Set up the loop mechanically first, prove leak-free circulation and sufficient chiller flow second, then enable refrigeration and log the first full cooldown.
Before equipment arrives
Confirm that the filled tub weight is supported, the floor can get wet, drainage is practical and the chiller has the ventilation clearance required by its manual. Keep electrical connections protected from splash and use local-code GFCI/RCD protection.
Lay out the hydraulic loop
Baseline loop. UV, ozone, bypasses and heaters change placement; always follow the equipment manufacturer’s required orientation and electrical instructions.
Keep suction runs short and unrestricted. Use unions and isolation valves around the filter and chiller. Avoid stacking unnecessary 90-degree elbows where a sweep or better routing can be used.
Prime and leak-test
Fill the tub, open all isolation valves and prime the pump according to its manual. Run circulation without refrigeration first. Check every joint dry-to-wet, purge trapped air, confirm stable return flow and inspect the filter housing for correct sealing.
Verify flow before refrigeration
The chiller’s minimum flow is a hard gate. If you can measure return flow, do it. Otherwise use the pump curve and a conservative system-resistance model. A new clean filter is the easiest condition; leave margin for fouling.
Commission the thermal side
Record starting temperature, ambient temperature, exposure and time. Let the system cool continuously to target while checking for abnormal cycling, icing, pump noise or flow decline. The first pull-down becomes the benchmark for later troubleshooting.
Save a baseline
Write down flow, clean-filter pressure if available, cooldown time and normal chiller duty cycle. When performance later changes, compare against the baseline before replacing parts.
Frequently asked questions
Should the filter go before or after the chiller?
A common baseline is pump → filter → chiller so the heat exchanger receives filtered water, but the exact manufacturer instructions take priority.
Can I run the chiller before all air is purged?
Do not intentionally run refrigeration with an unstable or air-bound loop. Establish reliable circulation first.
Do I need to measure flow?
A measured flow rate is best. If you cannot measure it, use a conservative pump-curve model and leave margin above the minimum required by the chiller.
Sources & data references
What to read next
Run your exact setup
Use your real tub volume, temperature target, climate, pump, filter and plumbing. ChillSizer checks thermal capacity and actual modeled flow together.
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