| Author | Message | ||
| Jerry Liebler (Jerry_liebler)
Rating: |
I'm nearly ready to build my black/grey tank and I would like to include a macerator in addition to the conventional dump valve setup. This tank will be made from 3/8" polypropylene sheet and hot air welded (the grumpydog technique). Should I put a 1 1/2" valve between the macerator and the tank? Can I put the macerator on top of the tank and a pipe to the bottom thus depending on the self priming of the pump. What works and what doesn't? Regards Jerry 4107 1120 | ||
| Geoff (Geoff)
Rating: N/A |
I got a good deal on a marcerator here: http://www.rvsani-con.com/ The one I bought attaches to the 3" sewer hose, so it is not a permanent installation. Perhaps you can get some ideas on installation by looking at the various models on this website. --Geoff '82 RTS CA | ||
| Sean Welsh (Sean)
Rating: N/A |
Jerry, We plumbed our macerator to both tanks with 1.5" waste lines. I also put Valterra 1.5" gate valves in, and the macerator is off a "y" fitting downstream of the valves. Our macerator is midway up the tank wall, so depends on pump lift to get the bottom half of the tanks out. The pump will lift 5', so that's not a problem. Our tanks stretch across the width of the coach. Since the main 3" dump valves are on the street side, we put the macerator on the curb side for additional flexibility. If I had room to do it, though, I would have just plumbed it in downstream of the black and grey dump valves, but upstream of the third 3" valve that we installed just before the discharge. We also piped the macerator discharge out the bottom of the coach, to minimize the possibility of spillage in the bay. I used a full-bore 3/4" brass hose thread adapter to terminate the discharge pipe, which normally has a garden hose "cap" on it. We got a 3/4" industrial rubber hose to use with it, since we did not want to restrict the flow with a household 5/8" garden hose. I've got a photo of our setup somewhere, if you need it. -Sean | ||
| DMDave Rating: N/A |
Hey Jerry, I dont think on top of the tank is the best, but it might work depending on tank height. To get the tank empty it should be lower. Also keep in mind that you will have to take it out or apart someday and want it in a spot to do this and allow easy cleanup. Our macerator has a 1 1/2 inlet and 1" discharge hose. We havent yet run the solonoid for the tailgater discharge nozzle. | ||
| James Maxwell (Jmaxwell)
Rating: N/A |
I have always been curious as to the reasoning behind a macerator pump unit on typical RV holding tanks. Many, many yrs. ago as a pipe trades apprentice they 1st taught us that payday was on Friday and 2nd; shit runs downhill. Why the need for a pump that takes 15-20 minutes to carry-out a function that takes less than 2 minutes for gravity to do? All RV applications I have ever seen have holding tanks that are located above any hole in the ground that u might dump into. I could see a need if transfer is necessary but other than that I fail to see why anyone would go to the added work and maintenance of a macerator for dumping. Perhaps someone could enlighten me? | ||
| Sean Welsh (Sean)
Rating: N/A |
We added a macerator because we expect to spend considerable time in the boonies, where RV dumps may be few and far between. The macerator allows us to dump our tanks into a standard toilet, a pit toilet, a sewer cleanout, SSMH, or whatever. That being said, you are quite right -- using the 3" discharge by gravity is much quicker. In our case, two minutes is a bit optimistic -- five is usual. BTW, we went with a 3" discharge on the gray tank, which really speeds things up. Given how long it takes with the 3", I'm really glad we did not go with the 1.5". -Sean | ||
| Stephen Fessenden (Sffess)
Rating: N/A |
Why not tee it in to the 3" outlet of the tank? | ||
| FAST FRED Rating: N/A |
Geoff has thy right idea, Macerators need gravity feed to have any life at all. ALL are far better at chopping and Pushing waste than lifting same. The 120V units last much longer than a 12V unit hoolked even to #8 wiring on dc. As a high maint item its better installed Only when needed and the instalation is far the best where the unit can easily be rebuilt/replaced. Clip it on the 3in, as needed, and dont rely on it with out a second unit. FAST FRED | ||
| Jim (Jim_in_california)
Rating: N/A |
Speaking of these... One of the buses I'm strongly considering has typical dual 40gal waste tanks, black and gray, plumbed in the usual fashion. For boondocking, I'd like more. The bus is a Bluebird "Wanderfake". There is at present *nothing* underneath behind the rear axle, a space where there's two beefy-as-hell frame rails with nothing whatsoever between. It would be easy to hang a 100gal or even 150gal tank between those rails with it's own typical RV gravity drain 3" connector and a "garden hose" inlet in the top (plus a vent of course). Here's what I'm thinking: take the point where the existing gray and black tanks merge and put a macerator pump on. Run a section of heavy garden hose from there back over the axle and to the top of the new rear "combo" tank, which can be drained in the usual fashion. You've got potentially 40gal+40gal+150gal total waste storage, at a very low upgrade cost from where you're at now and with minimal reworking of what's in and running well now. You could run the macerator and drain one or both of the 40gal tanks only when needed into the big tank. Then run 200gal freshwater under the bed and whoa, you're in the boondocker biz now! | ||
| FAST FRED Rating: N/A |
"Then run 200gal freshwater under the bed and whoa," You may have difficulty steering with the front wheels off the ground with all tanks aft of the rear axle FULL! Whoa is right! FAST FRED | ||
| Jim (Jim_in_california)
Rating: N/A |
Nope. First, that 200gal is in ONE or the other tank only. Or put another way, it's flowing from one to the other. I know better than to have both full. Second, at present this coach weighs 23,000lb per the owner, with 11,500 of that on the front axle. That's with the 60gal diesel tank full (forward of the rear axle) and the current 40gal fresh tank full and behind the rear axle (under the back bed). 200gal of water times 8.33 is 1,666lb, nowhere near enough to unload the front end to the point of unsafe. And with care, the rig would still be drivable if I *did* have both fresh and waste tanks full. Remember, this is a front-engine flatnose "puller" bus with a diesel 504 cubic inch V8 (Cummins 504, same weight/size/power class as a Cat3208) sitting *forward* of the front axle and a Spicer 5sp just behind that. |
