Repair or replace?

THEY TIRELESSLY TOIL 24/7 to keep servers and equipment operating in tip-top condition for your clients. If they fail, the consequences can be catastrophic. We’re talking about cooling systems – the unsung and often unseen heroes working without a break behind the scenes of data centres up and down the country.

Advice and opinions vary on how to best keep these workhorses running at peak performance. If there’s an issue, a manufacturer is likely to recommend a replacement, and a service company will steer you towards a repair. But which is the better option?

Whether you have an in-house facilities management team, or have contracted a company specialising in servicing this type of close control equipment, there are several factors to be aware of.

Weighing up replacement vs repair
With new and innovative systems coming on the market at regular intervals, a decision made two years ago to repair rather than replace might be a different one if made today. With a continuing drive to improve energy efficiency by manufacturers, newer systems can deliver return on investment quickly; and facilities managers can spend a lot less time spent hunting around for obsolete or decades-old spare parts.

This is particularly true when weighing up Power Usage Effectiveness (PUE) and reliability factors of new systems.

Replacing older fans to deliver energy savings
Older style AC fans can need more TLC, with money spent on replacement belts and pulleys, drive losses and consumables. They can be easily retrofitted with more modern EC (Electronically Commutated) fans, which have an integral Permanent Magnet Motor (PMM). With no belts or pulleys to maintain, EC fans are also more energy efficient through their use of permanent magnets.

The estimated payback time for retrofitting EC fans in place of more traditional AC fans is only 18 months. Both AC fans and EC fans, if properly serviced and maintained, can work smoothly for 25 years and more.

Replacing units using R-22 as a refrigerant
R-22 (also known as HCFC-22) was the choice of refrigerant in many air-conditioning systems for decades. A hydrochlorofluorocarbon, R-22 contains ozone-destroying chlorine, with the Montreal Protocol of 1992 setting out its ambition to phase out its use across the globe. As a result, newer air conditioning systems run on alternative refrigerants. However, many older ones, especially those from the mid 1990s and earlier, still run on R-22.

You can tell which type of refrigerant your system is running on by checking the F-Gas log book. This book will list the type of refrigerant and the charge in kg in your equipment. Alternatively, the data plate attached to the unit will typically display the type and quantity of refrigerant in the system.

Since the beginning of 2015 in the UK and in all EU member states, the use of R-22 has been completely banned. Therefore these older systems can no longer be refilled with R-22 refrigerant, and they’re not compatible with the more modern non-ozone-depleting alternatives such as R407C, used since the mid 1990s. As a result equipment using R-22 refrigerant will need to be replaced rather than repaired when it starts to fail.

Repairing and replacing system components
The biggest challenge often faced by facilities managers and service companies is that of spare parts. Older components are often made obsolete by manufacturers in the intervening years – or even decades – since a system was commissioned. Spares for controls are particularly notoriously difficult to source, leaving little choice but to replace rather than repair a unit.

Some organisations, such as DencoHappel, keep stocks of these older spare parts, making it possible to repair age-challenged systems to keep them up and running.

However, the switch to new, more energy efficient inverter-driven units and systems can be far preferable to patching up decades-old units.
The energy efficiency of these newer inverter-driven units and systems deliver relatively short payback times and a good return on investment; particularly when reliability over a much older system is considered. This is especially relevant due to the considerable recent technological advances which have impacted the efficiency and Power Usage Effectiveness (PUE) of new systems.

Keeping a regular maintenance schedule
Running at optimum performance every second of the day can be wearing on any system, and air conditioning is no exception. Without regular servicing, your erstwhile reliable and efficient system can suffer from reduced efficiencies, breakdowns or failures.

To keep unexpected and costly repairs to a minimum, close-control systems should be serviced typically between twice and four times per year. In most commercial applications regular servicing will be an obligation, as maintenance will fall under the requirements of the F-Gas regulations, which come complete with set service criteria. Regardless of when or whether service is due, you can look, listen and feel for these tell-tale signs of any potential issues:
 Excessive noise
 Vibration
 Loss of cooling, with higher than normal
temperatures in the data centre
 Increase in energy usage

Knowing the cost of doing nothing
Operational costs are always a key factor, but it is wise to ensure your budget allows for effective maintenance, as system neglect will only lead to costly failures in the end.

A poorly cared for system can overheat, resulting in the loss of the clients’ connectivity to their data services and stored data; meaning not only a very unhappy and inconvenienced client, but a huge bill as well. Such insurance claims can be staggeringly large when compared to the cost of keeping the equipment properly maintained.

Choosing your equipment provider and service provider
With equipment manufacturers likely to recommend a replacement, and a service company steering you towards a repair, how can you get an unbiased view?

One option is to choose an organisation that offers both. DencoHappel are one of the few OEMs who can offer clients across the UK everything from new equipment design and manufacture, and installation, commissioning, service aftercare and a spares resource in a “cradle to the grave” service.

Whether you opt to use a pure service company or an organisation with multiple strings to its bow, you should check the service provider’s credentials. For example, check they have F-Gas certification, the right health and safety systems, qualified engineers with training provisions and records, and up to date insurance certification and cover. It’s worth knowing that a 24/7 call-out service is also offered by most service contractors to their contracted clients.

Understanding when to repair and when to replace
By upgrading older equipment you can take advantage of the efficiency provided by inverter driven compressors, EC fans and advance control systems such as the Multi-DENCO system from DencoHappel, where the energy cost savings over old equipment can be dramatic.

Companies such as DencoHappel are ideally placed to advise anyone with existing equipment about how long they can run units on repairs and spares, and when it becomes cost-efficient to replace a system.

The key though, is not to let it get to a crisis point. Regular servicing and maintenance is the crucial factor in making sure your decision to repair or replace is borne out of choice, not out of necessity.