Thanks for the info RibFixer. Now that you have explained about the large baffles, I can see from the diagrams in the instruction manual why, as you say, it could look like a large deflation when an adjacent tank is emptied.
However, i'm getting mixed instructions regarding the order of inflation and from your post RibFixer, note now that even the Zodiac manual could be interpreted in more than one way.
Im just trying to get the correct procedure. I thought I had it but I am now not so sure as people have posted different versions.
In the Zodiac manual, it gives a small table of assembly procedure. I had previously looked at the more detailed inflation instructions as the definitive version. Taking the relevant bits out of the assembly procedure table, it reads as follows:
2. Install bow stowage box
3. Activate values into inflation position
5. Begin inflation of the boat (not completely) - this is the extra step from the detailed instructions below.
6. Inflate the H2P floor to correct pressure
8. Finish installation of boat to correct pressure.
Now, looking at the detailed instructions, it reads as follows (3 sections):
Cadet fastroller Active-V - Air floor inflating procedure
A: Inflate the active-v floorboard/keel assembly
- Before inflating, open out the boad and position the keel in the central band of the bottom and on the floorboard axis (centred between the positioning pins).
- First, inflate the keep-floorboard assembly to its rated pressure
- Check that the keel inflated perpendicular to the floorboard and that it is still positioned on the central band of the bottom (otherwise reposition)
- Inflate the main bouyancy tube
- Press the floorboard down around the edges to fit it into the follow of the angle
1. Activate the valve into inflating position
2. (with foot pump) Inflate in position A (low pressure) until it becomes difficult to operate
3. (with foot pump) Finish inflation in position B (high pressure) until you reach the correct pressure (800mb/11.3psi)
B. Inflate the main buoyancy tube
2. Inflate the main buoyancy tube and the keel (assume this is for aero model not active-v) until it (the foot pump) becomes difficult to operate. Correct pressure = 240mb - 3.48 psi
It then has a series of diagrams explaining not to inflate a compartment to full pressure if other compartments are totally inflated. Suggests 50% then 100% inflation but im not sure if this applies to pressure or volume.
As you can see, the detailed instructions make no mention of inflating main tubes partially before floor/keel where as the procedure table says 'begin inflation (not completely)' and fails to mention what 'not completely' means, ie is it until they start to raise into shape, 50%, or something else.
To add to the mix, I have just bought a Bravo BST 12 HP pump with auto cutoff between 100mb and 800mb. Im too old to pump with my foot and want to enjoy being out on the water rather entertaining onlookers. So I'm not sure if I initially partially inflate main tubes by eye to 50% by volume, or to 100mb (approx 50% by pressure) then fully inflate.
I think inflating the bow tube first looks most logical. Presumably I deflate last, albeit in quick succession.