Moisture in compressed air lines can turn a good day of sanding, painting, or pneumatic tooling into a mess of rust, water droplets, and wasted air. A refrigerated air dryer is the most direct air-treatment upgrade for a compressor or blower system, but the right choice depends on one number: how much air your compressor actually delivers. The four dryers here cover different compressor sizes, from small shop units up to larger industrial setups. Before you compare extra features, match the dryer to your compressor's output.
Quick take
Match the dryer to the compressor output first. The small-system choices are the Compressor Source dryer and the Schulz ADS 20. The middle option is the Schulz ADS 50 complete kit. The large-system option is the LRSD dryer. Which one makes sense comes down to compressor size and how much control you want. The table below sorts the spend, and the detailed sections below explain the differences that matter.
Price comparison
| Dryer | Price | Airflow | Relative price |
|---|---|---|---|
| LRSD 85 CFM | $980.00 | 85 CFM | |
| Compressor Source 21 CFM | $999.95 | 21 CFM | |
| Schulz ADS 20 | $1,381.80 | 20 CFM @ 100 PSI | |
| Schulz ADS 50 | $1,552.28 | 50 CFM @ 100 PSI |
The bar length reflects the price; a longer bar means a higher price.
Decision matrix
- Small compressor: You can pick between the Compressor Source unit and the Schulz ADS 20. Both are 110V/115V dryers for small systems. The Compressor Source unit carries a higher pressure rating; the ADS 20 includes condenser fan control managed by a temperature probe.
- Mid-size compressor: The Schulz ADS 50 is aimed at this range, and it is sold as a complete kit.
- Large compressor: The LRSD unit is aimed at this larger class, and it is the lowest-priced model in the comparison.
Dryer details
Compressor Source 21 CFM Refrigerated Air Dryer
This dryer is aimed at 5 HP compressors and carries a 232 PSI max working pressure, so it suits a typical small shop air line. It uses R134a refrigerant, includes an automatic timer drain, and has an electronic display that shows dew point and error codes. The 1/2-inch NPT inlet and outlet make hookup straightforward. Choose it when you want a 5 HP-class dryer with a high pressure ceiling and a moderate price. The limitation is that it is built for the 5 HP class, not for larger compressors. If you plan to upgrade to a 10 HP or bigger unit later, this airflow rating will not follow you.
Schulz ADS 20 Refrigerated Compressed Air Dryer
The ADS 20 is the other small-system option in this comparison, rated at 20 CFM at 100 PSI with a 220 PSI max input. It is a non-cycling refrigerated dryer with an electronic controller that displays temperature and dew point, runs the automatic drain on a timer, and uses a temperature probe to control the condenser fan. If you want a dryer that manages more of its own operation for a small compressor, this unit gives you that automated control. The limiting factor is price: it costs $381.85 more than the Compressor Source 21 CFM unit, while its airflow rating is 1 CFM lower. You are paying for the non-cycling control design, not for more capacity.
LRSD 85 CFM Refrigerated Compressed Air Dryer
This LRSD dryer is built for 15 HP and 20 HP compressors and lists an 85 CFM airflow rating. It runs on 110V/60Hz, uses R134a, and has a 1-inch interface for a larger air line. Its specified operating range is 102-145 PSI, and the unit is a non-cycling refrigerated dryer in a 30 x 17 x 32-inch package. The reason to pick it is straightforward: it offers the most airflow in this group at the lowest price, $980.00. The limitation is pressure headroom. At 145 PSI max, it sits well below the 220 PSI and 232 PSI ratings of the two small-system dryers, so it is only a fit if your system pressure stays at or below 145 PSI.
Schulz ADS 50 Refrigerated Compressed Air Dryer Complete Kit
The ADS 50 targets 10 HP and 15 HP compressors and provides 50 CFM at 100 PSI. It is a non-cycling refrigerated dryer with a 200 PSI max input, an electronic controller, automatic drain valve management, and condenser fan control. The complete-kit format is aimed at buyers who need a full middle-capacity package in 115V single phase. Pick this when your compressor sits in the 10-15 HP range and you want a pressure ceiling higher than the 145 PSI LRSD unit. The limiting factor is cost: at $1,552.28, it is the most expensive dryer here, and it costs $572.28 more than the LRSD. You are paying for the 200 PSI input rating and the automated controls, not for the largest airflow number.
Final recommendations
- For a small compressor on a budget, choose the Compressor Source dryer.
- For a small compressor where you want non-cycling operation and automated controls, choose the Schulz ADS 20.
- For a mid-size compressor, choose the Schulz ADS 50.
- For a large system, choose the LRSD refrigerated dryer.
