Barryd999 Posted May 17, 2012 Author Share Posted May 17, 2012 Thanks guys I agree further investigation is required. I have told this chap what you have said and he's going to try and come tomorrow and work back from the pump forwards. Link to comment Share on other sites More sharing options...
Barryd999 Posted May 17, 2012 Author Share Posted May 17, 2012 This is really doing my nut in now! Im preperation for this guy coming tomorrow I went and wired the pump back up (remember I wired it straight to the battery) I gave it a go and it started off not too bad. but I noticed after a while the noise pitch of the pump started to drop like it was struggling. Pulled the wires off and wired it directly to the battery and it was better again and didnt drop the pitch. I swapped them over a couple of times (direct to battery then wired back to the proper system) and each time the results are the same and when wired properly the pitch starts to drop. Im starting to wonder if I have a duff battery. Its probably five years old now and has had some serious hammer. On our last three week trip however we were going five days of battery then a night on hookup and everything (apart from the water pressure) seemed ok. Having said that the only other things we run of 12v is a tiny TV (Which you would not tell a drop in voltage) and the sat dish and of course the lights which seemed ok mostly LED. We cant remember if we thought the lights were dimmer than normal. The van is on hookup at the moment (it normally never is) so Im going to try it in a few hours and see what the voltage is. It was ten minutes ago reading about 12.6 (goes up to 14 when hooked up) 11.6 at the pump when wired direct and 10.6 when wired through the system. I know we are going round in circles here and your probably all sick to death of me but is there anyway of testing with this multi meter thing if the battery is knackered? Thanks again Link to comment Share on other sites More sharing options...
Guest Tracker Posted May 17, 2012 Share Posted May 17, 2012 Barryd999 - 2012-05-17 1:29 PM The van is on hookup at the moment (it normally never is) so Im going to try it in a few hours and see what the voltage is. It was ten minutes ago reading about 12.6 (goes up to 14 when hooked up) 11.6 at the pump when wired direct and 10.6 when wired through the system. I know we are going round in circles here and your probably all sick to death of me but is there anyway of testing with this multi meter thing if the battery is knackered? Thanks again Without looking back over what has already been said, does the pump run faster when the battery is on charge and showing 14.6 v which is in itself a very good charge rate and perfectly normal. 12.6 volts when fully charged and after having been left standing disconnected overnight is not too clever and would by itself suggest a somewhat tired battery as 12.7 to 12.8 volts is what a sound battery should read. .1 of a volt does not sound much but when put under load that is quickly magnified to quite possibly cause the drop at the pump which is why I wondered about how it runs with the charger on? Voltage drop is caused by very few things. Too light a thickness of cable or poor connections somewhere in the system - including any in line fuses - being about the only likely things in this case. If the van's 'system' wiring is losing you 2 volts then that does suggest there is a problem somewhere and even a one volt drop seems high to me - but I am not an expert except for surviving half a lifetime of motorhome leisure battery aggravation - so perhaps a 1 v drop is normal? The only way of getting some idea about battery condition with a multimeter is to fully charge the battery then disconnect everything from it so that there is no possible load on it, check the voltage and leave it overnight, then a few days and keep checking how well the off load voltage holds up over a week or so. It should not drop hardly at all over about a week off charge and disconnected. The only other test is a voltage 'drop' test that a battery specialist would use. This is where a very heavy current load is placed on the battery to see how it handles and recovers from a sudden high but short discharge. It's not ideal but it gives you an idea - however the problem is often that the guy doing the test also gets paid for selling you a new battery and very few batteries 'pass' the test!! When the pump is running does anything get warm? The pump, the wiring, the connections, the fuses? A warm spot in wiring represents electrical resistance and the longer it runs the warmer it gets and the more restrictive it becomes until eventually it either grinds to a halt or gets too hot to touch before either blowing a fuse or catching fire in extreme circumstances!! Can you get to the pipework? Blowing up it from pump end with the tap open gives you a good idea if it is bunged up anywhere and if you suspect non return valves have you removed, checked and cleaned it/them - or even tried the 'blow' test without it/them in situ? Blowing back down through the tap should not be possible with non return valves in place but if you can by pass them and give it a good blast that should shift any blockage? Link to comment Share on other sites More sharing options...
