What are the causes of failure in the auxiliary oil pump of a Carrier screw chiller?
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This post was last edited by xhkf on 2012-8-17 at 18:03. The chillers we use are two units of the Carrier 30HX110A (B) model; they were put into use in 2008. These chillers supply chilled water for the air separation system. The auxiliary oil pump is used only to establish a preliminary oil pressure during startup, while during normal operation, the oil for lubrication is supplied based on the pressure difference between high and low pressures. Carry out regular maintenance as instructed by the after-sales service. The operating time for all of them is around 15,000 hours; three oil pumps have already been damaged. Each time an oil pump fails, the unit is shut down normally before being restarted – this happens during maintenance tasks such as oil changes or when the three filters need to be replaced. In such cases, the unit cannot start properly, as the oil pump is unable to generate the necessary pre-lubrication pressure; it also becomes hot to the touch. After checking, the after-sales staff found that the output signals from the control board were normal, and concluded that the damaged oil pumps needed to be replaced with new ones. Has anyone used a machine of this model? Do such problems occur often? Recently, the machine stopped again in the middle of summer due to an oil pump issue. :(
This post was last edited by xhkf on 2013-1-20 at 18:15. According to the after-sales staff, the oil pumps used to be imported from abroad, with each one costing over 10,000; now that they are manufactured domestically, their price has decreased, and they shouldn’t break after just two or three uses. If the condensation pressure is too low, the oil pump will still start automatically, which will increase the number of times the oil pump operates. In future operations, make sure that the oil pressure difference is not too low.
It seems that not many problems arise with this type of ice machine; we’ll just have to wait a long time for the spare parts to be replaced.
In most cases, this is due to issues with the design and selection of the oil pump; after replacing the filter, the system resistance decreases and the flow rate increases, which may lead to overload and damage to the pump.