Batteries die in 10 minutes

Discussion in 'Water Fed Pole Cleaning' started by WinWiz, Dec 29, 2013.

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  1. WinWiz

    WinWiz Member
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    Hi guys,

    I recently bought a Pure Freedom van-mounted system and I'm having some problems.
    Here's some of the specification:
    - Two pumps for a two-man operation
    - Fast Fill Pump
    - Two Leisure Batteries
    - 9kw Isothermal heater

    My problem is, I'm trying to use it for the first time and the system doesn't seem usable. I charge the batteries up full and it comes up as 13.2v.
    Then I activate the pump for a one-man job and the battery drops at a rate that tells me it wouldn't even last two hours.
    And if I run the fast fill pump as well (starting at 13.2v), it drops to 12.2v within 20 minutes.
    And if I try the 9kw heater (with fast fill pump off) and both pumps for a two-man job on (starting at 13.2v), it drops to 12.2v within 10 minutes.

    Have Pure Freedom fitted a non-functioning system? Or have I just been unlucky with some bad batteries? Or am I doing something wrong?
     
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  2. spruce

    spruce Grand Master
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    A fully charged leisure battery will record a voltage drop like you suggested. If you let the battery stand idle for a couple of hours you will find the battery voltage will go up a bit. I have a 110 amph leisure battery and it records 12.8v when the battery has been on charge all night.

    If I run the pump doing a few hours work, I will see that the voltage across the battery will be just below 12v. It will take about 4 hours of lying idle before a voltage reading will tell you of the battery's exact level of charge - around 12.6v.

    If you are running a split charge relay you will find that the battery will show a higher voltage when you switch the engine off, sometimes around 13.9 volts or slightly higher. It will then slowly drop.

    The Varistream we use will flash low battery at 11.5v and will kick the controller off at 10.3v as the battery is deemed flat at that voltage.

    When you decide that you are going to use the diesel heater, it has been suggested by Purefreedom that you start the heater with the van engine running before you travel to your first customer. (Obviously if you have a long way to drive then stop along the way before you reach your customer.) The vans alternator will supply the initial power needed to start the heater and it will be nice and hot for you when you start your first house. That will help preserve the charge in the battery.
     
  3. WinWiz

    WinWiz Member
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    Thanks Spruce.
    Yes I do have a split-charge relay and a diesel heater.

    Sounds like I can't rely much on the point-in-time voltage reading then?

    So are you saying that I have nothing to worry about?
    As long as I charge it every night, I'll have enough battery power for two men to work with hot water all day? And use fast-fill on site on a big commercial job? (I'd obviously plug the battery chargers on at the same time as I plug the fast fill pump in. I presume that's a good idea? The system doesn't mind having the batteries charged at the same time as the heater, fast fill & two pumps are running?)

    Also, what damage would be done to the 2 pumps, fast fill pump and heater if the batteries get too low while they are running?

    If I only fire the heater up when the van engine is running, is the van running in idle on my drive enough? Or does the alternator do a better job if the engine is being used more because it's being driven?

    Sorry for all the questions, but I don't want to wreck a new system out of ignorance and I also don't want to get caught short halfway through a big job next week.
     
  4. WinWiz

    WinWiz Member
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    And one other question: I can just about accept having to switch the engine on to spark up the heating system. But what about after that for the rest of the day? I can't leave my van running on-site while I use the hot water.
     
  5. spruce

    spruce Grand Master
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    When you have a new system then its natural to worry about things you think could be a problem. This is a typical example. You need to trust the system and use it is my recommendation.

    Purefreedom use controllers supplied by Spring and they also have low voltage cut outs. The cutout is designed to ensure that you don't kill the battery. After the Varistream we use cuts the power to the pump at 10.3v, you will find if you let the battery stand for 4 hours, it would 'recover' to about 12.1/12.2 volts.

    The controllers help to economise on power the pumps consume. At the flow we run, our Shurflo pumps use about 3.5amp per hour. So with 2 pumps running we can assume that both pumps will use about 8 amps an hour (adding about 10%.) So if you both worked for 8 hours each you would consume around 65amps. If you have a 110 amp h battery theoretically you will still have 45 amps left.

    But you will probably find that your pumps will not have run for anywhere near 8 hours. On a big commercial job we would estimate about 75% tops on the glass, residential about 50% . If that is a fair estimate, then you both would have used about 48 amps which means you still have 62 amps left in the battery.

    I have a volt and amp meter permanently connected to the leisure battery. I have found that the alternator supplies the same charge to the batteries whether the engine is idling of reving at 3000 rpm down the motorway. I run a Citroen Relay SWB but the same results were obtained when the guage was fitted to son in laws Ford Transit Connect T220 LWB.

    I have an Eberspatcher diesel air heater in my van. It draws about 13 amps for a short period when the glowplug heats up to fire the heater. It probably draws this for about 30 secs before it drops back to 2.5 amps. I believe the Webasto 9KW diesel heater draws a similar amount. The alternator will supply enough power on engine idle to start the heater without drawing any current from the leisure battery.

    I don't know how the 9kw diesel heater is setup for window cleaning. The 5kw Webasto heater is designed primarily as a block heater and will start delivering full heat until it reaches 74 degrees C when it goes onto half heat mode and switches off at 77 degrees.

