If water in your air lines is causing tools to rust or spray guns to sputter, you've reached the point where a refrigerated air dryer makes sense. For a 5 HP compressor setup, there are two solid routes in the air treatment aisle: the Compressor Source 21 CFM Refrigerated Air Dryer and the Schulz ADS 20 Refrigerated Compressed Air Dryer. One is more affordable and rates a little higher on airflow; the other is a more controlled, compact non-cycling unit. This comparison walks through the differences so you can pick the right one for your shop.
Quick verdict
Both dryers remove moisture from compressed air using refrigeration and are built for 5 HP compressors. The Compressor Source unit is the lower-priced pick, with a bit more rated airflow. The Schulz ADS 20 is the more feature-rich option, with a non-cycling design, digital temperature and dew point display, condenser fan regulation, and a quick-disconnect automatic drain. Choose Compressor Source if budget and airflow are your main priorities; choose Schulz if you want the more sophisticated controller and a dryer that actively manages its fan speed.
At a glance
| Feature | Compressor Source 21 CFM | Schulz ADS 20 |
|---|---|---|
| Price | $999.95 [#######---] | $1,381.80 [##########] |
| Intended compressor | 5 HP | 5 HP |
| Rated airflow | 21 CFM | 20 CFM @ 100 PSI |
| Max pressure | 232 PSI | 220 PSI |
| Refrigeration design | Refrigerated with R134a | Non-cycling refrigerated |
| Controls | Electronic dew point display and error codes | Digital temp and dew point display, timed automatic drain, condenser fan probe |
| Drain | Automatic timer drain | Automatic timer drain with quick-disconnect |
| Country of origin | China | Italy |
Where each product wins
The Compressor Source is the better match when your priority is the lower price and a bit more airflow. The Schulz is the better match when you want a more involved controller and faster drain access. Your choice comes down to whether capacity and cost matter more, or control and convenience.
Product notes
21 CFM Compressed Air Refrigerated Air Dryer for 5 HP Air Compressors 110V
This Compressor Source dryer is the lower-priced of the two, with a rated airflow of 21 CFM, a maximum working pressure of 232 PSI, and a 1/2" NPT inlet and outlet. It uses R134a refrigerant and comes with an automatic timer drain plus an electronic display that shows dew point and error codes. The straightforward control set covers the essentials and will feel familiar to most compressor owners. The trade-off is that you don't get the condenser fan management or quick-disconnect drain that the Schulz ADS 20 includes. If you're comfortable with the simpler design, this is a strong pick for a 5 HP compressor.
Schulz ADS 20 Refrigerated Compressed Air Dryer - 20 CFM, 115V
The ADS 20 is the higher-priced dryer in this comparison, and it brings a non-cycling refrigerated design rated at 20 CFM @ 100 PSI with a 220 PSI maximum input. The electronic controller handles more of the work: it displays temperature and dew point, operates the automatic drain on a timer, and adjusts the condenser fan using a temperature probe. The compact construction and quick-disconnect drain make installation and maintenance more convenient, and the unit is made in Italy. The trade-off: you pay more and you get a little less rated airflow than the Compressor Source, so the higher price goes toward control features and a drainage setup rather than capacity.
Final choice by use case
Go with the Compressor Source 21 CFM Refrigerated Air Dryer if you want to keep your spend down and have a little extra airflow headroom. It handles the basics well and leaves more money in your pocket.
Go with the Schulz ADS 20 if you're ready to pay more for a dryer that gives you more control and a more convenient drain setup. That higher price buys a unit that does more managing for you and is easier to service.
