Troubleshooting Temperature and blower issues

Resolving The Problem

1. To begin troubleshooting, check the following top issues. If your issue is listed, select the link, otherwise, proceed to step 2.
   
   

   	Temperature problems
   	Blower problems

   
   BladeCenter uses blowers to cool the chassis. The blowers can each move up to 325 cubic feet per minute (CFM) of air maximum (150 CFM each in standard operation). BladeCenter supports predictive blower failure by monitoring the blower RPM. BladeCenter supports Hot-swap, redundant and support fan speed control.
   
   
   Redundant cooling is by backward curved impeller blowers. Airflow is from front to rear. In the enterprise/entry chassis, the blowers are located in the rear of the chassis and draw air from the front to the rear. Blower speed control will be via a thermistor monitoring inlet air temperature. System devices will also be monitored. All air entering the server will pass through the processor heat sinks. An air restriction (baffle) must be used when a processor isn’t used in one of the processor positions.
   
   If the management module fails, the speed of both blowers is increased to maximum. If one power supply fails, both blowers increase speed to maximum speed in order to ensure maximum air flow passes through the remaining power supplies. The telco chassis has four hot-swappable blowers connected to the blower-housing assemblies blind mated to the docking board. Each telco chassis has two blower-housing assemblies. The blower module handle provides a tool-less removal, installation and retention of the blower modules. The system is architected to provide sufficient cooling for the telco chassis with only three of the blowers operating. It should be noted that there is a backflow device in all of the blowers which will prevent the system from drawing air in via the exhaust port of a blower that has failed. Blower speed is controlled via voltage level signal from the management module. The blower provides speed control feedback to the management module via a tachometer output signal.
   
   The rear of BladeCenter (Type 8677) provides bays for power, management modules, switch modules and blowers. An information panel is also present. The rear information panel has the same indicators as the front information panel. To maintain proper system cooling, all module bays must contain either a module or a filler module; all slots must contain either a blade or a filler module.
   
   
   
   This schematic shows the air flow path of the enterprise/entry chassis. The telco chassis follows a similar design. Air enters the processor blade and passes through the processor heat sinks. It then passes into the rear of the chassis via 3 paths. Air passes above the midplane, through the center of the midplane, and below the midplane. The air at the bottom passes up through the modules and power supplies and into a common plenum. Air at the top of the chassis passes down through the upper modules and power supplies and into the common plenum. Air also passes through the midplane and into the common plenum. Air then passes into the two blowers and is exhausted out the rear of the chassis. There are backflow dampers on the blowers to prevent air recirculation into a failed blower.
   
   
   
   
2. Check lightpath diagnostics for your BladeCenter:
   
   

   	BladeCenter (Type 8677)
   	BladeCenter JS20
   	BladeCenter HS20
   	BladeCenter HS40
   	BladeCenter T (Type 8720, 8730)

   
   
3. If a new option has been added and your system is not working, complete the following procedure before using the troubleshooting charts:
   1. Remove the option that you just added.
   2. Run the diagnostic tests to determine if your system is running correctly.
   3. Reinstall the new device.
      
      
4. Make sure that the BladeCenter unit has the latest level of firmware code installed.
   
   
5. If these steps have not solved your problem, refer to "Need more help?"

Note: See "Parts listing, BladeCenter Type 8677" of the BladeCenter Hardware Maintenance Manual to determine which components should be replaced by a field service technician.

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Note: See "Parts listing, BladeCenter Type 8677" of the BladeCenter Hardware Maintenance Manual to determine which components should be replaced by a field service technician.

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