| Author | Message | ||
| ChuckMC9 (Chucks)
Rating: N/A |
This question might not appear conversion-related, but it is! So, this is an idiot check...if you have a marine bilge pump at the bottom of a pan which pumps 360gph thru a 3/4 piece o' pipe, it should suck up water at more than an adequate rate if you have a 2.8gpm input into the pan, right? As I figure from these rocket science calculations, the pump has about twice the capacity of the water flowing in. Do bilge pumps complain if they're sucking air some of the time? Does it hurt to run them without anything to pump for X amount of time? | ||
| Geoff (Geoff)
Rating: N/A |
Bilge pumps normally have a float/switch to turn them on and off. I'm not sure what you are thinking about setting up, but I used a marine shower sump pump that comes in a plastic box to collect and pump all my grey water into the holding tanks. Works great. | ||
| Henry R. Bergman, Jr. (Henryofcj)
Rating: N/A |
We need more exact info on this, but perhaps we, (I) can kinda answer your question. Hang on, I will try to keep it simple. 360 gpm equals 6 gallons per minute. The bilge pump will work better and transfer more stuff if it is given AT LEAST 6 gpm inflow to work with. It will pump much less if the inlet VOLUME is reduced. It can only pump what it can draft or "suck". It will also have to work harder. The higher the "head" pressure the better. That means that the deeper the water is in the pan, the better the pump will work... ...as long as the suction pipe is at the bottom of the pan. A rule of thumb is that the height of the suction pipe above the bottom of the pan... ...should not exceed the diameter of the pipe and the suction pipe should be no closer to the bottom of the pan than one half... ...the diameter of the suction pipe. As stated, your question implys that your pump will only suck what it is given, in this case only 2.8 gpm... ...as the pump CAN pump 360 gph or 6 gpm. Make sense? Sorry I am soosss wordy. Usually you can "trick" your pump in performing better... ...by inlarging the suction and discharge pipe diameter (within reason) AND by deducing or eliminating any sharp or abrupt bends, corners or joints... ...AND by placing the pump as close to the source of water to be pumped as possible...OR....if you can, place the pump BELOW the height of the pan. Bilge pumps will self prime if installed correctly and if there is a good source of water. Usually running dry for a few minutes will NOT hurt them. Yes, yes, yes....bilge pumps will quickly loose prime if they suck any real amount of air for any length of time. Again, this will vary. Sorry my answer was as clear as mud. Too many variables and lack of exact info to really help you. Good luck and let her rip!  | ||
| ChuckMC9 (Chucks)
Rating: N/A |
Aaaaaah sooooo... well it was an idiot check, because that's not what I expected. (Seems like that happens a lot lately ) I was imagining that it would 'slurp' every last bit of water regardless of level, and didn't know it needed a goodly depth of water above the inlet to do well. And really didn't expect that it's happiest when it receives more than it can handle. This is yes, for a shower, but not the final version. In the intermediate version I'm hoping to not have a drain thru the floor at all, and I'm dealing with a pretty shallow pan. Hmmm.... what I need is a water vacuum cleaner! I'm going to West Marine tomorrow and talk to them. Many thanks for your help, because I would probably have just bought one without knowing it probably isn't appropriate for this. I was surprised to learn they even have a retail store in the middle of flatland. Thought they were big boy boats only. The words marine and Dallas just don't seem to go together! | ||
| akrom Rating: N/A |
Lotsa' big lakes there boy, some big enough ta'get whitecaps when 'da wind blows. just northeast of town is on thats almost 50 miles long! Git in yore bus an go look at it. you duma** kids amaze me. akrom | ||
| ChuckMC9 (Chucks)
Rating: N/A |
I know all about these not-very-inspiring lakes. In my mind though, I don't associate Marine with bass boats and trollin' motors. | ||
| Jtng Rating: N/A |
"West Marine"? ($$$$$$) You a yuppie, or what? | ||
| FAST FRED Rating: N/A |
The flow given for most marine pumps is ar Zero head , not lifting the water , just pushing it out of the boat. On big ships the pumps are well below the waterline with their own discharge at the same level , to keep from Lifting the water . The simple Rule pump will work fine as a shower drain , but needs to be fed the water . MY Way was to sink a SS doggie bowl into the floor and glue it to the shower pan with 5200 to create the recess. A simple $10.00 ($25 at West) 360gpm does a great job of lifting shower water the 3 ft to discharge in the toilet area Senicruiser SS corner sink. This method was used as I prefer all the water tanks (fresh & Waste) inside the coach to cut down on heat requirements and winterization hassles. The Shower sump gets a dash of antifreez , which it pumps (winterizing itself ) into the sink , filling the J trap on the sink . The sink discharges into the holding tank, so all the plumbing there is protected. The Rule can run dry for the few min your showering , and its not bothered by hair ect that will choke a diaphram pump. Mostly because diaphram bilge pumps have only a 1/2 or 3/4 inlet, and small chokeably internal valves. Once you get to a 2 inch Edison almost nothing chokes it , but there $900 each and manual. The Rule 360 works for me , but I use a telephone shower head with a shut off so don't use too much water and need 10 gpm of removal. FAST FRED | ||
| ChuckMC9 (Chucks)
Rating: N/A |
Based on your feedback and further research, I've rethought the idea and will be using a bilge pump in a very different config, which will be an even better idea and solve my washroom basin dilemma at the same time. Further helpful reading, for anyone considering this... http://www.powerboat-reports.com/sample/bilge.html http://www.powerboat-reports.com/newspics/pdfs/13-6-VG.pdf http://www.powerboat-reports.com/newspics/pdfs/13-6-Lift.pdf http://www.yachtsurvey.com/bilge_pumps.htm http://www.boatus.com/boattech/casey/14.htm What starts out like a dumb question can lead to all sorts of greater insight - I'll have about 1,487 more opportunities to say *thank you* to all in the coming years. Best quote from the above? "Shut-off points are calculated to turn the pump off before it runs out of solid water and starts sounding like schoolchildren finishing their milkshakes." | ||
| DMDave Rating: N/A |
Dont forget when you use a float switch when the switch shuts off the pump the water in the hose flows back downhill into your drain box unless you use a check valve. | ||
| FAST FRED Rating: N/A |
"Dont forget when you use a float switch when the switch shuts off the pump the water in the hose flows back downhill into your drain box unless you use a check valve." This is true but for pumping shower waste the hair content will usually plug a check valve pronto. Simple cure is to either not have a float switch and just Off/ On or to raise the float so the back wash from the hose volume wont trigger the float to another cycle. FAST FRED | ||
| Henry R. Bergman, Jr. (Henryofcj)
Rating: N/A |
Hey Chucks....sorry about my murky answer. Now I understand that you want/need to have some way to drain your shower pan when in use. No problemo....you can do that. On my Crown, we are/were going to mount the pan suck pump below the level of the shower pan, then just use a $cheap$ timer switch setable to different settings or time. Let's say the shower head flows somewhere between 2 and 8 gallons per minute. I hate low flow cheap shower heads. A 6 gpm bilge or suck pump will work fine. Sosss what the water may run up over your toes. Who cares. The bilge pump will eventually clear it out. The timer prevents the pump from running dry for a long time. And...never start a paragraph with a conjunction. No...wait...what I mean is that since the pump inlet is mounted BELOW the pan height, the pump... ...will maintain prime and lift the water more than enough to get it from the shower pan to the gray tank of your choice. Yeah, you will need at least one check valve... ...to keep the water running in the correct directing and not do weird things like draining out back into the shower pan. Any good inexpensive sump pump will work. Good luck. |