What is generator heat exchanger descaling and why is it necessary?

Heat exchanger descaling removes mineral deposits, salt buildup, and marine growth that restrict water flow. Regular descaling helps prevent generator overheating, improves cooling efficiency, and extends the life of the heat exchanger and generator.

What are the signs that my generator heat exchanger needs descaling?

Common symptoms include high generator temperature, reduced water discharge, frequent alarms, or automatic shutdowns. These issues often indicate restricted cooling passages caused by scale or debris.

How often should generator heat exchangers be descaled?

Follow the generator maker's service schedule. Warm salt water and long running hours build scale faster, so a slowly rising operating temperature or weaker water flow at the exhaust is a sign it is due.

What does your heat exchanger descaling service include?

Our service includes isolating the cooling circuit, circulating marine-safe descaling solution, flushing the system thoroughly, inspecting zinc anodes, and verifying proper cooling flow after service.

Is descaling safe for my generator and cooling system?

Yes. We bypass the raw water impeller so it stays out of the cleaning circuit, circulate a biodegradable marine descaler (Barnacle Buster) made to dissolve scale without harming copper, bronze or rubber, and then flush the system with fresh water. On an old heat exchanger, removing scale can expose pinholes the scale was hiding; if we find any, we show you before going further.

Can descaling improve generator performance and reliability?

Yes, when scale is the problem. Proper cooling reduces engine stress, keeps the operating temperature steady and prevents overheat shutdowns caused by scale during extended use.

Do you inspect other cooling components during descaling?

Yes. We also check raw water flow, hoses, clamps and zinc anodes, and recommend an impeller replacement if needed. We tell you what we found and what we recommend, and nothing extra is done without your OK.

Marine technician connecting clear hoses from a descaling pump system to the raw water intake

Marine technician connecting clear hoses from a descaling pump system to the raw water intake (2)

Generator Heat Exchanger Descaling

If your generator runs for 20 minutes and then shuts down with an overheat code, and the impeller and strainer are fine, the heat exchanger may be clogged with scale. We perform an acid-flush descaling to dissolve calcium buildup and bring back cooling capacity without removing the unit.

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$150 /hr

Labor estimate Usually 4–8 hours

Book sends us a ticket; nothing is charged online. Before any work you get a written estimate for labor, parts and the trip fee, and nothing is done without your OK.

Trip fee By distance, one way: $30 in San Pedro, $50 in Long Beach

San Pedro$30
Wilmington, Terminal Island$40
Long Beach: Shoreline, Rainbow Harbor$50
Long Beach Marina, Alamitos Bay$60
Redondo Beach$60
Seal Beach, Huntington Harbour$75
Marina del Rey$85
Newport Beach$110

Farther away: $25 plus $2.50 a mile, one way from our San Pedro shop. No trip fee when the boat comes to our shop, or for plan members. The work of a visit is at least $150; the trip fee is on top.

Registered in California: Breeze Marine Boat Service LLC, San Pedro
Where we work: At your slip from Marina del Rey to Newport Beach, or in our San Pedro shop
Questions first: (213) 693-0224 or submit a ticket

About this service

Restore Cooling Efficiency

Stop the
Overheating.

If your generator shuts down under load, scale in the heat exchanger is a common cause. Descaling often restores heat transfer without expensive part replacement.

The "Invisible" Blockage

Over time, calcium and minerals from seawater build up inside the heat exchanger tubes, insulating them and preventing proper cooling - a common cause of marine generator overheating.

Circulation Flush

We use a circulation pump to move a biodegradable descaling solution (Barnacle Buster) through the raw water cooling system, dissolving the scale over a few hours.

Cost Effective

Replacing a heat exchanger is expensive. Descaling often brings back much of the lost cooling capacity for a fraction of the price.

The Descaling Process.

Careful, minimally invasive generator heat exchanger cleaning.

Bypass

We close the seacock and bypass the raw water impeller, keeping it out of the cleaning circuit.

Circulate

We connect our pump system and circulate the descaling agent for 2-4 hours, monitoring the fluid color for reaction.

Flush

Once the reaction stops, we flush the entire system with fresh water to remove all chemical residue and dissolved calcium.

Verify

We install a new zinc anode and run the generator under full load to confirm temperatures hold steady.

Results You Can See.

Restoring flow and lowering operating temperatures.

Heat exchanger descaling setup in a yacht engine room

Descaling pump hoses connected to a generator heat exchanger

Heat exchanger tubes clear after the scale was dissolved

Safe for Your System.

We use industry-standard solutions compatible with marine metals.

Biodegradable Barnacle Buster Descaler

Non-Corrosive Safe for Copper/Bronze/Rubber

No Removal Service Done In-Place

Common Questions

Will this damage my engine?

It should not. The descaler is made to dissolve scale, not metal or seals, and we bypass the impeller. On an old heat exchanger, though, removing scale can expose pinholes the scale was hiding; if we find any, we show you before going further.

How do I know if I need this?

If your impeller is new and the strainer is clean, but the generator still overheats after 15-30 minutes of use, you likely have scale buildup.

Keep Your AC Running.

Solve the overheating mystery. Schedule a heat exchanger flush.

Descale My Generator

Descaling and Marine Generator Maintenance

Scale builds slowly, so a generator that ran cool last season can start overheating this season without any single part breaking. Adding a descaling check to regular marine generator maintenance, alongside the impeller and strainer, keeps seawater moving freely through the cooling side.

Whenever a generator goes in for marine generator service, mention any rising temperatures or overheat shutdowns, since scale in the heat exchanger is a common cause.