Barryd999 Posted May 17, 2012 Author Share Posted May 17, 2012 Tracker - 2012-05-17 2:16 PM Barryd999 - 2012-05-17 1:29 PM The van is on hookup at the moment (it normally never is) so Im going to try it in a few hours and see what the voltage is. It was ten minutes ago reading about 12.6 (goes up to 14 when hooked up) 11.6 at the pump when wired direct and 10.6 when wired through the system. I know we are going round in circles here and your probably all sick to death of me but is there anyway of testing with this multi meter thing if the battery is knackered? Thanks again Without looking back over what has already been said, does the pump run faster when the battery is on charge and showing 14.6 v which is in itself a very good charge rate and perfectly normal. 12.6 volts when fully charged and after having been left standing disconnected overnight is not too clever and would by itself suggest a somewhat tired battery as 12.7 to 12.8 volts is what a sound battery should read. .1 of a volt does not sound much but when put under load that is quickly magnified to quite possibly cause the drop at the pump which is why I wondered about how it runs with the charger on? Voltage drop is caused by very few things. Too light a thickness of cable or poor connections somewhere in the system - including any in line fuses - being about the only likely things in this case. If the van's 'system' wiring is losing you 2 volts then that does suggest there is a problem somewhere and even a one volt drop seems high to me - but I am not an expert except for surviving half a lifetime of motorhome leisure battery aggravation - so perhaps a 1 v drop is normal? The only way of getting some idea about battery condition with a multimeter is to fully charge the battery then disconnect everything from it so that there is no possible load on it, check the voltage and leave it overnight, then a few days and keep checking how well the off load voltage holds up over a week or so. It should not drop hardly at all over about a week off charge and disconnected. The only other test is a voltage 'drop' test that a battery specialist would use. This is where a very heavy current load is placed on the battery to see how it handles and recovers from a sudden high but short discharge. It's not ideal but it gives you an idea - however the problem is often that the guy doing the test also gets paid for selling you a new battery and very few batteries 'pass' the test!! When the pump is running does anything get warm? The pump, the wiring, the connections, the fuses? A warm spot in wiring represents electrical resistance and the longer it runs the warmer it gets and the more restrictive it becomes until eventually it either grinds to a halt or gets too hot to touch before either blowing a fuse or catching fire in extreme circumstances!! Can you get to the pipework? Blowing up it from pump end with the tap open gives you a good idea if it is bunged up anywhere and if you suspect non return valves have you removed, checked and cleaned it/them - or even tried the 'blow' test without it/them in situ? Blowing back down through the tap should not be possible with non return valves in place but if you can by pass them and give it a good blast that should shift any blockage? Thanks for the reply. Ill try and answer best I can Without looking back over what has already been said, does the pump run faster when the battery is on charge and showing 14.6 v which is in itself a very good charge rate and perfectly normal Not this time. It was still pretty weak When the pump is running does anything get warm? The pump, the wiring, the connections, the fuses? Dont think so but I dont even know where the fuses are. Can you get to the pipework? Blowing up it from pump end with the tap open gives you a good idea if it is bunged up anywhere and if you suspect non return valves have you removed, checked and cleaned it/them - or even tried the 'blow' test without it/them in situ? Blowing back down through the tap should not be possible with non return valves in place but if you can by pass them and give it a good blast that should shift any blockage?[/ No not tried this yet and as you say you cant blow down the taps. Actually I think you can blow down the taps when the hot tank drain is open as I sometimes do this when draining down to blow the last bit of water out. Link to comment Share on other sites More sharing options...
tonyishuk Posted May 17, 2012 Share Posted May 17, 2012 A wild suggestion ! Any possibility of removing the one way valve and back flushing the system using GENTLE mains pressure from the taps back towards the tank. (Or could use air pressure with a litle modification ?) Rgds Link to comment Share on other sites More sharing options...
