Regulators
HOW TO CHOOSE YOUR REGULATOR
Every year the brands come out with a new and improved Regulator model at a hefty new price.
In reality the basic design of regs hasnβt changed in 25 years! The βnewβ models are simply cosmetic changesβ¦
Most of the brands source their regs from the same few factories. The regs are simple pieces of kit that are generally hugely overpriced and over-hyped.
Some even claim to have exorbitant breathing ratesβ¦Statistics such as 8500L/min! First of all β the average breathing rate is 15-20L per minute, 8500L/min is impossible.
Secondly an average cylinder only holds around 2700L of air so why on Earth would you want a Regulator to have a airflow of 8500L/minβ¦..
However, this is life-support equipment! So how do you look through the Marketing hype and buy yourself the best quality regulator for you and your family?
THE FIRST STAGE
The First Stage is the part of the Regulator that fits onto the Cylinder valve.
Its sole purpose is to regulate the air pressure from the Cylinder to 10 bar above the ambient pressure.
There are 3 different types of First Stages:
UNBALANCED PISTON
This is the most basic Regulator Design using a simple piston system. Water comes into the moving parts and pushes against a Piston, thereby measuring the ambient water pressure. On each breath the piston moves allowing the air through from the cylinder. There is a High pressure (from the cylinder) and a low pressure (from the water) on either side of this piston, so it is a High-friction design.
Advantages
- Cheap and cheerful
- Cheap to repair and service
- Most commonΒ rental gear
Disadvantages
- No problem with most dives, but sharing air at 30 meters could be a problem
- They get harder to breathe at lower tank pressures.
- Water, sand and salt in contact with moving parts
- No external adjustment
- Needs yearly service
BALANCED PISTON
This is a Medium Range Regulator Design using a simple balanced piston system. Water comes into the moving parts and pushes against a Piston, thereby measuring the ambient water pressure. On each breath the piston moves allowing the air through from the cylinder. The piston is however balanced therefore there is an equal pressure on either side of the piston, so it is less of a High-friction design when compared to the Unbalanced Piston. Better piston design therefore better performance.
Advantages
- Medium price
- Great performance
Disadvantages
- Water, sand and salt in contact with moving piston
- No external adjustment
- Requires yearly service
- OftenΒ advertised as a top of the line First Stage
DIAPHRAGM
This is a Top of Line Regulator. It consists of an internal diaphragm against the piston. Water comes into the regulator only as far as the diaphragm. It measures the ambient pressure on the diaphragm and so there is no water in the moving parts.
It is a low friction design and is very reliable.
They are also balanced and so they breathe beautifully.
Advantages
- Great performance
- Water not in contact with moving parts
- Externally adjustable
- Good versions only require servicing every 2 years
Disadvantages
- Often you will be convinced to purchase an environmental seal with a diaphragm and this can cause an instance called hyper balancing which can cause fluctuations in interstage pressure at depth.
UNBALANCED SECOND STAGE
The same unbalanced and balanced functioning found in the first stages, can be found in the second stages. Unbalanced Second stages have a piston that has a high pressure on one side and a low pressure on the other side. This creates an unbalanced, and high friction environment. These second stages do not breathe as well as the balanced Second stages.
Be aware that you may be tricked into buying a balanced first stage with an unbalanced second stage. These regs will not breathe well as they will be limited by the unbalanced second stage with regards to performance.
The unbalanced second stage is the most common type of second stage.
Advantages
- Simple
- Cheap
Disadvantages
- Go out of spec very quickly
- Require servicing every year
BALANCED SECOND STAGE
The same unbalanced and balanced functioning found in the first stages, can be found in the second stages. Balanced Second stages have a piston that has a balanced pressure on both sides. This creates an balanced, and low friction environment. These second stages breatheΒ exceptionally well. They are completely effortless.
Be aware that you may be tricked into buying a βfakeβΒ balanced second stage. They may have all the dials on the housing but this does not mean they are balanced. Look carefully inside the second stage to spot balanced vs unbalanced.Β
These second stages are not commonly found but are most definitely worth the extra money.
Advantages
- Last much longer before they go out of tune
- Only need servicing every two years
- Very smooth breathing
DisadvantagesΒ
- Price
Second Stages
There are two main types of second stages, balanced and unbalancedβ¦
ADDITIONAL FEATURES
Venturi switch
Nice to have as it stops the second stage from free flowing when bobbing around on the surface
Adjustable knob
Leave it fully open and only turn it in if you have a slight free flow. Saves going in to the dive shop for minor adjustments.
Metal second stage
Helps to humidify the air and prevents cotton mouth. But they are heavy in the mouth.
A dedicated humidifier is more comfortable.
The new hi-flexΒ braided type hoses are so nice! Well worth paying more.
If it an expensive reg it should have a metal orifice in the second stage. Ask if it has this.
Any of the regs will do the job. Some are more reliable than others but they all work. Look into the spares before you buy as several brands require a second bond before you can have it serviced!
