Suitability of the Aeris A1 reg for cold water diving?

[Wesley_R]

I recently got my OW certification, and will be doing most of my diving in Pugent Sound and other cold water locations.

I bought a used Aeris A1 set (1st and 2nd and octopus), and the shop I bought it from said it would be suitable for cold water diving (40 degrees).

I now question what the shop said, because the only mention of A1 temperature range I could find on the internet said "warm water".

Does anyone have personal experience with the A1 at 100 feet and 40 degrees? Should I be concerned about the reg freezing up or being hard to breath under these conditions?

 

[tbone1004]

hard to breathe no, freezing maybe. At 40 it should be fine, but it's an all plastic body with an unsealed piston so I would be careful....

 

[Jim Lapenta]

Personally I wouldn't take it that deep and in that cold of water. The recommended max low temp is 50 degrees for that reg as it is unsealed. If you were going to take it in water that cold I would be very careful not to over breathe it. That reg would not be allowed in the deep side of one of our local quarries due to it not being environmentally sealed.
It;s basically the Oceanic SP4 and when I did my Oceanic tech class this reg was one we spent a little time on. It's a good reg for rental fleets as it's fairly easy to service. But it is not a cold water reg. It's also an unbalanced piston so you may notice some increased resistance at depth.

"The Aeris A1 Regulator is commonly used for Warm Water" from the old promo materials

 

[Wesley_R]

Thanks for the replies. I will be shopping for a new reg, but I will never buy anything from Discount Divers Supply in Seattle again. I am at fault for not doing adequate research prior to buying the A1, but the salesman made it sound like the A1 was good for any water temp. Oh well, it's better to find out now than to find out at 100 feet!

 

[eelnoraa]

While not optimal, I don't think 40F will present a problem. It is a "flow by" unbalance first stage, meaning path of the gas in 1st stage, where a gas expand from HP to MP, is NOT where the 1st stage come to contact with water. In terms of freeze resistant, it is even better than balanced flow though piston design such as Scubapro Mk25. Here in Monterey, most if not all OW class student use this type of regulator. Water temperature ranging from 45-55 year around. 40F is quite a bit lower, but I wonder those who said it is NOT ok at 40F ever seem issue of this reg at 40F water.

I am also going to disagree with Jim about "It's also an unbalanced piston so you may notice some increased resistance at depth". Being unbalanced piston means increase of resistant as tank pressure drops. It has nothing to do with depth.

It isn't the best regulator out there, but it isn't that bad

 

[halocline]

It's also an unbalanced piston so you may notice some increased resistance at depth.

For someone that teaches a regulator service class, this is a surprising bit of mis-information. Balanced/unbalanced has nothing to do with depth compensation, and you should know that. Unbalanced piston regulators deliver lower IP as supply pressure drops, meaning as the tank empties. The way unbalanced and balanced regulators compensate for depth is exactly the same. Salesmen love to confuse the two issues because it encourages customers to buy higher end regulators.

To the OP, assuming your Aeris is a flow-by piston design (like sherwood and the scubapro MK2) it's more freeze resistant than most balanced piston regulators; there was a recent thread where it was explained in detail why this is. But since I have no experience with that specific regulator, I couldn't tell you what temp it's likely to freeze. I assume you have a drysuit? If not, don't worry about your reg; you'll freeze long before it does. If you do have a drysuit and are really diving 40F water at 100 ft (a bit on the edge for a newly certified diver, but I guess that's none of my business!) then consider getting a fully sealed regulator. Look on the bright side, its a lot less money than the drysuit.

 

[Jim Lapenta]

Good catch guys. Thought process does not always make it to the fingers. Too preoccupied with other things. Another reason I don't post as often as I used to.

Should have stated that "at depth as tank pressure drops you may notice some slight increase in resistance.'