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mike@fleming.cc

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Posts posted by mike@fleming.cc


  1. UPDATE on 5.7 pump mods:

    1) I added the small Shurflo accumulator tank, black ABS-type plastic, comes stated as factory filled to 20psi, w/a max pre-pressure of 40). I checked the factory pressurization & found 30psi. Since most Shurflo pumps are made for 40psi and the 5.7 is 65 psi (about 50% higher than the standard 40), I left the accumulator at 30psi or 50% higher than the advertised factory fill of 20. The accumulator smoothed out the pressure surging when cracking a faucet that I reported above. However, it did not change the actual response of the 5.7 pump, i.e. the pump spun immediately when faucet was opened, died, then restarted & ran according to the full pressure response requested at the fixture. My conclusion- the electronics are still reading the system pressure feedback the same, or else the 5.7 actuator response is acting the same regardless of what the reading of the feedback is. In either case, the accumulator is a nice addition, but doesn't fix anything about the pump working or not.

    2) My second 5.7 died in AZ while on a trip. I'm now on my 3rd 5.7 in this coach, lending credence to Shurflo's description that if there is one failure, there will be more in a given coach. The warranty in any event is fabulous; the docs state 3 years from purchase (assuming receipt) or 3 years from date of pump mfgr if no receipt. They are shipping me a new pump at this time, and I installed a spare 5.7 I bought off eBay, so will carry the warranty pump as new spare.

    3) Second pump failed while I was in the shower. Not my favorite time to interrupt & do a repair. I have an older diaphragm pump mounted where I can flex-line & wire over to it in about 20 minutes total time. So after the trip, I plumbed both the diaphragm pump & the spare 5.7 permanently on parallel lines, and put in a relay to switch over between pumps. This way I can operate off the on board tank all the time & switch between 'A' and 'B' pumps from inside the coach. I used a key fob type remote switch to power a standard Bosch type relay as an A/B switch so I didn't have to run new wiring to a permanent switch in the coach. Now I can switch pumps in the middle of a shower.


  2. These motorized reel setups (cords & hoses) fairly well max out their components in my experience. The motor can be over-amped by having the cord head or cord/hose catch on something, and the gears & motors are barely up to the task at hand. Two things I have found are useful to keeping mine running (I've had the Glendinningdrum type and the Shorelinereel setup):

    1) Clean the cord or hose when reeling in. Accumulation of dirt on the mechanisms dramatically increases friction over time and can ruin a reel setup in a few years. I have a rag handy & simply wipe down my cord as it gets sucked in.

    2) Do a hand-over-hand assist when reeling in, so the motor only has to do enough reeling to store the cord or hose, not to haul it across the ground, pull it around the power pedestal,... This minimizes strain on the components and should make for a long life. This is easy to do while I wipe down the sand, mud, etc. It is really easy to do w/the Glendinning if you use their remote control fob (you hold the cord or hose and push the fob button for retract and walk it toward the coach). You can find the remote on line for about $250 and it will handle both the cord reel and hose reel in case your rig has both.


  3. Cord flexibility is addressed by a couple of manufacturers for cords to be used in extreme cold. As a practical matter however, for replacement of a coach's 50A cord, wrestling w/the cord in the occasional freezing we get in southern climes isn't in the cards. You can get great #10 extension cords to 100 feet that will power a 20A circuit to the coach and that come in a flexible sheath/insulation material. You have to ask for a cord that is flexible to minus temps or shop on line for such.

    I have a 30A cord that is pretty flexible, and makes a great jumper in cold weather and extension when I don't need 50A (which is most of the time). I bought it at a trailer supply joint on the road somewhere. You just have to heft the particular cord & check its flexibility as these RV cords don't (as far as I know) come w/any temp ratings like professional extension cords (usually of lighter amp ratings).

    Here is a link for a 14/3 cord (way to thin for RV use of any kind except maybe a yard light) but giving an example of what to shop for.


