I bought a MasterTemp and had expected to put it along my brick garage wall, which has no doors or openings. But when I opened the manual, it showed a diagram with a windowless/doorless/ventless exterior wall and an arrow showing that the heater vent had to be 4 FT from the wall. The page showed that it had been last revised in 2011.
When I compared it to the on-line manual I had been looking at in the months prior to buying the heater, I noticed that the diagram had changed. The 2007 version (which was not altered until 2011) showed the same diagram BUT showed a window on the wall and again indicated the vent had to be placed 4 FT from the wall.
Ultimately my plumber, pool boy, and inferences from other entries in the manual made me suspicious and I called Pentair. After multiple phone calls I ultimately learned that a newly revised diagram was issued in February 2012 and it showed the diagram to be an openless wall and an arrow showing the vent had to be only 6 INCHES from that sort of exterior wall (and 4 FT from a wall with an opening). I then spoke with legal, who confirmed what tech had assumed -- my manual had a typo and I could simply ignore the manual that shipped with my heater and I could instead refer to the most current manual, available on the Pentair website. According to the attorney, the heater unit itself has not changed, such that MY production lot of heater is not subject to my manual and then some alteration to the newly produced units could use the newly revised manual -- she says just must have been a typo that they at some point noticed and fixed in the 2012 revision. That said, she and tech and the attorney (at least the two I spoke to) had been completely unaware of the issue until I called, and were left with sort of reading between the lines to make a conclusion.
So . .. for any of you who install these units -- do any of you question that I can put my heater as close as 6" to my openless brick garage wall (I actually plan to put it 22" away or so, to allow access) and that ignoring the manual I was shipped is appropriate. I suspect it is just a typo, but would have felt better about ignoring a safety directive if they had been able to say "oh yeah, we figured that out and fixed it, sorry for the inconvenience . . ." instead of "huh, not sure . . . must just be a typo."
For anyone who wants to see the current version, go to this link and select "MasterTemp Manual" - it is the 11th product down I think. The diagram in question is the SIDE VIEW on page 18.
http://www.pentairpool.com/pool-owner/m ... n.php?s=28
Thanks for any warnings or assurances based on your experience with these sorts of things.