Thermopy Guide
Split vs VRF vs chiller — what to choose
Compare capital cost, SEER/EER and running cost for common commercial and large-home cooling options.
System types at a glance
Split systems suit small/medium spaces. VRF scales across zones with heat recovery. Chillers serve large commercial loads with central plant.
Compare with numbers
Use Cooling Comparison to model SEER, part-load behavior and local tariffs instead of relying on rule-of-thumb charts alone.
Start with cooling load, not equipment catalogues
Size or compare systems only after you know peak and seasonal cooling load. Oversized plant cycles poorly; undersized plant runs flat-out and still misses setpoint. Use room or building load as the common baseline for split, VRF and chiller options.
SEER vs EER — what each number means
EER is efficiency at a single rated condition; SEER weights part-load performance over a cooling season. For annual cost, SEER (or seasonal metrics in your region) usually matters more than peak EER — especially where most hours are not at design load.
Maintenance and refrigerant realities
Filter cleaning, coil access, leak checks and refrigerant type all affect lifetime cost and downtime. Distributed splits mean many outdoor units to service; VRF and chillers concentrate complexity but need skilled maintenance and clear refrigerant management.
Total cost of ownership over a realistic horizon
Compare 10–15 year TCO: capital cost, electricity at your tariff, maintenance contracts and expected component replacements. A higher-SEER VRF can beat cheap splits on TCO in multi-zone buildings even when first cost looks worse.
When VRF beats split — and when a chiller wins
Choose multi-split or VRF when you have many zones, long pipe runs and simultaneous heating/cooling needs. Prefer chillers for large floor plates, central plant rooms and sites with existing hydronic distribution or a facilities team ready for water-side systems.
Run the numbers in Cooling Comparison
Use Thermopy Cooling Comparison to model SEER/EER, part-load behaviour and local electricity tariffs side by side. Export the comparison before you lock a specification or contractor quote.
Get exact numbers with our free calculator
Use your room data, climate and energy rates to generate actionable results in minutes.
Open calculatorFAQ
Is VRF always better than split?
Not for single small rooms — VRF shines with multiple zones and simultaneous heating/cooling needs.
What SEER should I target?
Higher SEER reduces running cost but raises capex; compare 10-year total cost, not sticker efficiency alone.
When is a chiller justified?
Large floor plates, central plant maintenance teams and high simultaneous load often favor chillers.
When is heat recovery VRF worth the premium?
When zones simultaneously need heating and cooling — for example perimeter vs core, or mixed-use floors. Heat recovery can move energy between zones and cut net electricity versus separate heating and cooling plant.
How should I think about outdoor unit noise?
Check sound power/pressure data at the setback distances that matter for neighbours and bedrooms. Multiple split condensers can be noisier at the façade than one carefully located VRF outdoor unit or a remote chiller plant — plan acoustic setbacks early.