I have recently purchased a Mountain air gap for a kithen R.O. faucet. Once the system was installed and bled we noticed the air gap making a very loud gurgling. We removed and inspected for drain blockages, there were none. Then we drilled out and increased the drain hole to 3/8"where the saddle valve ties into the sink drain. No luck, it still gurgles. What can we do???????????

this is an easy fix and quite common. I found that removing the drain line where saddle is mounted and clean it from the inside.
A common leaking problem in most taps is the "air gap leak." It occurs when water leaks through the hole on an air gap faucet.
An air gap is a vital component of the reverse osmosis system. It prevents the back flow of water into the reverse osmosis unit. Instead, the air gap directs the excess water into the drain lines.
When a lot of debris accumulates in the drain line, it clogs up, creating back pressure that forces water to flow out through the air gap. Unfortunately, the back flow can flood your countertop.
To fix this problem, remove all the debris accumulated in your drain line to allow water to flow smoothly. You can use a wire brush or a pipe cleaner to clean out the drain line, starting from the end connected to the system's drain saddle.
You should also clean the system's drain saddle and ensure that it's properly aligned with the drain line. That's because the drain saddles can sometimes shift away from the drain lines.
To avoid air gap leaks completely, treat the drain line regularly using a natural cleaner that can dissolve the solids blocking it. Also, avoid flushing big chunks of food down the drain line.

is there a precharge of air in your tank. when empty of water th?re should be about 1 bar or 14psi of air. water must be able to empty from tank. pump air in until all water is gone. if unable to empty tank has failed. also if a pumped unit, when changing filters ensure all air is bled through pump before turning it on toprevent air locking inside pump

Possible that the system was not bled properly, Once the brakes are serviced specially the hydraulics system,then it is important to see if there any AIR lock within the fluid system . The air has to be bled off till the pedal locks firmly. Also the brake pads must be set to close in with the same gap in all the four wheels.
This will give the best performance on your brakes.

Start from the master cylinder and check if the housing is bad or worn out, specially the buckets. Then check all the wheel cylinders, the buckets before the system is charged and bled out.
Once the air in the sytem is fully off , the pressure must come on. If not make sure that the wheel cylinder travel is closer by adjustment .
You must get the pressure once there is no gap in any of the cylinders and the system is free from air lock.
Credit me if this solves.

An RO drinking water air gap faucet would be the ideal faucet to purchase for your RO system. Here are a few options you can choose from that may come in brushed nickel: http://www.freshwatersystems.com/c-821-ro-drinking-water-air-gap-faucets.aspx

If there is an air gap (located in the sink, near the faucet), check to see if it is clogged. Unscrew the top cap and see if there is anything blocking inside. Note: If there is no air gap installed, the dishwasher might not drain properly.

If the drain hose is clogged, the dishwasher will not drain. If there is an air gap installed, it is very common that a hose going from the air gap into the garbage disposer is clogged. Remove and clean the hose. Make sure to reattach the hose before starting the dishwasher.

Note: If you recently had a garbage disposer installed, it is common to overlook removing the drain plug.

OK, now I understand. First, on the Reverse Osmosis Membrane Housing Outlet Ports there is only a Check Valve attached to the Permeate (Pure Water) Port, not the Concentrate Port (Drain Water). The Permeate line is what fills the storage tank, so you don't want back pressure from the tank reversing into the membrane filter which could severely damage it. So, there is a high Risk for Sewer Water to Back-flow into the Membrane Filter and Contaminate it as it is discharging water to the sewer drain if there is any noticeable pressure restriction in the drain distribution manifold. Second, this is why "Air-Gap" Faucets are supposed to be used when installing Reverse Osmosis Systems. With an Air-Gap Faucet, there are three (3) attachments for tubing at the base of the faucet, and a small hole drilled out underneath the lever or handle of the faucet. The 1/4" pressurized drain line tube from the RO System attaches to the 1/4" barbed fitting under the faucet base, then a 3/8" drain line tube attaches to the 3/8" barbed fitting. So when the drain water is pumped up to the faucet under pressure, it returns to the sewer line under Gravity, or No Back Pressure. Then, if the plumbing becomes restricted in any way that the RO Unit can't drain into the sewer under gravity feed, the hole drilled in the base of the faucet allows the back pressure to be escaped to the atmosphere, and if necessary drain water out of the hole until the plumbing pressure restriction can be resolved. This eliminates the possibility of a reverse flow pressure situation from occurring. Hope this helps, and you can always visit us online at www.puresafe.com We have filter cartridges for all makes and models of RO Systems, and 1/2 micron filters that no one else in the trade is using at this time. Thanks, Victor

If there is an air gap (located in the sink, near the faucet), check to see if it is clogged. Unscrew the top cap and see if there is anything blocking inside. Note: If there is no air gap installed, the dishwasher might not drain properly. If the drain hose is clogged, the dishwasher would not drain. If there is an air gap installed, it is very common that a hose going from the air gap into the garbage disposer is clogged. Remove and clean the hose. Make sure to reattach the hose before starting the dishwasher. Note: If you recently had a garbage disposer installed, it is common to overlook removing the drain plug.

Option 1 ; Cap off the sprayer.  Option 2 ; Relocate the air gap as high as possible under the sink but then you have no drain under it in case it backflows (it is really a vacuum breaker ,  one way check valve) Option 3: Take back the faucet and get one of those that the spout is also the sprayer.

Low inlet water • Make sure inlet water temperature is at least
120°F (49°C)
• Run water at the nearest faucet prior to
starting the dishwasher to insure optimal water
temperature.
Water pressure is low • Turn on a faucet. Is water coming out
more slowly than usual? If so, wait until
pressure is normal before using your
dishwasher.
Air gap is clogged • Clean air gap.
Improper rack loading • Make sure large dishware does not block the
detergent dispenser or the wash arms.