Gas; Gas Tightness Test; Natural Gas Knocking Monitoring Equipment; Standard - Viessmann ESS CHP Overview

Gas

3 Gas

3.1 Gas tightness test

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Function
Delivery

3.2 Natural gas knocking monitoring equipment

Article number
Version
Function
Delivery
Subject to changes due to technical improvements
CHP accessory range – 01/2010
CHP module type
EM-18/36, EM-50/81, EM-70/115
Tightness tester, including installation in the gas train or module control panel
The gas tightness tester consists of a pressure and monitoring PCB for installation in the gas train of the
CHP module. It is suitable for gas trains with two safety valves and monitors the safety function of the
valves following shutdown. The tester establishes any unacceptable leak in any of the gas valves and
prevents the CHP module from starting up if there is a fault.
According to EN 746-2, a tightness test should be carried out from 1200 kW heating output and above. In
DIN 33831-2 it is recommended from 390 kW and above.
Integrated into the CHP gas train
CHP module type
EM-50/81, EM-70/115, EM-140/207
EM-238/363
• For natural gas with a methane count < 75
• With a methane count between 80 and 75, provide output reduction!
• Knocking control fitted in the module or module control panel
If the methane count of the fuel gas (not to be confused with the methane content!) is below the
permissible level for the engine, after successful ignition the thermodynamic properties of the gas will
cause an additional ignition of the air-gas mixture outside the standard combustion range. This results
in significantly faster combustion with several flame fronts. Where these flame fronts meet, powerful
pressure waves are created whose sound emissions are heard as knocking noises.
Knocking causes much greater wear and leads to engine damage; it should always be prevented.
For this purpose, the natural gas knocking monitoring equipment is provided, which reliably prevents
knocking sounds as part of the CHP module control. If knocking persists, the output will decrease. If this
measure is not successful either, the engine must be switched off.
• For EM-50/81, EM-70/115, EM-140/207 in separate control panel
• For EM-238/363 integrated in the CHP module or module control panel
ESS Viessmann
710-00-0052 7411168
ESS Viessmann
710-00-0050 7417755
710-00-0051 7411169
ESS Energie Systeme & Service GmbH
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