VRF Air Conditioning and VRV Systems

VRF air conditioning in London

VRF air conditioning (variable refrigerant flow) is a system in which one outdoor unit serves many indoor units. It sends each indoor unit only the refrigerant it needs, so every room or zone can be controlled on its own. It suits larger buildings with many rooms, such as offices, gyms, schools, restaurants and retail units. Climate Flow Limited installs, services and repairs VRF and VRV air conditioning across London and surrounding areas.

Is VRV the same as VRF?

Broadly, yes. VRV (variable refrigerant volume) is a trademark of Daikin Industries. Daikin describes it as a technology that circulates only the minimum amount of refrigerant needed for the heating or cooling being asked for at the time. VRF is the general name other manufacturers use for the same approach. So VRV air conditioning is Daikin's version of VRF.

We install and service Daikin VRV and Mitsubishi Electric City Multi VRF systems. We also install and service air conditioning from Mitsubishi Heavy Industries, Fujitsu, Toshiba, Panasonic and Samsung.

How a VRF system is put together

A VRF system has three parts:

• The outdoor unit serves every indoor unit on the system.
• Refrigerant pipework runs from the outdoor unit through the building.
• The indoor units deliver heating or cooling to each room.

Each zone has its own controller, so the people using that space can set it independently of the rest of the building.

Several types of indoor unit can share one outdoor unit. A ceiling cassette is an indoor unit set into the ceiling. On Mitsubishi Electric's City Multi VRF range, one outdoor unit can serve up to 50 indoor units, including ducted, ceiling cassette, wall-mounted and floor-standing types.

Heat recovery or heating-or-cooling

VRF systems come in two broad types.

A heating-or-cooling system runs on a two-pipe refrigerant circuit, with branch pipes to the indoor units. It works in one mode at a time: every indoor unit cools, or every indoor unit heats.

A heat recovery system can heat some rooms and cool others at the same time. It does this by moving surplus heat from the rooms being cooled to the rooms that need it.

The survey is where we decide which type fits, based on how the building is used.

What a VRF installation involves

A VRF installation is planned around the building, because the pipework runs through ceilings and risers (the vertical service shafts between floors) between the outdoor unit and every indoor unit.

1. Survey. An engineer looks at several things: the rooms and how they are used, where the outdoor unit can sit with clear airflow, and the routes for pipework, condensate drains (the pipes that carry away water collected by the indoor units) and controls.
2. Design and quote. We size the system and choose the indoor unit type for each room. The work is then set out in a no-obligation quote.
3. Installation. Pipework, indoor units, the outdoor unit, drains, wiring and controllers go in. The work is planned with you around your opening or working hours.
4. Commissioning and handover. The system is pressure tested, filled with refrigerant (charged) and run in every zone. We then show the people on site how to use the controllers.

Signs a VRF system needs attention

Watch for:

• A room that no longer reaches the temperature set on its controller.
• An error code on a controller or on the outdoor unit.
• Water dripping from an indoor unit.
• Ice on the pipework or the outdoor unit, or a hissing sound near the pipes.
• New noise or vibration from the outdoor unit.

What does VRF maintenance include?

A VRF maintenance visit cleans, inspects and tests the system so it keeps running as designed. At Energie Fitness Gym, we carried out maintenance on a Mitsubishi Electric VRF system.

What we check:

• Filters and indoor unit coils, cleaned
• Condensate drains and pumps
• The outdoor unit coil and the airflow around it
• Controllers and any stored error codes
• Running temperatures and performance in each zone
• Refrigerant leak check, where the system is in scope of the F-gas rules

What the F-gas rules say about VRF systems

If you operate stationary air conditioning, you are responsible for having it checked for F gas leaks. Equipment holding F gas equivalent to 5 to less than 50 tonnes of CO2 must be checked at least once every 12 months. The threshold is measured in tonnes of CO2 equivalent, not kilograms of refrigerant. Whether a VRF system is in scope therefore depends on its refrigerant and how much it holds.

Anyone who works on equipment containing F gas needs their own F gas qualifications. A company that installs, repairs, maintains or decommissions air conditioning for others must hold company F gas certification. Climate Flow is F-Gas certified.

Which buildings use VRF air conditioning?

VRF suits buildings where several rooms or zones need their own settings from one system. Typical examples are gyms and leisure sites, offices, schools, hotels, restaurants and retail units. Our work at Energie Fitness Gym is one example.

You can see more of our air conditioning and refrigeration work on our projects page.

VRF and VRV air conditioning from Climate Flow

Climate Flow Limited installs, maintains and repairs VRF air conditioning and VRV systems across London and surrounding areas, with 24/7 emergency callouts. Our full list of services covers commercial refrigeration, air conditioning, and domestic heating and boilers. Climate Flow Limited, 2 Engineers Way, Wembley, London HA9 0JS. Call 020 3488 5452 or request a quote.

This guide is general information, not a survey or a quote for your site; every system is different, so an engineer needs to see yours before any work is priced.