Ap100 extremely hot on the bottom, is that normal?

[davenmandy]

I just recent had my ap100 diaphragm blow on me after 9 months of usage, I would have been happy with 12, big thanks to Pondmaster for sending me a kit for free even though it wasn't under warranty.

Replacing the diaphragm wasn't terribly hard, but the final placement of the last diaphragm was a bit tricky. I replaced the filter floss in the bottom chamber where the gasket that gets replaced is because it was a bit dirty, the filter floss I had was slightly thicker but honestly not by much. Pump runs fine, I believe at the same capacity as before.

I noticed when moving the pump yesterday that on the bottom it is extremely hot, to the point that you honestly can't touch it much. Really hot. The sides are hot too, but definitely manageable - nothing like the bottom. I don't have anything to compare it too because since setting the pump up the first time I honestly didn't touch it so I don't know if they are always like that, I do know the 3/4" air tubing always got kind of hot and it still is, not sure if it is more though, hard to tell.

Does anyone know if this is normal? The pump is sitting on a wood shelf next to some tools and materials, it is on the rubber pegs, last thing I need in my life is a fire. Just a bit concerned the diaphragm replacement didn't go as well as I thought or that filter floss is too thick after all, I'm not kidding when I say the difference was very miniscule and maybe not even in thickness but slightly in density.

millerkid519 DB junkie

 

[millerkid519]

I think the density of the floss may have something to do with it getting hotter but on the other hand it's hard to say without knowing how hot it was before

 

[davenmandy]

I wonder if the foam is really makeing that much of the difference, it was basically identical, my bet is no and if I were a gambling man I would guess that it is always that hot on the bottom, but on the chance that I am wrong I would love someone with an AP100 to comment on theirs.

 

[DB junkie]

Just checked my 2 (3rd destroyed itself to the point its not repairable)

1 is hot like you described - the one I just rebuilt, the other I can actually pick up. Wonder if that means it needs rebuilt..... lol

I just blow the stuffing out with compressed air.......

Are you sure the ratings on your stones/diffusers exceed that of the pump so that the pump isn't being restricted?

 

[davenmandy]

Just checked my 2 (3rd destroyed itself to the point its not repairable)

1 is hot like you described - the one I just rebuilt, the other I can actually pick up. Wonder if that means it needs rebuilt..... lol

I just blow the stuffing out with compressed air.......

Are you sure the ratings on your stones/diffusers exceed that of the pump so that the pump isn't being restricted?

You know what, no I don't know if the stones are restricting it. I have 4 aluminum oxide diffusers, 1/4" barbs on them, 3"x1.5"x1.5" rectangular. Does that sound like it may be restricting air flow?

Interesting one of yours is hot and one isn't. Did you find it a bit difficult to properly place the second diaphragm after securing the first one? Wondering if you have a trick to it, it doesn't align the best after the first one is secure because of positioning, or at least it didn't this time. Your air line get a bit hot too?

Thanks.

 

[DB junkie]

You'll need to research your diffusers and get a cfm/lpm rating for them. Takes some pretty massive diffusers to let the ap 100s breath. I run 3 of the 10" diameter rubber diffusers in my 90 gallon reactor. I think they have 3/4" inputs on them and can suck up like 5 cfm ea.

Hose is a little warm on both and the Jehmco pump I run so assume that's normal.

What I do is pop the rectangle off the top of the thing and use shims to center the stupid magnet thing that attaches to the diaphragms. I put the diaphragms on that magnet piece first to be sure they're centered, then shim, then wrestle the diaphragms into place.

The 3rd one I have that no longer works - that paddle piece (that goes between the magnets that the diaphragms attach to) wore into the coil so bad the coil is open now, so plug it in and it does nothing.

I have another that failed the same way but was able to get it rebuilt before it wore through the coil. Still got rusty iron crap all over everything.

I'm done with these pumps. Never know when the stupid things are going to take a crap. I recently replaced one with a jehmco 60 LPM and much to my surprise I couldn't really tell a difference, which is pretty messed up beings the specs are so different. That Jehmco is LESS the HALF the size. I can't help but think the pondmasters are over rated.

 

[davenmandy]

Good info, thank you. Good idea to pop the top off and shim it, cuz if you don't there is no way to shim it as you put it on. I didn't want to mess with it so I didn't take that top part off. I am going to be running a 7" round aluminum oxide air stone off this same pump soon for a reactor on another system so that should help if it is being restricted. With the way it boils the current reactor I would hate to see it full blast if it is restricted lol.