Heat Exchanger & Refrigeration Maintenance Checklist: 7 Steps Before You Call Emergency Service

When to Use This Checklist

I've been doing emergency industrial maintenance for 12 years. Over 500 rush calls since 2013—or close to 500, I'd have to pull the work order system to be sure. Everything from a 2 AM ice machine breakdown to a pool heater that had to be running before a weekend event. This checklist is the 7-step sequence we actually run through when a service call comes in. Follow it, and there's a decent chance you'll catch the problem yourself and skip the emergency callout fee.

It applies when you're dealing with:

• Plate heat exchanger losing pressure or temperature efficiency
• Ice machine producing less ice or cloudy ice
• Pool heater not reaching set temperature
• Air-cooled condenser running hot or cycling frequently

Seven steps, roughly 45 minutes if you do it properly. It surfaces the root cause in about 80% of the calls we get.

Step 1: Isolate the Equipment and Check the Obvious First

Don't touch anything yet. Every heat exchanger or refrigeration unit has a feed side and a discharge side. Close the incoming isolation valve first, then the outlet. Drain if possible. You don't want to crack a gasket on a pressurized exchanger and get 5 gallons per minute of hot water or refrigerant spraying across the room.

Once the unit is isolated, check these before anything else:

• Electrical—breaker tripped? Control panel showing a fault?
• Gauges—pressure and temperature sensors. Can you trust the readings?
• Unusual noise—buzzing, clicking, grinding from the pump or compressor?

This step sounds basic. But about three out of ten emergency calls I've been on ended right here. Someone forgot to reset a breaker. A temperature sensor was reading 10 degrees off and the whole system was compensating for bad data.

Step 2: Inspect the Gaskets and Plates

If you're running a plate heat exchanger, gaskets are suspect number one. The rubber seals between plates degrade faster than most people expect—typically 3 to 5 years depending on service conditions, sometimes sooner if you're running aggressive chemicals or temperature swings.

Here's how to check:

1. Tighten the compression bolts and open the frame slowly. Count your plates.
2. Look at each gasket for cracking, hardening, glazing, or any deformation.
3. Check the plate surfaces in good light—look for leakage trails, especially near the gasket grooves.

Alfa Laval heat exchanger gaskets come in different materials depending on your media—NBR, EPDM, FKM. If you're replacing standard water-to-water units, NBR is usually fine. If you're running steam or chemical process fluids, go EPDM or FKM. Don't try to save money here.

Honest talk on cost: Alfa Laval's OEM gaskets run a wide range depending on model and material. I don't have their full 2025 price sheet in front of me, but from the purchase orders I've processed over the last two years, a single gasket for an M10 series unit typically lands somewhere between $15 and $45. Aftermarket options are 30–50% cheaper, but they don't always fit as precisely. For high-cycle applications where you're opening the unit regularly, OEM pays for itself.

Step 3: Clean the Coils and Cooling Surfaces

Air-cooled condenser and evaporator coils need cleaning every few months with compressed air or a soft brush. Quarterly minimum if you're in a dusty environment.

We use a portable blower—the DeWalt blower with the 20V battery works well for this because the extension nozzle lets you reach into tight coil sections, but any blower with a long nozzle will do. The key is to blow with the fin direction, not against it. Blowing against the fins flattens them, and flattened fins don't give you the surface area you need.

If the fins are greasy or dirty beyond what air can handle, use a coil cleaner and rinse with low-pressure water. Not a pressure washer. Low pressure only. A garden hose with a soft brush works better than a pressure washer that destroys your fins. Ask me how I know.

Step 4: Check the Refrigerant Cycle (and How to Clean an Ice Machine While You're At It)

If you're dealing with an industrial ice machine or any refrigeration unit, check the refrigerant. Low suction pressure could mean low charge or a restriction. Those two look identical on a gauge but have completely different fixes. You'll need a pressure drop test to tell them apart.

