For those of you new to UK diving, we wanted to write an easy-to-understand guide to regulators that perform well in cold water, below 10 degrees. In essence, a good cold water regulator is built with features that prevent freezing and freeflow. Below are a list of those features which is followed by our top 6 best cold water units.
Environmental sealing
This prevents water and debris from getting inside the first stage, thereby stopping ice crystals forming on crucial working parts. If the internal parts freeze you would have difficulty breathing. A dry ambient pressure chamber is usually covered with a hefty end cap and this feature can be seen on most diaphragm regulators. Piston regulators are rarely (but not always!) environmentally sealed as part of the piston is exposed to the surrounding water.
Heat Sink or Heat Exchange
A regulator gets cold not because of freezing water but because of gas expansion from the cylinder. This causes a drop in temperature inside your breathing equipment. Heat exchanger ribs or fins feature on the first stage (and sometimes also on the second stage hose inlet). They help to dissipate the cold generated by the first stage back into the surrounding water. The “exchange” is where it also draws in the warmth of ambient water.
Large purge buttons
In the event you get water in your mouth on a dive you may need to purge. Buttons on the second stage should be easy to find and operate when you are wearing thick gloves.
Diver adjustable venturi
It is the Venturi effect that causes a regulator to work - where moving gas causes a reduction in the surrounding pressure. However, in particularly cold environments this is when a freeflow can occur. A venturi lever on your second stage is designed to be turned down pre-dive to avoid the risk of freeflow (when doing a giant stride entry for example).
Diver adjustable inhalation effort
This knob is a breathing resistance control for fine-tuning of the flow of air during a dive. Some divers like to increase the flow with depth, others believe that in cold water your body needs to work harder, and you may need more air. This control can “cracked” open or closed.
Braided hoses
The general consensus is that nylon braided hoses perform better in cold water than rubber hoses. They also have a higher burst pressure for safety.
Our Recommended Regulators
Apeks MTX-RC Stage 3 Regulator Set
The original MTX (Military Technical eXtreme) was built for cold water use by the US Navy. This was followed by the MTX-R (Recreational) without diver adjustments. The MTX-RC has now added diver control to the second stage.
The swivel turret first stage has a satin finish and has been built with maximum heat-transferring ribs for better anti-freeze properties. The end cap prevents ice build-up over its hydrostatic diaphragm, eliminating the risk of freeflow. MTX-RC has two pre-angled high pressure and five low pressure ports allowing this reg to be one of the best for technical and sidemount applications.
The second stage now features both venturi and oversized breathing-effort adjustment controls to customise performance to the needs of the diver. The octopus has been tested in around 2-4 degrees of water to 60 meters depth.
SPECIFICATIONS
- First Stage Type: Balanced Diaphragm
- Environmentally Sealed: Yes
- Ports: 5 low pressure, 2 high pressure
- Second Stage Type: Pneumatically Balanced
- Diver Controls: Venturi & Inhalation
Scubapro MK19 Evo G260 Carbon Black Tech Stage 4 Regulator Set
The MK19 EVO G260 is a balanced and environmentally sealed diaphragm first stage that offers superb cold water performance and reliability. It has a swivelling low pressure turret for improved hose routing, including technical and sidemount.
The pneumatically balanced second stage has a rugged design with large diaphragm. It has metal valve body components for improved cold water reliability and a convertible housing for alternative hose routing options. It has a Black Tech finish for extra abrasion and corrosion protection and a lighter and tougher Carbon Fibre front cover.
The Scubapro MK19 EVO G260 Carbon Black Tech Stage 4 Regulator Set includes a super reliable R195 Octopus, a compact twin console and a stylish regulator bag to protect it.
SPECIFICATIONS
- First Stage Type: Balanced Diaphragm
- Environmentally Sealed: Yes
- Ports: 5 low pressure, 2 high pressure
- Second Stage Type: Pneumatically Balanced
- Diver Controls: Venturi & Inhalation
The Leg3nd range offer one of the best breathes available for recreational divers. There are 3 models which share an identical first stage, with second stage features added as you go up the scale.
The chromed first stage is fully environmentally sealed with patented ACD device (Auto Closure Device) to prevent water and contaminants entering, thus extending its life. The stylish design now includes heat-exchanger ribs which have improved its cold-water performance. There are four low-pressure and two high-pressure ports which are positioned at an angle to help better hose routing.