  4. I've had the 5.7 in two coaches. First coach had a sort of stumble in the flow actuation but it was very minor, and the pump gave good service for 2 years when I traded the coach. Second coach has a pronounced stumble, where the 5.7 starts when a fixture is cracked open, it goes to near full flow for half a second, then stops altogether, then ramps up to full speed and stays w/good flow. Lots of friends w/this coach have had problems w/the 5.7, often w/multiple pump replacements. Several report that an accumulator resolves the pulsing problems (some have a constant high/low pulsing when pump is on) and pump gives great, even pressure after adding accumulator. I think the electronics are sensitive to pressure feedback, and feedback is peculiar to the coach's specific plumbing. Recently a buddy had issues new to his 5.7, and I noticed a slow drip from his 10gal water heater pressure valve; on the theory that an air gap in the heater tank would act like an accumulator, we drained the tank, replaced the pressure valve (no more leak to deplete a small air gap at top of tank), and his 5.7 works perfectly. I've fiddled w/the center adjustment screw on the impeller housing, and it changes the pulsing somewhat, but never eradicates it (there are 5 Phillips screws on the impeller head, 4 in a square that hold the head together, one in the center for adjustment of pressure sensitivity; early pumps did not have the center screw- it came in later versions of the pump). ShurFlo tech support said to turn the screw fully in (standard rotation) then back it off 1/4-1/2 turn and see if the pulsing type problems go away; no relief for me but maybe YMMV? I'll be adding a small accumulator soon to see if that eliminates the pulse. Whatever their electronic magic, the plumbing system's feedback seems like some coaches have the right type of feedback and these 5.7's never present a problem, and others can never get right w/out an accumulator.

    I like the idea of the 1000mf capacitor to reduce electronic noise; if the accumulator doesn't fix the pulsing, I'll add that also, why not- I don't have anything else to do, right?

    I put my 5.7 on a standard Bosch relay, using the coach's 3-way switch (with over 80 feet of wire so there's plenty of voltage drop) for the coil actuation on the relay, so it gets full volts direct thru a 15A fuse that comes w/the current 5.7. This is likely a major problem for many coaches, as the 3-way wire circuit is common and not every OEM uses a relay, and some who do use the 10A relay (ShurFlo recognizes this and covers it specifically in their 5.7 installation doc available on their website).

    Final thought- a water pump is pretty central to my coach usage as we run off it all the time (never on city water, because we have whole house RO). I installed a get-by pump next to the 5.7 with flex lines so I can plumb & wire over to the spare in less than 10 minutes. Only had to do that once when the original 5.7 went spin happy (ran full time, got way hot, probably melted the impeller inside the housing). Don't know what caused that, but ShurFlo warrantied the pump over the counter at a local trailer supply joint (great customer service from ShurFlow BTW). For the 2 weeks we were at Quartzite, the spare pump worked fine (noisy, and lower pressure cuz its a cheaper pump, but that's what I get for being a skin-flint). If you rely on coach's pump regularly, a spare is a good idea, and having it installed like this makes it a snap to use.


  5. Montie- I believe you have one of the 12 volt basement heaters, actuated by snap switches. The heater won't work for a number of reasons. The snap switch can go bad. If you know where the snap switch is located, you can put an ice cube on it to see if the heater kicks. Sounds like this isn't the problem as your fan runs but no heat.

    Next level of complication is inside the heater itself. IIRC there is another temp regulating device in there (maybe even another snap switch). Cheap thermo-switches are exactly that, cheap. Fortunately they are also easy to replace. Again, ice cube to check if it gets continuity on the contacts. Next is the heating element- if its fried, you will be better off w/a new heater, but before chucking the old one- strip off the spare parts you may need later like the snap switch.

    You will find more basement heater info if you go to iRV2 dot com and go to their Monaco Owner's forum and do a "search" on "basement heater." There are several threads delving into the 12V heater issues.

    Hope this helps, Mike


  6. Clog may be very simple and accessible like a mud-wasp nest in the end of the tube. Try a pipe cleaner or other type of probe to clean the tube up to the valve. You can do this while the valve is open to assist in washing the clog out (you might get a bit wet, but it will be more effective than a dry swab).


  7. Adrian- I think we've pushed the envelope on this thread, for the better. Coupla thoughts.

    I run whole house RO for my rig (not an under-sink unit), i.e. the storage tank on board is filled thru two stage filtration, then RO treatment. All water in the coach is RO water, and I run off the house pump all the time (I have a spare pump installed & ready to plumb over, and have used it once when the main pump failed). My reject water goes to the plants or to the sewer depending on best available recipient. Your admonishments about never chlorinating are good food for thought. I will rethink a regular tank & interior plumbing chlorination, even though as you note it may be I'd never have an issue. After all, chlorination is a small chore, takes maybe a relaxed hour every year or so. Good safety practice.

