Should I be concerned that my pump is right next to my heater?
Yes.
Everything is outdoors and fully ventilated.
That will help the issue, but how much depends on your prevalent wind direction, how much wind, and how much per day there is still air.
Just curious if the fumes could have an effect on metal over time since they are so close together.
There's a thread here that describes how an entire garage's tools got corroded before it was discovered the culprit was the fumes venting from muriatic acid (MA) jugs stored inside (don't do that, MA can be stored outside with no ill effects to the acid).
There are two solutions to eliminate, or at least minimize, the MA's corrosive effects on your pad's equipment:
One is to relocate the tank as far from anything metal as possible. Even stainless steel will succumb to MA fumes.
The other is to vent the tank with a tube and locate the other end of the tube as far away as possible. My Pentair acid tank is designed specifically to be able to do this. The tank is 100% air tight, its lid is sealed with an o-ring, and then the tank has a venting port to which I connected a small 1/4" tube that runs away from my pad and vents fumes on the other side of a yard-dividing vinyl fence.
Does your tank seal air-tight? And if not, can it be made to? Does it have a vent port, or could one be added?
You can't just seal the tank, you also have to have the vent, because, in addition to venting fumes, the vent is there to allow air in and out of the tank: air out as the tank warms up each day, and air in as it cools, or as the acid level drops.
The other end of the tube gets located away from the pad, but also away from anything else metal: fence hardware and fasteners, window hardware, downspouts, etc. As far away from all metal as possible. I pointed the end of the tube down, slightly, so that rain water couldn't collect in the tube and mess with the air flow.
If neither the vent nor moving the tank is an option, technically there is a third semi-solution. You could dilute the acid in the tank and dispense more each cycle. This would somewhat reduce the corrosion effect since the fumes would also be diluted. I don't have any direct experience with this, or how well it might work, or at all, but it's a possibility.
Sidebar: have you considered what would happen if your system malfunctioned and emptied the entire contents of the tank into your pool? My system has several safeguards to minimize this possibility. The primary one is the size of the tank. It holds just under four gallons, and I rarely fill it with more than three. I dilute my 31% acid 1:1. So there is anywhere between 0 and 1.5 gallons of MA in the tank at any point in time. Should my system fail at the worst possible moment, the most my pool would receive is 1.5 gallons of 31%, which will crash my pH for a while, but not cause any undo harm to my pool or equipment, or more importantly to any swimmers.
If your tank is full with 7.5 gallons of 31% MA, well, just think about that. Diluting your acid 1:1 or more would have the benefits of:
- less wear and tear on the pump and injector,
- less acid in the pool if a failure empties the tank,
- and less acid in the fumes.
And reducing the number of gallons in the tank will also make it safer. Less convenient, granted, but less of a hazard.
Something to think about...