For how to clean an ice machine, here's the process that works when you're seeing reduced production or cloudy ice:

1. Shut off the water supply and power.
2. Empty the bin and let the system warm to room temperature—about 20 minutes.
3. Remove the water curtain and wash the evaporator surface and lines with an ice machine cleaner solution and a soft cloth.
4. Rinse thoroughly with clean water until the water runs clear.
5. Reassemble, turn the water back on, and run two full cycles before harvesting ice.

Don't use dish soap or any solvent-based cleaner. They strip the plating off the evaporator, and once that plating is gone, ice sticks to the surface and you'll never get a clean release again.

The industry guidance says commercial ice machines should be deep-cleaned at least every six months; more often if you're on hard water (source: general industry maintenance guidelines). I wouldn't call that a hard rule, but every six months keeps you out of trouble.

Step 5: Test the Heater Side

If it's a pool heater or any process heating application, check these:

• Heater inlet and outlet temperature differential—if it's not 5–8°F, something's wrong with flow or the heating element
• Scale buildup—pool heater exchangers foul internally and lose efficiency fast
• Ignition and gas pressure if it's a gas-fired unit

I'll be upfront: this isn't my deepest area of expertise. If it's a refrigerant-side issue, I'll hand it to a refrigeration tech. But for flow, scale, or mechanical faults, a general maintenance person can handle it. Pool heaters scaling internally—calcium blocking the tubes—is the most common silent failure I see. Most people don't notice until the heater just stops working.

Step 6: Order the Right Parts (Don't Guess the Price)

Once you've confirmed what needs replacing, verify before ordering:

• OEM part number—photograph the nameplate
• Gasket material compatibility with your media
• Lead time—if you need it fast, some suppliers can overnight it for a premium

On Alfa Laval heat exchanger price: as of Q1 2025, a mid-size plate heat exchanger (think M6 or M10 series, depending on plate count and plate material) runs somewhere between $1,800 and $9,500. That's based on dealer quotes our team has processed over the past six months. Verify current pricing yourself before committing—copper, nickel, and stainless costs fluctuate and that flows straight through. If you're looking at specialty plate materials like titanium or high-pressure ratings, expect that number to go higher.

Here's the honest part: if you're only running occasional duty (low-pressure pool heating or small chillers), the Alfa Laval premium isn't worth it. But if you're running continuous duty, corrosive media, or need tight sealing performance, the extra spend buys you reliability. For 80% of cases, either works. Know which side you're on before you buy.

Step 7: Pressure Test and Put It Back in Service

Before you put the unit back in service:

1. Water side: pressure test at 1.25x working pressure. Hold for at least 30 minutes.
2. Refrigerant side: check static pressure, then run the system for 15 minutes with normal superheat and subcool readings.
3. Reopen isolation valves downstream-first. Not upstream-first.
4. Monitor temperature and pressure for 30 minutes. If everything is stable after 30 minutes, you're good.

Log your readings. Next time something goes wrong, having a baseline with normal values makes the difference obvious.

Common Mistakes That Cost You a Second Service Call

• Overtightening the compression bolts. The gasket needs even compression, not crushing. Tighten in a diagonal pattern, two to three passes to the torque spec. I've seen more return calls from this than any other cause.
• Skipping the cleaning step. Replacing parts without cleaning coils means you'll be calling again in three months.
• Using a generic gasket instead of OEM. It looks like a shortcut when you're in a hurry. It's not. Generic gaskets age faster and often leak after the system heats up.
• Not running a pressure test. I learned this the hard way. Skipped it once after a rebuild because everything looked fine. Four hours later, a leaking seal cost us $800 in after-hours labor to redo the job. I haven't skipped a pressure test since.

One more thing—if you get to Step 4 and the refrigerant pressures are off but you can't find why, don't improvise. Call a qualified refrigeration technician. More often than not, the "I'll just top it off" approach ends up costing three times more than the original repair would have.