    As to under-sink RO units: if an RV owner is using 5 gallons out of 100 for drinking, or even 10, then the increased TDS in the holding tank shouldn't be an issue. My thinking is the tank gets filled every two to five days depending on occupant habits. So there is a periodic but regular inflow of fresh water used for showers, washing dishes, etc. that will keep the TDS to a manageable level. The only exception to this would be if somebody got on the 3 gallon per day, "sailor's rations" sort of usage for extended boondocking (i.e no refill for long periods). The TDS in the holding tank could get pretty high by the end of a ten day camping stint w/no fresh input, and the under sink unit recycling the tank contents around and around. However, the remedy I'd recommend is to take bottled water for drinking and shut off/bypass the under sink unit for extended boondocking. Whole house RO does not suffer this problem, as all water on board is good water and there is no further treatment while camping.

    A point you raised about small membrane systems is exactly why I chose to go with the larger whole house setup. Tiny membranes are good for maybe 1-2 years given conditions RV'ers present, but if you park where hardness is bad (like most of the southwest where snowbirds flock for winter, and the water tastes foul), you may be getting RO water from a small membrane within maybe 6 months that isn't really well treated. Hardness can ruin a small membrane proportionately faster than a large one. Good reason to monitor in/out quality of RO water. Also a good reason to rethink the membrane size. If you really park for extended times where water is severely hard, pre-treating w/ion-exchange softening is a consideration, but cost of that versus early retirement of a larger membrane will present cost trade-offs. Softening also requires carrying extra equipment, and recharging the resin media, which accepting a somewhat shorter life on a larger membrane omits. And of course the common misconception that softening alone takes stuff out of water needs to be dispelled; i.e. softening exchanges one kind of stuff in the water for a different, call it preferred, kind of stuff. For my money, I'd rather just take the extra stuff out all together, which requires RO or distillation, and RO is way easier and more turn-key.

    Which brings the conversation to membrane sizing versus membrane rating. I have two membranes, rated at 300 gallons per day at 107 psi. Broken down to hourly, that's 12.5 gallons IF you run it at 107psi. To fill my 100 gallon tank from empty would take 8 hours at that elevated pressure, longer with lower input pressure. I've seen really small membranes stacked in pairs w/a "rated" capacity of 300GPD, but that rated flow comes at about 220psi, which the sellers don't bother to state; the real make rate is way, way lower than even 12 gallons per hour under normal conditions, maybe as low as 2 or 3GPH. In addition to the fallacious water make rating, the small size (about comparable to under-sink units which actually make only a handful of gallons per day) is subject to the hardness and other fouling we discussed above. but getting back to make rate, at 60psi, a good park pressure, you will still take nearly a full day to fill your 100 gallon tank from empty. This takes a lot of pre-planning. When I ran a 300GPD membrane at 25 psi, and 3 people taking showers in the coach each day, I needed about 16 hours of recovery time to make sure we had reserve (sometimes the water gets shut off), but that was just staying even w/3 people in the coach! If I'd had one of the 300GPD @ 220psi systems, it would not have kept up, period. Going to the so called "low pressure" 107psi rated membrane, I can make a full 100 gallons in most parks overnight without the booster pump; using the booster I can fill the tank in less than 4 hours. Now for folks that fill w/straight or filtered city water, that will take an adjustment as you are probably filling in less than an hour. But the difference in water is fabulous if the local source isn't good to start, so I gladly make the sacrifice in pre-planning water intake. If I'm partially full, and decide to pull up stakes, I start making water w/the booster pump then go about my chores to break camp (put away chairs, BBQ, mats, etc. In about an hour I've added up to 30 gallons which for us is good for 3 days if we watch consumption even a little. As you can see, lifestyle involves water use rate, and options for fill time. But with a reasonably sized RO system the shift isn't too big.

    I see you picked up on the clear filter canister problem. I see rigs w/a see-though, hose-connected canister filter sitting in direct sunlight outside the coach all the time. If I walk thru a park w/100 spaces, I'll probably see 5 of them, along w/opaque canister setups at another 10 or 15. All that warmth has to be good for something that wants to grow. Adding sunlight makes it a slam dunk that algae and other stuff will bloom.

