The Service & Maintenance of Industrial Refrigeration Plant
Past
Ammonia has been an established, pre-eminent industrial refrigerant for over 125 years. Ammonia is used in industrial refrigeration applications such as food production. CFCs, such as Freon, became popular in the 1930s due to their low toxicity. The chlorine in the refrigerant was found to have caused a hole in the ozone layer. Therefore, they have now been phased out. Non-chlorine, low toxicity, HFCs were developed to replace the CFCs
Present
HFC refrigerants have a high global warming potential, so they are being phased down to 21% by 2030
HFO refrigerants, such as, R1234ze when they leak, go through the weather system and end up in the sea. They have been reported to be harmful to marine life. These refrigerants are used for chilled water and process applications
Ammonia is the best choice of refrigerant in service for industrial applications
Future
Between now and 2030 ammonia will increasingly be in service in non-industrial applications, such as, the cooling facilities and the cooling of buildings. New ammonia chillers are simpler in design, therefore competitive in price to HFC chillers. The higher initial cost is paid back in electricity savings within 2 years- then they become cheaper. They use less electricity because ammonia has a latent heat bubble 5 times bigger than other refrigerants. That means 5 times more refrigeration effect, per kilo of refrigerant, than HFC refrigerants
Case Study
The photo is during an industrial refrigeration visit following no maintenance for a year by the end user
Leak Detection System Calibration
As a matter of urgency we calibrated the ammonia leak detection system. It was in fault because of ammonia leaking over a long period of time, throwing it out of calibration. A working ammonia warning system was the most important part of this visit so far!
Compressor 'o' Ring Leaks
The ammonia was leaking from the 'o' rings on the compressor. This type of problem occurs more often on the discharge. Due to the heat, the 'o' rings become plastic like and flat- causing them to leak
Compressor Remanufacturing
We lift and shifted the compressor to be remanufactured in our workshop. The rotors, with bearings, slide out still pressed into the casting, so it was straight forward to strip the compressor, replace the 'o' rings and shaft seal, then rebuild the compressor. Read More about compressor remanufacturing
Condenser Fan Replacement
On a running the plant, we found that most of the condenser fans needed replacement. The long period of time that the chiller had been off had allowed water to ingress into the fans. To service the industrial refrigeration system, the fans and scaffolding were sent to site and the fans were replaced
Industrial Refrigeration Maintenance
The Pipework
The use of steel makes industrial refrigeration maintenance different as opposed to HFC chillers. Ammonia corrodes various metals and alloys. Steel, however, works well with ammonia.
HFC
These chillers are prone to leaks on the copper pipework. On the condenser, the copper expands and contracts- eventually rubbing through against the steel frame. Vibration related leaks are also common
Ammonia
On an ammonia system, steel that is freezing then thawing on defrost or off cycles creates rapid rust formation and can lead to catastrophic failure of the pipework. Steel that is permanently frozen creates slower rust formation as the ice slows the oxidisation process. On an industrial refrigeration maintenance visit, our engineers carry out metallurgic testing to gauge the integrity of the steel
Industrial Refrigeration Maintenance Tick Sheet
We at Maximus Chillers believe our detailed industrial refrigeration maintenance Tick Sheet is the best in the industry. It has taken years of development, every time there is a change in the industry the Tick Sheet is updated. It has all the values and adjustments that can be checked to ensure the optimum, energy efficient performance of your plant. When an engineer is struggling during the fault finding, he uses the Tick Sheet as a reference- the fault will be on there somewhere!
Oil Return During the Industrial Refrigeration Maintenance
Oil used to lubricate the compressor and ammonia are non miscible- that is to say the refrigerant does not entrain the oil round the system and back to the compressor
Reciprocating Compressors
In an industrial refrigeration system using reciprocating compressors: the oil mainly stays in the compressor
Screw Compressors
Screw compressors make the maintenance different: the oil is discharged, so an oil separator is vital to the oil return
Oil Separator
Put simply: an oil separator make it as easy as possible for a gas to get through, while as hard as possible for a liquid. The oil drains to the bottom of the vessel and is pumped to above discharge pressure into the screw and bearings
Oil Harvesting
During the industrial refrigeration maintenance visit: oil is harvested from the low side of the system. On modern systems, the oil return sensors and return solenoids, ensure most of the oil gets back. This is assuming the system is running otherwise okay- if there is refrigerant shortage- oil return issues will follow
0161 370 7193
service@maximuschillers.com
Industrial Refrigeration
UK Quality Overseas
Maximus Chillers is a sought after company in the field of industrial refrigeration around the world because the world knows that the United Kingdom means quality in engineering. The UK has a long history in industrial refrigeration. The knowledge of which is invested in our engineers. We have international customers in the USA, Moscow and the Middle East
International Shipping
We have supplies sent out to site prior to site visit, there are tools and equipment available on site too. This means less to ship for the repairs. Industrial refrigeration suppliers are not round the corner while on site, so each job is meticulously planned. All the smaller things like fittings and ammonia grade Loctite are taken with us to ensure the job goes smoothly
Global Technical Support Desk
Our customers enjoy the full support of an industrial refrigeration Technical Support Desk. They allow for the time difference to decide the best time for a phone call. Emails are answered real time or when the office opens in the morning. Technical information such as user manuals can be sent out as a PDF allowing the customer to understand the front end user screens
Industrial Refrigeration Upgrade
No job is too big for this industrial refrigeration company. We upgrade your existing plant with bespoke, state of the art controls and components. This optimises energy efficiency and reduces downtime. We can arrange for the works to be carried out during factory shutdown for minimum disruption. Most customers, however, have redundant systems- so works can be carried out with no disruption at all
Future Proofing
Ammonia already is a future proofed refrigerant, way ahead in performance to other refrigerants. The industrial refrigeration upgrade will give you a long and cost effective future for your plant. All the money required to buy new plant can be used more effectively in the running of your business
0161 370 7193
service@maximuschillers.com
Call Out
Schedule a site visit today!