Guest Tracker Posted May 17, 2012 Share Posted May 17, 2012 tonyishuk - 2012-05-17 6:44 PM A wild suggestion ! Any possibility of removing the one way valve and back flushing the system using GENTLE mains pressure from the taps back towards the tank. (Or could use air pressure with a litle modification ?) Rgds Good thinking Tony! I did exactly this (on a 1980 Bedford Dormobile Deauville)(I think) many years ago and had forgotten until Tony reminded me - but do make sure the hose is VERY secure on the tap before you turn it on! I seem to recall bypassing the pump and back flushing straight from tap to tank rather than risk damaging the pump or it's seals with mains water pressure. I can't remember why I did it but there must have been a reason other than good old fashioned curiosity! Link to comment Share on other sites More sharing options...
Barryd999 Posted May 17, 2012 Author Share Posted May 17, 2012 Thanks for the idea. Beyond my capabilities though but will suggest it to my repair man if and when he comes round! Link to comment Share on other sites More sharing options...
Brambles Posted May 17, 2012 Share Posted May 17, 2012 I shall suggest again, reason being because it is an active component apart from the motor in the pump, is check the voltage across the pressure switch with the pump running. Link to comment Share on other sites More sharing options...
Guest Tracker Posted May 17, 2012 Share Posted May 17, 2012 Brambles - 2012-05-17 8:08 PM I shall suggest again, reason being because it is an active component apart from the motor in the pump, is check the voltage across the pressure switch with the pump running. Absolutely Jon! I thought that had already been done? Link to comment Share on other sites More sharing options...
Barryd999 Posted May 17, 2012 Author Share Posted May 17, 2012 Brambles - 2012-05-17 8:08 PM I shall suggest again, reason being because it is an active component apart from the motor in the pump, is check the voltage across the pressure switch with the pump running. Ah.. Yes. I forgot that. Ill see if I can check it now Link to comment Share on other sites More sharing options...
Barryd999 Posted May 17, 2012 Author Share Posted May 17, 2012 I had to disconnect the pressure switch to test the vaults so pulled the spade connectors off while it was running and stuck the prongs of the multimeter in and it reads 12.5 which is exactly what the battery is reading. The wires at the pump which are just twisted together for now read 10. The battery was on hookup for about four hours this afternoon and read 13.3. two hours agi when I disconnected it and ran the pump for a while it read shortly after 12.7. Now a couple of hours later with it isolated it reads 12.5 Link to comment Share on other sites More sharing options...
rolandrat Posted May 17, 2012 Share Posted May 17, 2012 Barry, Think duff micro switch, they are very cheap, I think the insulation has broken down. Link to comment Share on other sites More sharing options...
Barryd999 Posted May 17, 2012 Author Share Posted May 17, 2012 rolandrat - 2012-05-17 8:36 PM Barry, Think duff micro switch, they are very cheap, I think the insulation has broken down. Are we sure my van has micro switches though? Are they actually installed in the tap? both the kitchen and bathroom taps are all effected and what about the fact that its better when the pump is directly connected to the battery? Link to comment Share on other sites More sharing options...
Brambles Posted May 17, 2012 Share Posted May 17, 2012 Arrrrgh!!! Think you have more or less told me what I was asking. I want you to test the presuure switch my measuring the volts across the two terminals when the motor is running. In other words what is the volt drop from input to switch to the output of the switch. I shall assume it is approx 12 minus 10 volts measured at pump so the pressure switch is faulty. Is it possible to directly measure the volts across the switch with it in circuit to confirm there is a volt drop when contacts are closed and prove it is faulty and not the connecting cables. Link to comment Share on other sites More sharing options...
Brambles Posted May 17, 2012 Share Posted May 17, 2012 Lets do this another way. Can you temporarily short the input and the output of the pressure switch together with a short wire. yep! you can remove the spade connetions, and stuff the short wire in the ends. Does the Pump now run faster? Link to comment Share on other sites More sharing options...
Barryd999 Posted May 17, 2012 Author Share Posted May 17, 2012 thanks. Sounds like we might be onto something. I tried to measure the voltage on the pressure switch terminals but I either couldnt get a connection (its really awkward to get at) or the voltage was zero. As soon as I pulled the connector out the pump went off. Ill have a look tomorrow when its light and see if I can figure out what you mean about bypassing it. If possible I will take some photos. I really really appreciate your help. This thing is takling over my life now! Link to comment Share on other sites More sharing options...
