Two dryer quotes can look like a straightforward price comparison until you discover that one includes filtration and installation while the other covers only the dryer. The differences become more expensive after the purchase, when your team has to supply the missing pieces.
If you are comparing a refrigerated vs. desiccant air dryer for a Los Angeles facility, begin with the duty each supplier has agreed to meet. Then compare the complete package. At American Compressor, we help customers size, supply and service Kaeser dryers around their operating conditions.
Our compressed air treatment guide explains how filters, drying and condensate management work together. This checklist focuses on the purchasing decision: what should be written into the quote before you approve it.
Put the required dryness in writing
A refrigerated dryer cools compressed air so water can condense and be removed. A desiccant dryer uses an adsorbent material to remove water vapor and can achieve much lower pressure dew points. Kaeser’s dryer-selection guidance describes both methods.
Pressure dew point is the temperature at which water vapor begins condensing at the stated pressure. Your process requirement and the coldest conditions the air will encounter help determine the target. Ask the supplier to state the required dew point and the operating conditions under which the proposed equipment will deliver it.
Do not accept a comparison in which one supplier quotes general plant-air drying and another assumes a much lower dew point. Resolve that difference first. If a particular process sets the requirement, attach its specification to both requests for quotation.
Check the conditions behind the flow rating
A catalog flow rating is useful only alongside its reference conditions. The air reaching your dryer may be hotter, at a different pressure or subject to different ambient temperatures. Those differences can change the capacity you need.
Give each supplier the same information: maximum expected airflow, operating pressure, inlet temperature, ambient conditions and working schedule. Ask which correction factors were applied and what margin remains at the demanding end of that range. Kaeser’s air-treatment guidance specifically warns that temperature changes can reduce effective dryer capacity.
Also explain any planned expansion. A possible future machine is different from an approved production line arriving in three months. Pricing a defined future requirement makes the capacity decision easier to evaluate.
Compare operating costs on the same basis
The purchase price does not tell you what the dryer will cost over your actual operating hours. Request the electrical demand, control arrangement, service needs and expected consumables for the proposed model.
For a regenerative desiccant dryer, ask how regeneration is powered and whether it consumes compressed purge air. Heatless, heated and blower-purge designs have different arrangements. Kaeser’s desiccant range includes these alternatives, so a generic allowance for desiccant operation is not enough.
Use your own operating hours and electricity tariff for cost estimates. Ask the supplier to identify assumptions about loading and control behavior. A comparison based on continuous full production may give the wrong answer for a shop with substantial idle periods.
Make the installation boundary clear
Ask for a written list of included equipment and work. Depending on the design, that may cover filters, drains, bypass piping, isolation valves, electrical connections, controls and commissioning. Identify who provides each item and who coordinates access to the compressor room.
Confirm the filtration arrangement for the selected dryer with its manufacturer’s instructions. A filter listed as an optional extra in one proposal may be necessary for the complete application. Our Kaeser filter range can be considered alongside dryer selection rather than as an afterthought.
Check physical access as well. Delivery routes, service clearance and the position of existing pipework can affect installation. Ask whether removal of the old dryer and any temporary air arrangement are included.
Agree on acceptance and service before ordering
Decide what will be checked at handover. The agreement should identify the operating conditions, measurements and documentation needed to confirm that the installed system meets the specification. A running indicator alone does not prove that the required dryness is reaching the process.
Name the person responsible for reviewing those results. Keep the equipment settings, manuals and commissioning record accessible to maintenance. Ask which service tasks are required, what access they need and how the supplier handles parts or troubleshooting.
Before you approve the order, put the two quotes side by side and mark every difference in duty, scope and assumptions. Then request clarification on the gaps. That creates a much fairer comparison than choosing from the headline price.
Frequently asked questions
Is a desiccant dryer always the better purchase?
No. The required dryness, environment and process determine whether its lower dew point is needed. Compare equipment that meets the same written duty.
Can I size a dryer from compressor horsepower alone?
No. Use airflow, pressure, temperature and the required dew point. Have the supplier confirm capacity at your actual inlet and ambient conditions.
Should installation and filters be included in the quote?
The quote should state clearly what is included and who supplies the remaining items. Compare complete installed scopes, including the filtration the selected design requires.
Discuss your dryer requirement with our team
We supply and support Kaeser refrigerated and desiccant dryers for Southern California facilities. Review our Kaeser dryer range and contact American Compressor with your airflow, pressure, temperatures and required dew point. We can help you turn those details into a clear equipment and installation discussion.