    If the water temperature starts to drop when the temp reaches 74 degrees when the heater kicks into reduced heat mode, then the full heat mode will be triggered once the water temp drops to 65 degrees.
    The 9KW unit is preferred as is reduces to around 3rd heat output once full heat cycle has been achieved. This help to reduce the heater cycling (switching off and then having to start up again.)

    The trick with the diesel heater is to keep the Webasto heater running. Cycling causes battery drainage and causes the inside chamber of the heater to coke up with carbon. Webasto heaters prefer road diesel - they don't like red diesel. However a heater working for 6 hours will use around 15 amps a day. If the heater has to restart 10 times then there will be another couple of amps consumed.

    So charging both batteries every night should be more than sufficient.
     
  6. spruce

    spruce Grand Master
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    I wouldn't leave the engine running whilst working. If it get stolen then there is every possibility insurance won't cover your loss. The batteries will be able to carry the load. Starting the heater first thing will just give the batteries a head start and you will have hot water on tap (well not quite as it takes a while for the water to get through 100 meters of delivery hose.)

    My son and I had a large contract we both did off my van. Whilst the job took us about 3 hours each, we used a good 500 litres doing the job. The only time I ever had to run the engine to finish the job off was when the first leisure battery decided enough was enough. It was nearly 4 years old at that point. We have never had to run the engine since to complete a job.
     
  7. spruce

    spruce Grand Master
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    You won't do any damage to the pumps if you run them on a lower voltage. I see no problem with a battery charger working whilst the system is in operation but I would check this out with PF.

    You are right, a battery needs to rest for about 4 hours to get an accurate reading of the batteries condition and even then may not be totally accurate. (Full battery = 12.7v or higher. 75% fully charged battery = 12.5v. 50% charged = 12.4v. 25% charged = 12.2v. 12v or under = fully discharged.

    Pure Freedom should have gone through this with you in great detail whilst you were waiting around having your system fitted.

    Just get stuck in and use it. If there are any issues you find, then contact PF and ask for their advise.
     
  8. spruce

    spruce Grand Master
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    I should also have added. Your batteries will be less efficient during the winter months, but even considering this you have more than enough power in reserve.
    The current battery I have on my van is over 3 years old and I charge it every couple of days as we do minimal mileage a day - tops 10 minutes to work, 5 minutes moving van and 10 minutes drive home. At best this will put 2.5 to 3 amps back into the battery via the van's alternator.

    I don't ever recall the battery charger's guage reporting the battery below 50% charged in the 3 years its been in service even during the cold winter.

    I also should add that you should always keep your vans fuel tank above 1/4 if you are using the van's tank to supply the heater with diesel.
     
  9. WinWiz

    WinWiz Member
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    Thank you very much. You've been most helpful.

    Sorry for my ignorance.... Road Diesel? Red Diesel? What's the difference?

    The guys at PF fitted me a secondary diesel tank in the back of the van. So I don't have to worry about the 1/4 tank suggestion.

    I won't have a problem with not having hot water on tap. The guys at PF fitted me a hose splitter on the inside of the van. So while my hose reel is still in the van, instead of plugging it on to the external port, I plug it onto an internal port. Then I put the hose end back in at the top of the tank. So the water heats up and gets pushed back into the tank. That completes the circle and the entire system is warmed up. That's the theory anyway. I stopped today when the voltage dropped suddenly.

    I'll give it another go tomorrow based on the answers you gave me tonight and see if I get any further.

    I'll post the result here either way - for all the other people that might end up reading this.
     
  10. spruce

    spruce Grand Master
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    Just go out a run your system for the whole day is my advice. If the batteries don't hold out then you have a cause for complaint. If the pumps cut out due to low battery charge, then leaving the engine idling in a controller security condition will give you sufficient current to keep both pumps working to finish the day.

    Red diesel is agricultural diesel that has reduced government taxes. It is illegal to use it in road vehicles. They add red dye to it so the authorities can identify what diesel is being used if they pull you over on the side of the motorway and do a 'dip test'. However, it is perfectly legal to use it in diesel central heating systems and your Webasto heater. Farmers also use it in their farming equipment and they call it agricultural diesel.

    If you do a search on the boat forums you will find that whilst a heater works perfectly well on the water with road diesel, the same heater doesn't do well when filling up at the pump at the marina. Boats are allowed to use red diesel. There is a window cleaner is our area who has converted a hot box to wfp use and buys red diesel from a local supplier whose customers are mainly the fishing industry. The roof of this cleaners van is black with soot from his exhaust that goes through the roof and ends about 6 inches above it.

    According to Webasto the type of diesel found on Marinas was high in sulphur and a very poor grade of diesel. But it was pointed out on an earlier discussion on one of the forums that a farmer wouldn't jeopodise his million pound combine harvester by putting in a poor quality red diesel.

    Someone on one of the forums said they purchased red diesel from their Morrisons outlet, but the Morrisons garages don't sell it where we live on the North East Coast.

    One of the marine suppliers suggested that the Webasto ran well on kerosene, but this is not a recommendation supported by Webasto.
     
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