Retrofit or replace? Comparing refrigeration options with your own operating data

Has your heat load changed?

A system that worked well ten years ago may now face more product, warmer intake, more door cycles or higher ambient temperatures. Before comparing equipment, reconcile today's load drivers with the original design: product type and tonnage, intake temperature, room volumes, door activity and design ambient. If original design data is missing, ask an engineer to estimate the load and state assumptions.

Comparison table

Criterion	Evidence from your records	Ask bidders for
Capacity	Pull-down curves, run hours, excursions at peak	Capacity at stated design conditions
Energy	kWh per tonne trend, peak demand	Expected energy at your operating profile, with method
Refrigerant	Type, charge, leak and top-up history	Compliance with local rules and future availability
Maintenance	Breakdowns, parts lead times, cost per year	Service plan, spares, local response
Safety	Machine room condition, detection, inspections	Compliance with applicable safety standards and codes
Disruption	Demand windows	Installation plan and downtime
Lifecycle cost	Your energy tariff, labour, losses	Capex, maintenance and expected life on the same horizon

Why refrigerant rules matter

Many countries are reducing high-GWP refrigerants under the Kigali Amendment to the Montreal Protocol; in the EU, Regulation 2024/573 sets service and placing-on-market restrictions. A retrofit that keeps a restricted refrigerant may face rising service costs or availability limits. Check the rules that apply at your site; they differ by country and equipment type.

Lifecycle comparison you can run

Lifecycle cost (per option) = capex + Σ over N years (annual energy cost + maintenance + expected repair + refrigerant service) − residual value. Use the same N, the same tariff and the same operating profile for both options. Do not add avoided-loss benefits unless you can trace them to your spoilage records.

Hypothetical, method only: option A (retrofit) capex 100, annual running 40; option B (replace) capex 220, annual running 28; over 10 years A = 500 and B = 500. Equal totals mean the decision turns on risk, refrigerant compliance and disruption — not on the arithmetic.

What if you lack energy or maintenance data?

Install temporary metering on the refrigeration supply for several weeks and rebuild a maintenance log from invoices. Mark all derived figures as estimates and ask bidders to use the same values.

Checklist

• Current heat load reconciled with original design
• Refrigerant type, charge and leak history documented
• Breakdown and parts history summarised
• Safety inspection status known
• Both options quoted on the same basis
• Lifecycle comparison on the same horizon and tariff

Storage conditions depend on product, site and local law. No option should be presented as guaranteeing savings.