Derek Uzzell Posted May 18, 2012 Share Posted May 18, 2012 A water system with a submerged pump and a Whale-type pressure-sensitive switch does not need tap micro-switches to operate - in fact, fitting a Whale-type switch is a useful ploy to revive a submerged-pump system when tap micro-switches have failed. When the motorhome is put on 230V hook-up and a 12V power-feed jury-rigged between the leisure-battery and the water-pump, the water-pump will be receiving the battery-charger's full voltage of around 14V. Does this return the water pressure to the satisfactory level it was before the problem showed up? If so, then the problem has an electrical factor; if not then the fault is elsewhere. It should be anticipated that a submerged water pump that's getting 14V will run faster than if it's getting 12.5V or 10V. The pressure-sensitive switch just turns the water pump on and off according to the pressure in the water pipework. If the switch is disconnected the pump won't operate. Like the water pump, the Kon-Tiki's switch does work - though admittedly it may not be working properly. Does altering the switch's pressure-adjuster make any difference? Is it practicable to jury-rig the water supply around the pressure-sensitive switch? If so, then the switch can be removed from the equation and, if the water pump (jury-rigged to receive 14V) is able to produce good pressure at the taps, then there's a problem with the switch. What really needs to be concentrated on is the water pressure at the taps when the water system is reduced to its simplest format. If the water pump can be operated so that it feeds water directly to where the water pipework currently joins the outlet of the pressure-sensitive switch and the pressure at the taps is then OK, the system can subsequently be progressively restored to its original layout (ie. including the pressure-sensitive switch and any non-return valves) and the cause of the problem should become apparent as the other components are reinstalled. I think the low-pressure-at-taps problem persists even when the water pump is jury-rigged to receive 14V. So, even if the leisure battery needs replacement, it's not low voltage at the water pump that's causing low water pressure at the taps. I would be very wary of experimenting with water/air pressure as (presumably) a blockage shifter. This is a 1996 vehicle and needs treating with resprect. Link to comment Share on other sites More sharing options...
Barryd999 Posted May 18, 2012 Author Share Posted May 18, 2012 Thanks again Derek. I cam confirm that the pressure and flow is better when the pump is jury rigged to the battery regardless of if it's on hookup or not. Fiddling with the screw on top of the pressure switch doesn't seem to make much difference although I have noticed that particularly when it's all connected properly and you turn the tap off the pump runs on for ages. Sometimes you have to turn the screw back a tad for it to go off. It's always needed adjusting but since this problem occurred it runs on much longer. If possible I'll take some pics and maybe film it this afternoon Chap is coming on Monday morning now Link to comment Share on other sites More sharing options...
Brambles Posted May 18, 2012 Share Posted May 18, 2012 Have you tried shorting out the pressure switch yet or measuring volts across it? Link to comment Share on other sites More sharing options...
Barryd999 Posted May 18, 2012 Author Share Posted May 18, 2012 Brambles - 2012-05-18 11:22 AM Have you tried shorting out the pressure switch yet or measuring volts across it? No. I'm out at the moment but will have a go this afternoon if I can figure out what to do Link to comment Share on other sites More sharing options...
Barryd999 Posted May 18, 2012 Author Share Posted May 18, 2012 I have tried what I think Brambles has suggested and put a small wire between the two terminals on the pressure switch. It didnt make any difference though and for some reason I cannot get a voltage reading while the spades are connected but they read 12.5 vaults if I pull them off and stick the testers on them. Anyway folks. I bet this is a first. So what I have done is something I can do which is film the two tests and stick the movies and some photos on our website for you all to have a look at. I have filmed it as it is normally wired through the system and I have filmed it with the pump wired directly to the battery. The battery was reading 12.5 volts at the time. (I think it was 12.7 when I packed up yesterday) anyway here you go https://sites.google.com/site/hanktestsite2/hank-the-tank-problem-page EDIT: the pictures are quite high res so if you want more detail click on them and then click to enlarge again. Link to comment Share on other sites More sharing options...