The choice of compact second stages all have large purge buttons ideal to operate when wearing thick dry gloves. Additional heat exchanging fins on the second stage hose inlet results in increased diving performance. We also like the over-sized lipshield which keeps your lips warm!
The Leg3nd has a co-moulded venturi control lever; the Leg3nd MBS has an added breathing resistance control on the second stage called a Master Breathing System (which allows the user to fine-tune the breathe through one control knob); the Leg3nd Elite has a combination of both.
SPECIFICATIONS
- First Stage Type: Over-Balanced Diaphragm
- Environmentally Sealed: Yes
- Ports: 4 low pressure, 2 high pressure
- Second Stage Type: Pneumatically Balanced
- Diver Controls: Venturi (Leg3nd), Inhalation (leg3nd MBS), Venturi & Inhalation (Leg3nd Elite)
The Mares Dual ADJ 62X is 10% lighter than its predecessor the Dual ADJ 52X and a high performance all-rounder. The first stage features a patented NCC system (Natural Convection Channel), which assists in temperature exchange and also boasts a Dual Flow Control (DFC) which delivers plenty of air at any given depth.
Manufactured from marine grade brass and coated in beautifully looking pearl chrome, it has four low pressure and two high-pressure ports offering cable routing to suit multiple diving styles.
Made from ultra-light techno-polymers, the stylish second stage has been designed with Vortex Assisted Design (VAD) which channels air through the bypass directly to the mouthpiece. This increases the sensitivity during inhalation, making breathing easier wherever you are in the water.
SPECIFICATIONS
- First Stage Type: Balanced Diaphragm
- Environmentally Sealed: Yes
- Ports: 4 low pressure, 2 high pressure
- Second Stage Type: Pneumatically Balanced
- Diver Controls: Inhalation
Atomic ST1 Regulator, Octopus & Miflex Console Regulator Package
The Atomic ST1 is a high-end regulator made of a special grade of 316 Stainless Steel that is 100% recyclable with superior cold water properties unlike conventional chrome brass regulators. The ST1 offers corrosion-resistance without any chrome or nickel-plating processes that create environmental concerns. It has the durability of titanium without the price tag.
This lightweight, balanced, Jet Seat high-flow piston regulator is freeze-protected and environmentally sealed to prevent any outside contamination. Atomic employs a conical seat and blunt-end piston which is the most reliable seat system in the industry, enabling the seat to go 2-years or 300 dives without service.
The ST1 second stage offers the same renowned Atomic designs as the T3 Regulator. Atomic are the only manufacturer to use a titanium inhalation lever, spring and poppet seat along with the patented AFC Automatic Flow Control, LP Seat Saving Device and Rapid Adjustment Knob. A stainless steel Comfort Swivel hose allows 30°effortless range of motion without restricting any air flow. This releases some of the tension from your jaw muscles during your dives.
The Stage 4 set also includes the Atomic Z2 Octopus featuring zirconium corrosion proof components along with titanium inhalation lever spring and poppet seat. Plus a Miflex Double Console.
SPECIFICATIONS
- First Stage Type: Flow-through piston
- Environmentally Sealed: Yes
- Ports: 4 low pressure, 2 high pressure
- Second Stage Type: Pneumatically Balanced
- Diver Controls: Automatic Venturi & Manual Inhalation
Scubapro MK17 C370 & R095 Octopus Regulator Set
The Scubapro MK17 EVO C370 is a high-performance regulator package with an environmental seal preventing impurity ingress. An oversized end cap and heat exchanging fins improve the anti-freeze properties of this workhorse. It contains two high-pressure and four high flow low-pressure ports to attach all necessary scuba equipment.
The second stage is fitted with a pre-dive venturi control and diver adjustable inhalation that allow the diver to customise the breathe and performance of the regulator on the fly. It has a fibreglass reinforced nylon casing with a streamlined exhaust tee. This value for money regulator is suitable for travel as it is lightweight and compact, which also makes it a hit with female divers.
This stage 3 set comes with the Scubapro R095 Octopus which has been pre-tuned for safe and uncomplicated use.
SPECIFICATIONS
- First Stage Type: Balanced Diaphragm
- Environmentally Sealed: Yes
- Ports: 4 low pressure, 2 high pressure
- Second Stage Type: Pneumatically Balanced
- Diver Controls: Venturi & Inhalation
