What is an emergency air situation?
An emergency is any sudden, unplanned loss of compressed air that stops or threatens production, safety or a critical process. The most common causes we see are:
- A compressor trip that cannot be reset, such as an airend seizure, motor failure or high discharge temperature shutdown.
- Dryer failure that sends wet air into instruments and process lines.
- A shutdown or overhaul that overruns and leaves the plant without its main machine.
- Electrical faults, transformer problems or long power interruptions.
- A sudden rise in demand from a new line or an urgent job that the installed capacity cannot meet.
- Site work, such as an urgent coating or repair job, that needs portable air immediately.
The customer’s own definition of urgency matters. A pharmaceutical plant losing instrument and process air in the middle of a batch has a different risk from a workshop that cannot run its impact wrenches. The record should state the actual impact the customer described, not a dramatic label.
Why emergency records must be precise
Many suppliers advertise “fast response” or “24-hour support” without evidence. A useful record does the opposite: it shows what happened in a real case, step by step, and what limited it. That gives plant engineers a realistic picture of how temporary air can be arranged and what they must prepare on their side.
Four different elapsed times are often confused:
| Interval | Starts | Ends | Who mostly controls it |
|---|---|---|---|
| Acknowledgement | Request received | Engineer responds | Supplier |
| Decision | Duty details received | Customer approves the option offered | Both parties |
| Mobilisation | Approval given | Machine arrives at the site gate | Supplier, transport, distance, road and permit conditions |
| Air available at duty | Arrival at gate | Air at required pressure and quality at the user | Both parties: access, positioning, tie-in, fuel or power |
A record that only quotes the total time hides where delays really came from. Gate passes, unloading equipment, a missing tie-in point or a power cable that is too short can take longer than the road journey.
Confirming the duty before dispatch
The quickest way to lose time in an emergency is to send the wrong machine. Before allocating equipment, the service engineer confirms:
- Flow. The actual demand, not just the rating of the failed compressor. A failed 500 cfm machine may have been running at part load, or it may have been one of several running together.
- Pressure. The minimum pressure needed at the critical user, plus losses through hoses, treatment and the tie-in. Most plant air runs at about 7 bar (101.5 psig); some processes need 10 bar (145 psig) or more.
- Air quality. Whether the air must be dried, oil-free or filtered to a particular ISO 8573-1 class. Portable oil-injected units normally need an aftercooler, separator, dryer and filters before they can feed instrument or process air.
- Drive. Diesel if no suitable electrical supply is available; electric if there is a supply of adequate capacity and a safe connection point.
- Site conditions. Access route, ground, space, ventilation, exhaust direction, noise limits and whether the unit will run indoors.
- Duration. A few days of cover, or weeks while an airend is rebuilt.
Where the requested duty cannot be met with the equipment available, the record should say so plainly, along with what alternative was offered.
What the site needs to prepare
Emergency air arrives faster and starts sooner when the site has:
- A named person who can approve the order and sign gate passes.
- A clear, level, ventilated position for the machine, with access for a truck or crane where required.
- A tie-in point on the header with an isolation valve and a suitable connection, ideally fitted in advance as a standby provision.
- For electric units, an incoming supply of adequate rating, with a qualified electrician for the connection.
- For diesel units, an arrangement for refuelling and a safe fuel storage position.
- A way to isolate the failed compressor so the temporary air does not backfeed into it.
Plants that depend heavily on compressed air benefit from planning this before anything fails. Our business continuity and temporary air pages cover standby design in detail.
Commissioning and acceptance
“The compressor has arrived” is not the same as “the plant has air”. Commissioning a temporary machine includes checking oil, coolant and fuel levels, confirming hose ratings and whip restraints, setting the pressure, checking that the aftercooler and drains work, and confirming pressure at the critical user rather than only at the compressor gauge. Where treatment is fitted, dew point and filter differential pressure should be checked once the system has stabilised.
Acceptance should be recorded by the customer: the time air was available at the required pressure, any limitations (for example, reduced pressure at one branch) and any items still open.
Keeping temporary air running
An emergency job often becomes a medium-term hire. During that period the machine needs routine attention like any other. On our hire jobs we change oil and service every 300 running hours. Where operators are supplied for round-the-clock duty, maintenance and breakdown support should stay in one scope throughout. The record for a long hire should log running hours, fuel, services, any alarms and any interruptions, including those caused by site conditions.
Our emergency and breakdown experience
We describe our work factually and without customer names. We have supplied compressors on breakdown to leading pharmaceutical manufacturers in Hyderabad and Telangana, and we have supplied compressors to leading companies across sectors, covering new and used machines, long-term rental and breakdown cover. Our other recorded projects include:
- An urgent coating job at a steel plant in Andhra Pradesh: a 450 cfm diesel portable compressor on round-the-clock hire with operators on 12-hour shifts, oil changed every 300 hours and breakdown support included.