    I never thought when I got into RV'ing that water would be such an interesting topic. Mike


  8. I've had whole house RO in my coach for 5 years, and it is the nicest thing we have added bar none. My wife loves it; never spots in the shower, faucets don't corrode, drink from any faucet any time; I can pull a bucket of rinse water for the coach or windows that will dry streak and spot free. I did the installation which was fairly easy if you have some plumbing schematics or can figure out your coach's plumbing routing. We camp in the southwest where the water is rank (>800 ppm Total Dissolved Solids), and in Mexico where it is of questionable purity and also high in TDS, and have zero issues wherever we fill up, except for what to do w/the reject water (more on that below). Got my setup from Vagabondwater.com; there are other great dealers for water products as well. Service is pretty important because each configuration has at least some variables. For whole house RO, the fill rate of your tank in an RV setting will be central to finding a good system. It will be hard to get satisfactory fill rates from any of the small membranes, regardless of manufacturer claims; I want to fill my tank and don't want to take 12 hours to do it (tho I can fill overnight the day before unplugging if I remember) because sometimes you decide you need to head out and didn't think ahead. I also have a semi-automatic control, pushing a button to start the fill cycle, with a float switch in the tank to shut it off; a latching relay opens & closes the input valving as needed to start/stop the fill cycle. If I'm boondocking for a while, I bypass the semi-auto system w/a manual valve & watch to see I've got the last 5 gallons in the tank for good measure.

    Under-sink type RO is another good alternative, but you don't get benefits all around the coach. Definitely send reject water back to the main tank if you are going to do this. I've heard some send the reject to the sewer, which is nuts.

    A couple of posts mention a minimum input pressure. Mine can fill from city pressure or I can valve over to a booster pump. I could literally fill my tank from 5 gallon buckets if needed using the booster. I have filled from city pressure down to 25psi, which is slow slow slow, but it works. North of 60 is better. My booster sends input pressure to over 100. Higher pressure runs the RO membrane both faster on thru-put, and higher in pollutant removal (I'm getting north of 97% removal of dissolved junk in the water always, 98%+ using the booster so 800 parts per million dissolved pollutants becomes less than 16ppm). I have a "comparitor gauge" that shows ppm on input water & output, so water quality is easy to check any time w/push of a button.

    Reject water from a single membrane is variable w/my system which is fairly deluxe (I dial in the desired reject %). Generically RO systems use a 1:3 ratio w/1 gallon product water to 3 gallons of input, so 2 gallons reject water. When I had a one-membrane system, I used 1:3 (33% product water) if I had a use for the reject water, and 1:2 (50-50 product to reject) if I was sending the reject water down the sewer. I have since added a second membrane which takes its feed from the first membrane's reject water. Now it is 3 in and 1.67 to the tank, 1.33 to the sewer or plant watering as applies. On our lot in AZ, I water the plants w/the reject water, which they love (our palm trees are bigger than the neighbor's which only get bubbler water when the timer waters plants. In Mexico where water is much more dear, I dial the reject rate to 50% so I get 2.25 gallons product from 3 gallons input (0.75 gallons reject).

    RO membranes degrade w/time, hardness of input water, reject % and some other input variables. If you use the standard 1:3 product to input ratio, you are washing the membrane surface at the optimal rate. Lower reject rates will trap stuff in the membrane surface and cause it to degrade faster. My membranes are 2.5"x20" or so (way larger than the under-sink type) and should last about 5 years under RV use. Like tires I expect them to die from age rather than gallonage limits. I could pre-treat for hardness while in AZ, like one post above, but because the membrane life wouldn't be affected much, I'll just send local water thru the membrane & replace as needed. Membranes are not cheap, but if they die from old age then I'm getting my best monetary efficiency out of them anyway. Under sink type membranes (and filters) come in various canister designs. FWIW I'd stay away from the proprietary designs; mfgr's change designs over time and once your replacement type is no longer available, you have to replace the system or do an interesting replumbing project rather than a drop-in replacement. Push-type PEX fitting canisters will likely be around, while proprietary spin-on types likely will change. Not that it isn't a good system, it is, but the GE Merlin setup (google) is one of those expensive element types that I expect won't be around in 5 years or will have an incompatible successor. I'd rather replace cartridges (i.e. just the membrane and filter elements) in standard config's, even if the housings cost a bit more to start. The push-type-PEX canisters are pre-fab w/housing and element inside, but have been around for some time already, so you can probably switch brands if your original supplier goes out of business. I see a lot of sleek looking proprietary canisters recently, and don't think they will be a bargain over time. Don't buy extra membranes, as they may be degraded by the time you want to swap.

