Alfa Laval Air Cooled Heat Exchangers, Heat Pumps, and Chemical Handling: Answers I Wish I'd Had

I'm a process engineer who has been handling heat exchange and chemical handling orders for 12 years. I've personally made and documented 14 significant mistakes, totaling roughly $230,000 in wasted budget. Now I maintain our team's pre-order checklist so you don't have to repeat my errors.

This FAQ collects the questions I get most often, plus a few I wish I'd asked before my first big failure. If you are trying to understand Alfa Laval air cooled heat exchangers, Alfa Laval chemical handling systems, or just want to answer 'what is a heat pump,' start here.

• What is a heat pump? (and why it is not a Mr. Heater)
• What is an Alfa Laval air cooled heat exchanger?
• How do I size an Alfa Laval air cooled heat exchanger without making a mistake?
• Do I need Alfa Laval chemical handling systems if I already have a heat exchanger?
• Why is pump selection so important in chemical handling?
• Is a heat pump the same as an air cooled heat exchanger?
• Why do people over-rely on brochure numbers? (the Ego snow blower problem)
• What hidden cost delays projects after the equipment arrives?

What is a heat pump?

Put simply, a heat pump moves heat instead of creating it by combustion. It runs a refrigeration cycle; the same cycle can heat in winter and cool in summer. The name confuses a lot of people. It's not a water pump, and it is definitely not the same as a Mr. Heater portable combustion heater.

A Mr. Heater burns propane or kerosene. A heat pump extracts heat from outside air, ground, or process water and rejects it to where you want it. I once had a facility manager tell me his Mr. Heater kept his garage warm, so why not replace a 500-ton industrial heat pump with one? Because a garage heater creates heat, a heat pump moves it. Put another way: if you need direct-fired warmth in a small room, buy a Mr. Heater. If you need efficient climate control for a large process, a heat pump is the better answer.

What is an Alfa Laval air cooled heat exchanger?

An Alfa Laval air cooled heat exchanger rejects process heat to ambient air using finned tubes and fans. It's the equipment you pick when you don't have enough cooling water, or when a cooling tower is too expensive to operate. Air cooled units eliminate drift, makeup water, and chemical treatment of the cooling water side. You also avoid the risk of Legionella in cooling towers. But you gain fan noise and a larger footprint.

When I first started selecting equipment, I assumed air cooled always costs more to run. In humid environments, that's often true. But at a dry desert site, the lifecycle cost can be lower because you skip the water treatment chemistry and tower maintenance. The right answer depends on climate, water cost, and process temperature. Fan maintenance on the air cooled unit is heavy: bearings, belts, VFDs. A cooling tower has its own nasty maintenance. I've learned to compare total lifecycle cost, not first cost.

How do I size an Alfa Laval air cooled heat exchanger without making my mistake?

Use the company's sizing tools, but don't trust them blindly. I assumed the design ambient temperature was the same as the average summer temperature. It is not. In July 2022, we had three days at 104°F, and our new unit was 15% undersized. Production had to be reduced while the process fluid ran too hot.

Now I always use worst-case data from local weather records, not a forecast. Also, check altitude. Air density changes with elevation, and the fan performance changes with it. If you are above 3,000 ft, most standard sizing tables need correction. The same goes for fouling factor: if the process fluid isn't clean, the rating should include it. Oh, and I should add: the hyphenated 'alfa-laval' in our old folders still works for searching, but the current selection tools live on the Alfa Laval website.

Do I need Alfa Laval chemical handling systems if I already have a heat exchanger?

Maybe. Alfa Laval chemical handling systems cover dosing skids, transfer pumps, valves, and controls for chemicals like corrosion inhibitors, biocides, and CIP detergents. If your heat exchanger loop relies on chemical dosing to prevent fouling, then yes—you need both. If your process uses aggressive chemicals, the system also protects your operators and helps you meet compliance.

I made this mistake on a $3,200 order once. Actually, the heat exchanger was $180,000, but the small missing dosing skid was $3,200. I focused on the big equipment and forgot to order the chemical system. The heat exchanger arrived on time; the dosing skid took three more weeks. That's the kind of 'small' oversight that stops a startup. Seriously, plan the chemical handling system as part of the heat transfer system, not as an afterthought.

Why is pump selection so important in chemical handling?

Because 'chemical duty' means more than corrosion-resistant casing. The fluid's viscosity, shear sensitivity, solids content, and required pressure all determine the pump type. For shear-sensitive polymer emulsions, a twin screw pump can be a much better choice than a gear pump. For simple transfer of thin acids, a centrifugal pump might be enough. For precise dosing, a diaphragm pump is often the answer.

I learned this after a communication failure: I said 'positive displacement pump' and the vendor heard 'gear pump.' We were using the same words but meaning different things. The unit arrived and the fluid came out churned and degraded. That cost $890 in rework and a week of delay. Now I specify pump type plus viscosity range and allowable shear rate, and I never assume the vendor will ask. I also list seal material, because standard seals can fail fast with solvents.

Is a heat pump the same as an Alfa Laval air cooled heat exchanger?

No. A heat exchanger transfers heat from one fluid to another without changing the temperature level. An Alfa Laval air cooled heat exchanger rejects heat from a process stream to ambient air. A heat pump uses a refrigeration cycle to move heat from a low temperature source to a higher temperature sink. They solve different problems.

Sometimes specs ask for a heat pump when the real need is process cooling. That confusion caused a project to go over budget by $30,000. Before you call it either, answer this: do you want to chase a temperature difference, or do you want to lift the heat to a higher temperature for reuse? If it's the first, you need a heat exchanger. If it's the second, you need a heat pump. Many industrial sites use both: a heat pump recovers waste heat, and an air cooled heat exchanger dumps excess heat when the heat pump can't use it.

Why do people over-rely on brochure numbers? (the Ego snow blower problem)

Equipment selection from a nameplate is like buying an Ego snow blower because it says 56V and 18 inches of clearance. Then lake-effect snow arrives, the battery gets cold, and the unit stalls on wet heavy snow. The spec says it can handle snow; it doesn't tell you what kind, at what temperature, or for how long.

Industrial ratings work the same way. A heat exchanger rated for 1,000 kW at 'standard conditions' may not achieve that with your fouled fluid, your altitude, and your fan placement. I now ask vendors for performance curves at the actual operating point, not just the brochure rating. That simple habit caught 11 potential mismatches in the last 18 months. Also check electrical supply: voltage drops over long cable runs reduce motor output, which cuts airflow.

What hidden cost delays projects after the equipment arrives?

Documentation. The equipment can be perfect, but if the submittal package doesn't match the insurance requirements or the local code, the inspector rejects it. After the third rejection in Q1 2024, I created our pre-shipment checklist. Now we verify every drawing, material certificate, and test report before the truck leaves the factory. In one case, the missing document was a stamped drawing from a licensed engineer; that alone caused $4,000 in rework and a 9-day delay.

Also, don't say 'as soon as possible' when you ask for delivery. I said it once and the vendor heard 'whenever convenient.' Now I use exact dates. Switching to a shared tracking spreadsheet cut our average order turnaround from five days to two days. Digital efficiency matters, but it starts with clear communication.

Per FTC guidelines, performance claims need substantiation. If a vendor claims 'corrosion resistant' or 'low maintenance,' ask for the test report, not just a brochure sentence. That applies to heat exchangers, heat pumps, and pumps alike.