UPS Overheating


UPS overheating – Why? And How to stop it.

Causes of UPS overheating explained:


Has the Air Conditioning in the UPS environment failed? More commonly is the A/C still working although not operating efficiently causing the ambient temperature to rise? This will quickly cause the UPS internal temperature to gradually rise above optimum and then overheat. At that point the UPS will go into internal bypass and finally stop dropping the load.

Debris & Dust

Debris and Dust build up has the effect of causing UPS components to overheat , which because it is unseen , will happen over time and between service visits. If you have had work carried on your site where dust and debris have been airborne, then carry out a UPS inspection to ensure that any Dust and Debris is cleaned from inside your UPS by a UPS trained engineer. If you do not remove dust and debris, there is a serious FIRE risk as well as causing the UPS to overheat .

UPS Fans

Each UPS has many fans inside. You can’t see then but you can hear them. Fans have a life span and do fail. Usually, one fan at a time.
The more fans that fail, the more quickly the UPS will begin to overheat. The increase in the internal temperature of the UPS will ramp up slowly at first and then once the second fan fails , it will be enough to trigger UPS alert alarms. At that point your UPS will be over heating. Replace ALL the fans, as soon as one fan fails.

UPS Load

The load should always be balanced equally across the 3 phases.
If the UPS out put load is placed on only ONE phase of the UPS and virtually nothing on the other TWO phases then this imbalance will cause your UPS to overheat and the UPS will fail overtime when you least expect it.
Also never run a UPS with the load above 75% continuously.
NEVER run a UPS at 100% or your UPS will fail after overheating.

Enclosed Space

Never place a UPS in an enclosed space that has no free flow ventilation to air. Ensure that the UPS has free space on all sides to allow free air flow. NO free flow cool air and the UPS will overheat.

Smell of rotten eggs

When old UPS batteries begin to fail, they can leak and give off a rotten egg smell. Your UPS may still be operating but you MUST replace ALL the batteries especially if they are over 4 years old or have been operating in an over warm or very cold environment. Failure to do so will put a strain on the UPS battery charger and will cause the UPS to overheat. This is also a MAJOR FIRE risk.

There is also a health & safety issue for both leaking ACID and Air borne pollution.

ACT QUICKLY – Call your local UPS engineer.

Water Intrusion

Has there been a water leak recently? If any water has entered the UPS it can case some of the UPS fuses to trip. The UPS may continue working although it is worker much harder trying to compensate for the failed sections. This will cause the UPS to overheat and again is a FIRE risk. Call your local UPS engineer and ask them to check the condition URGENTLY.

Call Power Continuity on 0845 055 8455
For UPS Systems service

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