Re: Longevity of gas and propane pool heaters
For complicated reasons, I doubt that there is much reliable information on average heater life. If you are into such things, both "confirmation bias" and "selection bias" are in play.
I can, however, tell you things that affect life, negatively:
+ Volatile pool chemicals (muriatic acid, trichlor, dichlor, cal hypo)
are STORED or USED in the same enclosure or room as the heater.
+ The heater is not raised substantially
above the ground or floor level.
+ The heater is outdoors and not under cover.
(I know they can be operated outdoors -- but they don't last as long that way)
+ Pool pH is often below 7.0
+ Saturation index is too HIGHSI is a calculation of pH, temp, ionic strength, alkalinity and calcium. An almost universal error is to calculate SI at pool water temperature. The SI relevant to heater life must be calculated at the heater effluent temperature, which is hopefully the same as the temp inside the heat exchanger. The problem of concern is whether scale forms inside the tubes, causing local overheating of the metal, in the vicinity of the scale. Incidentally, I have never seen ANY evidence that low SI -- so long as pH is kept above 7.2 -- is relevant!
+ Chlorination takes place UPSTREAM of the heater,
whether by skimmer pills or a feeder.
+A chlorinator is installed downstream, but NEAR the heater,
AND the pump is on a timer, AND there is no check valve between the heater and the chlorinator. The problem can be avoided by setting the timer to run the pump -- briefly -- 2 or 3x per day in ADDITION to the regular interval.
+ The heater is killed by lightning or voltage surges,
because a surge protector was not installed. (This won't affect old millivolt type heaters, of course)
+ Spiders, ants, mice or rats, etc. inhabit the heater
in the off season.
And the big one:
+ Salt water chlorination (SWCG)
is used with a non-salt rated heater . . . which is most of them, except for the Hayward Universal models.
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Intermatic PS3000 Pool Surge Protector
Pentair 263042 2" CPVC Check Valve
Jandy 7305 2" CPVC Check Valve
Natural gas models:
Propane models:
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