- A thermal power project in Karnataka: a 400 cfm electric compressor with a 160 kVA generator on hire, commissioned within one to two days of arrival, with operator training and preventive and breakdown maintenance.
- A power-plant project: two 450 cfm units at 150 psig (10.3 bar) and one 400 cfm unit at 100 psig (6.9 bar) on hire, with operators able to run and troubleshoot them and servicing every 300 hours.
None of these establishes a standard response time. Every emergency depends on equipment availability at the time, distance, access and how quickly the site can receive and connect the machine.
Common reasons emergency air is delayed
| Cause | Effect | How to prevent it |
|---|---|---|
| Flow or pressure not confirmed | Wrong machine sent; second trip needed | Send nameplate photos and actual demand at the first call |
| No tie-in point | Pipe work needed on arrival | Fit a valved standby connection on the header in advance |
| Approval delayed | Machine waits while paperwork is completed | Agree an emergency purchase route beforehand |
| Gate and permit delays | Truck waits outside the site | Inform security; prepare passes on the order |
| Inadequate electrical supply | Electric unit cannot start | Check supply rating or choose diesel |
| Air quality not addressed | Wet or oily air reaches process | Specify dryer and filtration with the order |
How Reddy Compressors helps
Reddy Compressors is an independent multi-brand specialist based at Tarnaka, Secunderabad, serving industry since 2002. We sell, rent and service compressors of ELGi, Atlas Copco, Ingersoll Rand, KAESER, Chicago Pneumatic and other brands, and we are not an authorised dealer of any of them. We have tie-ups with all major and reputed brands. Our own rental fleet covers 50–2,000 cfm at 2–30 bar (29–435.1 psig), diesel and electric, with hoses and air treatment where the duty needs it.
Our team of over 20 service engineers and technicians covers Telangana and Andhra Pradesh, and we supply rental compressors and spares across India with project-based support where feasible. When a compressor fails we can arrange temporary air, diagnose the failed machine, supply parts identified from its nameplate and carry out the repair or overhaul. Our sister business, Reddy Generators, under the same management, can supply generator sets where the site also needs power.
What to send us
- Site location and a contact who can approve the order.
- Nameplate photo of the failed compressor and what it was supplying.
- Required flow and minimum pressure at the critical user.
- Air-quality needs: dry, filtered or oil-free.
- Available electrical supply, or whether diesel is preferred.
- Access, space and expected duration of hire.
Frequently asked questions
How quickly can I get a rental compressor in an emergency?
It depends on the machine required, what is available in our fleet at the time, the distance to your site, and how quickly the site can receive and connect it. We do not quote a fixed response time. The fastest results come when you send nameplate photos, the required flow and pressure, and access details in the first call, and have a tie-in point ready.
What size rental compressor do I need if my compressor breaks down?
Size the rental on your actual demand and the minimum pressure at your critical users, not just on the rating of the failed machine. If several compressors share the load, only the shortfall may need covering. Add margin for hose and treatment losses. Our engineers can estimate the duty from your nameplates, running hours and pressure readings before choosing a machine.
Can a diesel portable compressor supply instrument air?
Yes, but only with proper treatment. A portable oil-injected compressor delivers hot, saturated air with some oil carry-over. For instrument or process air it needs an aftercooler, water separator, dryer and suitable filtration to reach the required ISO 8573-1 class. The dew point and filter condition should be checked after commissioning, before the air feeds sensitive users.
What should my plant prepare for emergency compressed air?
Prepare a valved tie-in point on the header, a clear and ventilated position for the machine, a suitable electrical supply if an electric unit will be used, and a named person who can approve the order and arrange gate passes. Plants that depend on air should agree an emergency purchase route in advance so that paperwork does not delay a machine waiting at the gate.
Do you provide operators with emergency rental compressors?
Yes, operators can be provided where the job needs them, particularly for round-the-clock duty or remote sites. On one steel-plant hire, our operators worked 12-hour shifts on a 450 cfm diesel unit running 24 hours a day. For shorter hires, we commission the machine and brief your staff on start-up, shutdown and the safety shutdowns.
Can you repair my failed compressor while the rental runs?
Yes. While temporary air keeps the plant running, our engineers can diagnose the failed machine, identify parts from its make, model and serial number, confirm fit before quoting and carry out the repair or overhaul. This applies to all major brands, since we work as an independent multi-brand specialist rather than an authorised dealer.
Related pages
Technical content reviewed by D. Srinivas Reddy, Managing Partner and service engineer, Reddy Compressors. Last updated 17 October 2026. How our engineering content is reviewed.