Frequently Asked Questions

Buying New Equipment

What is CFM and what is the difference between CFM FAD or displacement CFM?

Here at Algar Air we measure the amount of air provided by your Air Compressor in CFM which stands for Cubic Feet per Minute. This is most important information when buying a new compressor or wishing to add to the system for 2 reasons. Firstly, and most obviously, you need to know the total consumption of the equipment that will be using cfm so you can size you compressor correctly. Secondly, if you are buying a Piston Compressor, manufacturers supply two sets of data for CFM; a displacement figure which is what is produced at the pump but the one you need is the FAD (free air delivered) which what you actually get at the outlet. It is important to make sure that when buying a piston compressor that you get this FAD figure as that is what you need to match to your consumption.

Can I add to my compressed air set-up?

That depends on your current consumption. Usually when we size a compressor we suggest a unit slightly larger than required (futureproof so that you do have some room for expansion of your business without having to replace the compressor so that then yes you can expand (within reason). The best thing to do is to add up the current consumption in cfm (cubic feet per minute) then find out the amount of cfm the new equipment will use and compare this to the output of the compressor. Always bear in mind bar pressure required as this affects the amount of cfm produced – the higher the bar required the lower the cfm.

What size Air Compressor do I need?

The best way to determine what size compressor you need is to add up the consumption of each piece of equipment using air. Ideally collate the information in the same measurement format. We predominantly use cfm (cubic feet per minute). Once you have this information a good ‘rule of thumb’ is divide the cfm by 4 to get the HP then to work out the kw take the HP x4 then divide by 3. There are limitations to this calculation though so when ordering a Compressor always give the cfm you need as the higher the bar pressure the lower the cfm that compressor will produce. In many cases this is difficult to ascertain so call on one of our experienced engineers for some advice on 0114 2432347

H&S Info

HSE have just visited; can you help me understand what they need from me?

Yes, we are experts in the legislation surrounding Compressed Air Systems; just give us a call on 0114 2432347 to discuss. We will action whatever you need to comply immediately.

Can I have the material safety data sheets for any oil I buy?

Yes available on request.

Can I have a Risk Assessment & Method Statement for any work you carry out?

Yes we provide RAMS for all works.

Prices & Payment Methods

How can I pay?

We accept various methods of payment. If you request a quotation from us then it will state on the relevant payment terms for you. In all other cases payment is due on order for parts or on completion for call outs.

  • Credit Account – Download form – (usually takes a few days to set-up.)
  • Credit or Debit Card in person at our offices (incurs a 2% charge).
  • Cheque.
  • FPS or BACS Online Banking payment to the following details:
    • Bank: Yorkshire Bank plc
    • Bank Acct Name: G,SP,PA Algar & S Kidd T/A Algar Air
    • Sort Code: 050868
    • Acct No: 33271697
    • IBAN: GB86YORK0508683327197
    • BIC:YORKGB21868

Is there a re-stocking fee?

Yes, if you buy a part from us that isn’t faulty most manufacturers charge us 20% re-stocking fee as a guide.

What is the Labour Rate?

We charge £38.50 per hour (minimum 1 hour and then 15 minute increments thereafter) Discounted Labour rates available for Service Contracts.

Is there a call out fee?

No we do not charge a call out fee. We pride ourselves on been a quality affordable service and this is part of our commitment to this.

Servicing/Using your Air Compressor

What do I do with waste water?

Well let’s look at what the waste water is; Compressed air holds a lot of water vapour, and once that vapour becomes cooled into a liquid (condensate) what’s created is a dirty, oily watery mixture that can’t simply be sent down the drain and is regulated under the 1991 Water Resources Act.

Since the condensate is approximately 95% water and 5% oil, condensate management systems (oil/water separators) have been developed to reduce or eliminate the amount of oil in the condensate. Once the water has been through the separator it should be then piped into the foul sewage system.

What weekly checks should I be doing on my compressed air system?

We recommend the following:

  • Drain the air tank/receiver/vessel,
  • Check any autodrains are working correctly,
  • Check/clean out any external panel filters,
  • Check for any air leaks on pipework,
  • Check for oil leaks on hoses,
  • Check oil level in compressor.

Why is there a service schedule on my compressor?

It’s preventative maintenance. Your compressor needs servicing regularly to help prevent downtime. Consider this if your Compressor wasn’t working what would be the consequences? No production possibly? How much would this cost your business for every hour of non-production? Keeping a good service schedule means the service items are changed regularly and so less likely to fail. Plus any potential faults can be identified and remedied without every getting to the breakdown stage.

When can I have a service engineer?

For breakdowns and repairs, as our motto states ‘Your pressure is our Priority’ so we do everything possible to get an engineer to you asap. We have a call out engineer that only take on light jobs or just call outs that day so we can get someone to you as quickly as possible. We have also recently implemented a new system that let’s us speak to the service engineer while you are on phone so we can tell you when you are on the initial call an accurate time scale. Call our breakdown team on 0114 2432347 day or night.

For servicing, we organise the parts for you then contact you to arrange a mutually agreeable time to carry out the work. We may have the parts in stock but if not most kits are available to us 2-3 days delivery.


How do I turn off my compressor correctly?

All compressors are different so check out your manual for best practices however you can always get an engineer to show you when they are in servicing. Two things you mustn’t do is regularly stop the compressor using the emergency stop button or the isolator as overtime this will damage the compressor.

Why does my compressor struggle to start when it’s cold?

There are a couple of reasons that this maybe happening. One reason is that compressors generally don’t like cold weather. The oil changes viscosity the colder it gets and makes it harder for the oil to lubricate the machine. Refrigerant dryer is frozen up. If your compressor house gets very cold in the winter we can help by installing a heater to take off the chill. If you are interested in this service contact us now.

Why have I got water in my system?

The compressed air leaving the compressor is normally around 65-75C which contains a lot of water vapour and once that comes into contact with pipework/air tanks etc it cools rapidly and turns back into a liquid water. To dry the air we would install a refrigerant dryer and filters to remove the majority of the water from the compressed air.

If you already have a refrigerant dryer and filters it worth checking whether it’s switched on! I know obvious but it’s amazing how many call outs we’ve been to where this has been the case. Otherwise the filters need checking for blockages and/or the gas in the fridge maybe low. Either way you can call our refrigerant engineer to come and have a look for you.