    As to filters, here are some suggestions.

    1) two-stage filtration is a good compromise for RV'ing. First a sediment filter, and second a carbon block filter. 2.5" x 10" canisters make a good setup, can be plumbed together and inline from your hose connection so all city or all tank fill water gets filtered. Canisters also make a perfect system disinfection point- remove the cartridge media, add chlorine to the canister, spin it back on, then fill your tank; rinse and you are good to go. No more pouring chlorine down a hose and spilling it on yourself or clothes (or at least less spillage for the less adept). My canisters are permanently mounted in the basement for convenience. Don't buy clear housings for an exterior or lit location which will grow algae from the sunlight; opaque is better.

    2) Sediment filters: these are inexpensive to change, and should be changed every 6 months regardless of use. Stuff grows on the media as it gets trapped there and a year old filter will get kind of interesting (which is bad for your water, tho good for a grandkid who wants to learn biology and has a microscope available). Sediment filters are rated by micron level of junk removal. 5 micron is the max I'd suggest. I'm now trying some 0.5 micron cartridges which remove most cyst-type bacteria (bacteria like giardia and cryptosporidium roll into a ball and form a hard cyst shell that is impervious to chlorine, and they are very small, i.e. will pass a 1 micron filter). The cyst type bacteria are the worst and most treatment resistant germs. 0.5 micron will also trap some viruses, tho most viruses are very very small, and hopefully killed by chlorine in city water, or filtered out by soil in well water served RV parks. I use depth-wound string filter elements for sediment, but thick spun polypropylene are good also. Pleated paper filters are ridiculous; there just isn't enough media to trap much for long. Sediment elements are so cheap that going a little bit cheaper is a fools errand IMO. 5, 1 and 0.5 micron elements are easy to find and cheap to buy.

    3) Carbon filters: You will find granular carbon, and carbon block filter elements. For an RV I would not recommend any element that doesn't say carbon-BLOCK. The "block" part means the carbon was crushed and reconstituted to a block that your water must pass thru. Water can pass between and around granules of carbon and get zero filtering from it. Another, and significant issue IMO is the initial cleaning required for granular carbon- you will see some black carbon in the initial 5 or so gallons passing thru a granular carbon filter as it gets its final wash, and this carbon goes right into your system (plumbing or tank). Block type elements have little or no wash-out carbon. Usually the finer micron granular elements have more wash-out carbon, but quality of construction is a bigger variable, i.e. cheap granular filters will wash out a lot. Carbon is very aggressive in adsorbing chlorine. The carbon block element I use has 120 acres of pore surface area (that's correct, 120 acres in a 2.5x10 element) to grab chlorine and other stuff. As stated above, if you have a really good carbon-block element, you will have effectively zero chlorine in your tank. Over 5 years I had for a short while a moldy taste to the water out of one tap in the coach. Finally I used a cup of high-chlorine water (added 2 tblspn's bleach) to immerse the strainer end of the faucet, and that killed the mold and it hasn't come back. The moldy taste only happened when we didn't use the coach for a month or more, and went away after a day's use regardless. Never had a problem w/the tank, and have never disinfected the tank; I drain it when it will set for a long period. 10, 5 and 1 micron carbon block filter elements are readily available and run $15-25 each. I recommend changing them every year. Again, over time a carbon block element will trap stuff that grows on it, so yearly or less is important regardless of gallonage run thru it. For aggressive filtration- 0.5 micron sediment, then 1 micron carbon-block. I don't see much advantage to filter costs above 5 micron sediment/10 micron carbon-block. If an element doesn't say carbon-block, it is granular.

    If you want some additional reading, get The Drinking Water Book by Colin Ingram (less than $20 delivered from Amazon IIRC). The subject matter is distilled for a lay reader (i.e. don't need water chemistry or sophisticated plumbing background), quite thorough, and pretty interesting for folks like us who travel around and get water from multiple sources. I was the engineer for a local water district for a while. Sorry for the long post; hope it is useful. Mike

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