Heated vests

[DavidFL]

I bought a Thermalution vest a couple of years ago ( the version for wetsuits with a wired controller); have only tried it in the ocean once, and in that attempt I got a strange flashing indication on the LED controller (and no heat). I tried a couple of times to get some kind of support/answer from the U.S. vendor/distributor but failed. To be honest I didn't follow up very hard; it worked good swimming laps in a pool in the winter months when I tried it out.

 

[Scott]

As someone that is still in the information gathering stages, I’ll follow with interest.

I like the Thermulation idea since I could use it with a wetsuit or both my drysuits without having to purchase multiple bulkheads for the drysuits.

Cost are fairly compatible. To have Light Monkey convert my canister with a plug, controller, inflator bulkhead and vest would be around $600-$800. Depends on which heater garment is used.
Thermulation, $789 according to their site.

 

[Gareth J]

I have been using a LOLA (czech) vest for 3 years. We first got vests in preparation for a trip to Iceland.

They have been very good.
I have noticed, that it does keep me warmer, even if it isn't turned on. There must be a thermally reflective layer.
Generally its set at its lowest setting. It's too uncomfortable at its highest setting.
On of my buddies almost gave himself heat stroke, when he turned the vest up, rather than down, during a December dive - idiot .

I did make sure that the battery is outside. If there is any failure I can either physically disconnect the battery, or cut the lead .
I have talked to too many people who have suffered either actual physical burns, or come close.
Once you are committed to a decompression profile you can't just 'get out' if you feel to hot. I have heard of a few people that actually flooded the suit in an attempt to cool off.
Also, stay away from motorcycle vests and the like. The worst incidents appear to be from vests not designed for diving.

One thing to be aware of is that if your battery fails late in the dive, and you cool, it can cause complications with your decompression profile. You go from blood circulating well to blood returning to the core as you chill. Meaning you have high gas loading in your extremities, from the good circulation when you where warm. To poor off gassing of the extremities as your outer temperature drops and your circulation shuts down moving the blood to your core.

Gareth

 

[king_of_battle]

My gf borrowed a thermalution to wear under her everdry drysuit with water temps around 36F 2 weeks ago. She said it was nice but she didn't care for it only hearing her back and said she probably would just layer up instead of buying one in the future. The guy we borrowed it from swears by it so your mileage may vary.

 

[macado]

I've been using a Thermalution vest for a couple seasons in New England waters under my drysuit. I also use mine under my wetsuit when I teach in the pool. The big advantage to me is no bulkhead or additional E/O cord / external battery. I like the fact that I can continue to use my vest if my drysuit floods (a lot of other vendors tell you that you should turn heat off if you flood the suit)

Overall, the Thermalution vests work pretty well but I am starting to hit the limits of longer runtimes with 2 dives. I try to keep mine on low or medium and typically do not turn mine on until at least 20-30 minutes into the dive if I can help it. If I'm only doing one dive then I'll use the high setting.

I've found the vest makes a huge difference in my comfort level when diving in water from med to high 30s to low 40fs (35f-45f). Above ~45f I'll still wear the vest but I can layer more appropriately and not really depend on the heated vest like I do when I'm diving in 38-39f water.

If you're going into any sort of deco I recommend saving the vest for that. You basically want to ensure that you don't run out of battery when you need it most. If your body is chilled at the end of your dive then you will not be decompressing and off-gasing very efficiently which can increase your risk of DCS.

There is a very interesting study you can read here: The Influence of Thermal Exposure on Diver Susceptibility to Decompression Sickness.

The biggest cons for the Thermalution vest for me are they aren't as warm as other vests on the market. They don't publish how many watts of heat the vests produce.

Having said all, I'm working a DIY solution for a new vest that has a longer runtime and provides heat over a larger area. I just haven't installed the bulkhead in my drysuit yet to test it but it works great on land.

I purchased a Light Monkey bulkhead and converted and installed an E/O plug on an old can light battery I've had. I've purchased two thermal pads from light money (20W each for a total of 40W of heating) and sewed them into a base layer. I didn't go with a controller since the setup only provides 40W heat so I plan to toggle it on/off when I need it.

Light Monkey | Equipment for Technical, Cave, and Wreck Diving
Light Monkey | Equipment for Technical, Cave, and Wreck Diving

 

[Chris H]

I have a external Light Monkey canister with their heater valve inflator. I had BTS-DIR/Typhoon Icebreaker for several years. It was OK, but it didn’t breathe at all, so sweaty base layer was inevitable. When it died, I picked up a Tourmaster Synergy Motorcycle vest and it has bee great. I understand there are naysayers on the motorcycle vests, but there are people using them on much bigger dives than I’ll ever do. YMMV.