Brambles Posted May 18, 2012 Share Posted May 18, 2012 Videos are a great help despite wahy I suggested earlier they wpudl not be. Helps a lot. Ok, we know the pressure switch contacts are not the fault. Now, might sound daft, but is your pump motor wired in reverse and is turning the wrong way. Possiibly the last pump had a fault and the new one is wired in reverse. This would explain low pressure and why the pressure switch is not operating. Now running just the positve from the battery to the pump, letting the negative return via existing wiring and see if pump runs faster. Then do the same for just the negative wire to the pump letting the positive feed through pressure switch etc. This should establish if the fault is in the positive or negative cables. An alternative would be to connect your extension lead to the battery negative. Measure the volts between the motor positive and the battery negative( ext lead) , and also measure the motor negaive lead and battery 0 volts (ext lead). This should tell us if it is teh posive or negative which is dropping the volts, or indeed both. At your pressure switch i can see you can get the probe onto the top spade, so measure the volts there betweem it and again use the extension lead on the battery zero volts terminal as a reference. All these tests with the motor running, as somwhere you have high resistance dropping volts when curremt flows. Possibly a dirty connection, fuse connection, relay, or a corroded section of cable somewhere. However even with the low volts, I think your pressure should be a lot higher. Your hot is flowing a lot slower than your cold ...what happens if you turn both hot and cold on together. Do you get a much higher flow from the taps. Check the pump polarity 1st. Even trying it reversed. Link to comment Share on other sites More sharing options...
Barryd999 Posted May 18, 2012 Author Share Posted May 18, 2012 Brambles - 2012-05-18 8:37 PM Videos are a great help despite wahy I suggested earlier they wpudl not be. Helps a lot. Ok, we know the pressure switch contacts are not the fault. Now, might sound daft, but is your pump motor wired in reverse and is turning the wrong way. Possiibly the last pump had a fault and the new one is wired in reverse. This would explain low pressure and why the pressure switch is not operating. Now running just the positve from the battery to the pump, letting the negative return via existing wiring and see if pump runs faster. Then do the same for just the negative wire to the pump letting the positive feed through pressure switch etc. This should establish if the fault is in the positive or negative cables. An alternative would be to connect your extension lead to the battery negative. Measure the volts between the motor positive and the battery negative( ext lead) , and also measure the motor negaive lead and battery 0 volts (ext lead). This should tell us if it is teh posive or negative which is dropping the volts, or indeed both. At your pressure switch i can see you can get the probe onto the top spade, so measure the volts there betweem it and again use the extension lead on the battery zero volts terminal as a reference. All these tests with the motor running, as somwhere you have high resistance dropping volts when curremt flows. Possibly a dirty connection, fuse connection, relay, or a corroded section of cable somewhere. However even with the low volts, I think your pressure should be a lot higher. Your hot is flowing a lot slower than your cold ...what happens if you turn both hot and cold on together. Do you get a much higher flow from the taps. Check the pump polarity 1st. Even trying it reversed. Thanks Ill look at this tomorrow. IF you watch the second video I turn the hot on at one point and then the cold and you do get a much higher flow so they are both coming through together ok. Mrs D says they used to be better she thinks but isnt sure. Ill try and digest what your telling me and start with turning the leads around. Link to comment Share on other sites More sharing options...
Brambles Posted May 18, 2012 Share Posted May 18, 2012 I have just had another look at vid and pics and notove the cable connecting to teh pump cable looks like quite light twin cable - bell wire!!!!! If this is quite long it could be what is dropping your volts. From the picture I would suggest it should be replaced with heavier cable not least for the protection of thicker insulation. Link to comment Share on other sites More sharing options...
Barryd999 Posted May 18, 2012 Author Share Posted May 18, 2012 Brambles - 2012-05-18 10:23 PM I have just had another look at vid and pics and notove the cable connecting to teh pump cable looks like quite light twin cable - bell wire!!!!! If this is quite long it could be what is dropping your volts. From the picture I would suggest it should be replaced with heavier cable not least for the protection of thicker insulation. Yes I thought that to. Its been in there since we got the van though. I wonder though how big a job it would be just to run new cabling from wherever it goes to the pump. this is the thing though I have no idea where it goes or ends up. Im not sure how good the guy is thats coming with electrics but will look into it. Link to comment Share on other sites More sharing options...
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