Feeding Stenner pump straight from MA jug

[jmastron]

I just installed an SWCG and am considering whether to repurpose the chlorine Stenner pump for Muriatic Acid injections. I have a 15 gallon drum that would have to be emptied and cleaned, but don't really need or want to keep that much MA around, nor do I really want it inside the pool pumphouse where it can corrode things. We use about a gallon of MA a month. I was thinking of just feeding the MA straight from the gallon jugs it comes in by drilling a hole in a cap for the feed tube. Has anyone done this? It eliminates handling/pouring of acid, at the cost of having to check and switch jugs every month or so.

When I installed the SWCG, I put in a second injection point tee, so I have the option of injecting before or after the SWCG. From other threads, it seems best to inject acid after, since while acid is used to clean the cell, it's better to do that intentionally when needed than to risk overdosing and reducing the cell life that way. Which side do those of you who have both an SWCG and MA injection use?

 

[JoyfulNoise]

Inject MA after the SWG, if is safer. Also, ensure that your injection point has some kind of check valve on it to avoid acid dribble out of the line and running back to your SWG or heater. In this instance, putting a check valve on the pipe after all sensitive hardware but before the acid injection point would be the safest thing to do (similar to how luck chlorinators are always plumbed with a check valve before them to protect the heater).

Why not use the stenner tank but just dilute the acid 1:1 or 1:2 with water? It will reduce the acid fumes to nothing at all and be safer than concentrated acid.

 

[Baumeister]

I maintain the Stenner injection pumps at our neighborhood pool club for both liquid chlorine and MA injection. I think you've got a great idea to minimize acid handling and fuming.
I use a hose vented acid tank, with the vent hose line running a short distance away from the equipment, which is all outside. Really bad design that I'd love to re-work(but no budget), my injection lines cross the electrical main, control panels, timer boxes.
Be sure to use a bottle base or carrier crate with blocking to minimize the risk of the bottle getting knocked over inadvertently.