air vents is not permitted!
Uni Condens 8000 F – 6720867056 (2016/10)
Clear cross-section of smallest
2
aperture [cm ]
2175
2675
3175
4.2

Burner requirements

Only use specified pressure-jet gas burners with floor standing gas
condensing boilers.
Use specified pressure-jet burners or dual fuel burners for floor standing
gas/oil condensing boilers.
The boiler must be equipped with a burner that is suitable for the boiler.
NOTICE:
System damage through the use of an incorrect burner.
▶ Only use burners that meet the technical requirements of the boiler
( chapter 14.1, page 41).
Any pressure-jet gas burner type-tested to EN 676 can be used if its
operating range matches the boiler specifications. Oil burners type-
tested to EN 267 can be used if they have been approved by the
manufacturer for low sulphur fuel oil (s < 50 ppm) and if their operating
ranges match the specification of the boiler. Only burners that have been
tested and approved for electromagnetic compatibility (EMC) may be
used.
Furthermore, the following points must be observed when selecting
burner or burner control unit:
• Gas burners must be capable of modulation and have modulating
control.
• Oil burners used with boilers with an output of 70 kW or more must
be implemented as 2-stage burners and have at least a 2-stage
control.
• The control range of the burner at a boiler from an output of > 90 kW
must be at least 1:1.8 (i.e. the low load of the burner must not exceed
55 %). The ignition load of the burner must also not exceed 55 %.
• The burner control must ensure that the burner is switched to low
load before a controlled shutdown.
• The output of the burner must only be controlled by the control unit.
Automatic start up of the burner at full load following a burner
demand without taking the requested load into account is not
permitted!
Burner selection and settings
The sizing and settings of the burner have a significant influence on the
service life of the heating system. Every load cycle (burner on/off)
causes thermal stresses (loads on the boiler shell). The number of
burner starts must therefore not exceed 15,000 per year.
The following recommendations and settings are designed to meet this
criterion ( chapter 5.3, page 15 and chapter 7, page 25).
If this figure is however exceeded:
▶ Get in touch with the sales or customer service department of the
manufacturer.
It must be possible to check the number of burner starts, e.g. at the user
interface, third-party control unit, building control system or burner
control unit.
Requirements
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