Actually, there is a solution for HPV-22(non-B) owners. You can do the same thing that the "B" models do with their switch. If you are replacing a lot of water in the batteries, and concerned about the 14+ readings the HPV is giving, you might want to follow the advice of Dave Reuter of AM Solar:
'The best solution to your issue is to purchase a new HPV-22B so that you can switch the charging mode to a 13.2 float voltage ("shore power"). The other option is to change dip switch (located in the upper left hand quadrant of the circuit board) # 2 to from "norm" to "low". This will change the charging set point to 13.2V just as the "dry camp/shore power" switch does. Obviously, this is not real convenient as it requires that you remove the 4 face plate screws and pull the controller out of the wall to access the dip switch block. By the way, the Bulk/Taper set point voltage setting for the HPV-22 is 14.3V.'
If you remove the unit from the wall, you'll immediately see the row of dip switches on the upper left of the back panel; flip the #2 switch, and reinstall. You should see battery water use drop dramatically.
It is super easy to upgrade to HPV-22B. The boxes are identical and can be swapped in, in about 10 minutes. You can order an HPV-22B from AM Solar, and they may give you credit for the HPV-22 after you return it to them.
Given that the non-B model has the dip switch arrangement, you could probably modify the original by adding a toggle switch to it. It wouldn't be quite as clean as a real 22B, but it should work the same.
Contributor: Jon, Dave
12 Jun 2011