Domestic HVAC Regassing Costs & Guide

Scope of Works

• Initial checks – confirm refrigerant type (R-32, R-410A, etc.), inspect for obvious leaks or oil stains, and make sure any F-Gas records are up to date.

• Recover old gas into a certified cylinder for recycling or safe disposal.

• Pressure-test & leak search – nitrogen test and electronic sniffer; repair or re-flare any joints that fail.

• Deep vacuum – pull the system down to ≤ 500 microns to remove air and moisture.

• Recharge – weigh in the exact charge of new refrigerant using calibrated digital scales.

• Commission & log – run the unit in cooling (and heating if it’s a heat-pump), fine-tune superheat/sub-cool, complete the F-Gas service log and attach a new charge label.

• Clean-up – reinstate trunking or loft insulation, tidy the work area and brief the customer on basic checks between services.

Typical Cost (incl. VAT, 2025)

Time on Site

• 1 – 2 hours for a straightforward top-up when no leaks are present.

• Up to 3 – 4 hours if multiple joints need repair, the outdoor unit is roof-mounted, or the charge exceeds 2 kg.

Questions to Ask Your Trade

1. Are you F-Gas certified, and will you record the recharge in my logbook?

2. How will you check for leaks before adding new gas?

3. What refrigerant type and charge weight does my system need, and is it still legal after 2025?

4. Is your price fixed (includes call-out, gas and minor parts) or hourly after the first hour?

5. Do you provide a 12-month workmanship guarantee and manufacturer-grade refrigerant?

6. Will you leave a service sheet with pressures, temperatures and charge weight noted?

7. Are there extra costs for evening/weekend visits or difficult ladder access?

How to Avoid Surprises

• Note the model number and refrigerant label on the outdoor unit so the engineer brings the right gas and gauges.

• Provide clear access to both indoor and outdoor units and a nearby 13 A socket for the vacuum pump.

• Reserve a parking space close to the property for unloading kit and cylinders.

• Tell the engineer about any previous leaks or top-ups – repeated regassing without repair is illegal.

• Make sure the mains isolation switch is accessible and labelled.

• Ask for a digital copy of the pressure/temperature readings for your records.

With this guidance you know exactly what domestic HVAC regassing involves, what it typically costs in 2025, and the simple steps that keep the job safe, efficient and on budget.