Monthly Archives: September 2017

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FAT test

Air and water cooled ammonia chillers

Ammonia chillers by Maximus Chillers

Maximus Chillers has years of industry experience with highly skilled engineers. We will guide you to guide you into the future for ammonia chiller service. As HFCs (hydro fluoro carbon) are being phased down, ammonia chillers are becoming more and more popular in non-industrial environments. Ammonia has been a preeminent industrial refrigerant for over 125 years so the technology has got better. See video here

Compressor retrofit for an ammonia chiller

We have recently carried out an ammonia chiller repair for one of our customers and have to say they are very happy! A Manufacturer has given the customer a quote for replacement ammonia chillers- £200,000. The compressor was no longer manufactured. Our service manager therefore made the calculation for a different sized one. Volt x Amps = Kilowatt so we used this equation to determine compressor size. We used the old compressor bolts to fasten to a steel plate with the new compressor bolted to the steel plate. Contact Us

Air cooled ammonia chiller repair

Another company had given our customer an expensive quote. The company attended site and carried out an inspection. Our engineer found the o rings to be leaking on the compressor. The customer chose the option to have the compressor re-manufactured. A worshop or on-site are the two options for the re-build. We had it lifted out and re-built, then lifted back in again. The issue with the controller was that the LCD display had failed- showing the whole screen up in black. We stripped down the controller in our workshop. Then ordered the parts for the controller. Our engineer did the reverse of the strip down and gave all parts a good clean. We plugged it in and there were no further issues. We left it running and cleared site

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Centrifugal Chiller Maintenance

Centrifugal Chillers

Centrifs don’t have as high a compression ratio as positive displacement compressors but they compress a lot higher volume of refrigerant. They are the choice for large tonnage applications. We have a 9 mega watt system that we look after. A common issue with centrifs is surging: when there is low load, the compressor tries to suck, stalls then tries again. This causes the impeller and high speed shaft to rock forwards and backwards causing severe damage. There is a proximity sensor to shut the machine down in this condition but grinding of the impeller against the casting can still occur. After we re-built the compressor we installed controls to shut down the chiller when the process stopped. Should have been like that from commissioning but we were only brought in after the customer started having issues with the installer. Now we have got the machine to settle down- the customer are over the moon  Read More