I'm looking for a light, compact, and warm setup for diving. A few questions on the Thermolution stuff:
1. Does the -70m Compact Dive series heat up the armpit area? I tend to lose a lot of heat around this area. The vest version would be pretty cold for me I think.
Thermalution Heated Undersuit -70M (Shortsleeve)
2. Will this fit over a freediving suit with integrated hood? The freediving suits require shampoo or conditioner to get into, but when it's on, the seal is very very good and there is minimal water exchange with the outside.
3. What I have in my head is I could wear the -70m Compact Dive series with a thin and light 3mm freediving suit, and it might just be as warm as a 7mm freediving suit, while being a heck of a lot lighter and more compact. I don't really lose heat from my legs and arms.
I own the 70M shirtsleeve version. I love it. I've become pretty wimpy in my older yrs but it allows me to keep diving in water temps that would really chill me and make me not want to dive.
1. No the armpit area is not heated. There are two square areas, upper back and lower back, that are heated with coils.
2. You need to wear this next to your skin for it to work more efficiently.
3. The warmth of the shirt reminds me of the warmth of peeing in your suit... Pls don't ask how I know that.
When I first bought this shirt, I thought I could get rid of my 3mm core warmer. Didn't work out that way. I need the core warmer to keep the shirt close to my body. Maybe your suit will do the same. Too much water/space in the suit makes it less effective. My suit is tight but the core warmer keeps a thin layer of water really close to my body and it does not get flushed or moved around.
I normally turn on the shirt just before getting in the water. It takes a few minutes to heat up. If I dunk in the water first and get a layer of cold water in before turning on the shirt, it takes a long while for the suit to feel comfortable. YMMV in a freediving suit. This way when the water does come in, it feels really good vs a cold chill. When I first purchased the shirt, I bought for my size in the chart. It was too small for me as it was very tight and restrictive (arm movement) and not comfortable. I went up the next size and it is just a tad too big but it's a more comfortable fit. If I'm not comfortable diving, I don't want to be diving. I also wear this heated vest under a sleeveless core warmer. This tightens up the contact of the heating coils to the body and makes it work very well. If there is too much looseness, it will not function as intended. The shirt needs to be tight on the back heating panels, preferably against the skin. Getting a thin layer of heated water in the suit and keeping it in will work the best. On top of the core warmer, I wear a 7mm. Most of the time in the NE, I am toasty warm from the beginning of the dive to the very end. I can do 2 dives on one charge of the battery so far. Some of my dives are 60-75 mins long. On some of the longer dives, the battery ran out as I was coming in. I also use the lowest setting most of the time. If I get a good chill going through a thermocline, I'll turn it up for a moment then back down. Boy does it feel good when the heat kicks in!
As for the extremities being cold... Not. When my core is warm, it moves warm blood out to the arms and legs and keeps me warm. I've been in water that was low 50ºF and was glad to have the vest. My arms and legs were colder, chilled, but it certainly made a difference. It made the dive tolerable.
I really like the shirt but I don't like the controller on the coiled wire. I would much prefer a straight wire which would be easier to route to the outside of my suit. Think about getting the remote controlled one. I've heard of some problems with the remote version, but maybe it's fixed or the problem was over exaggerated. The coiled wire creates a small inlet for water to get in and is not as comfortable against the body as a straight wire would be. Most times I don't even feel the wire but I'm splitting hairs. And if Thermalution is reading this, they should change it.
