1. #1
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    Question do you keep your tank to pump open??

    If you are hooked to a hydrant and flowing water do you close the tank to pump or keep it open. I have always closed mine when we are flowing water and then open it again when we are not so it will circulate. Is there a right and wrong, or just preference??

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    Normally if you leave tank to pump open once hooked to a hydrant your tank will fill and then start overflowing. Personally I normally close it. If they stop flowing water I either take a booster line and spray it in a ditch or crack the tank fill and let the tank over flow. Depending on the situation I may shut my hydrant supply and then open Tank to pump and tank fill and let the water circulate and just fill the tank as needed.

    Also depending on the amount of water you are flowing having tank to pump open can steal some of your water flow away.

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    Default Re: do you keep your tank to pump open??

    Originally posted by Svfman
    If you are hooked to a hydrant and flowing water do you close the tank to pump or keep it open. I have always closed mine when we are flowing water and then open it again when we are not so it will circulate. Is there a right and wrong, or just preference??
    Your doing it right. Boiling the water in the pump is a bad thing, recirc'ing helps to keep that from happening.

    The normal pump cooler line is small, like 5/16ths or 3/8s of an inch or so. Recircing the water through the tank fill moves it through a bigger line (at least 1.5" I think), so that keeps the pump cooler.

    You have to close it when you pump, other wise the pump will consider the tank fill as a discharge outlet and try to keep it pressured up. You really notice this with an electronic pressure governor, crack the TANK FILL and the rpms ramp up to try to keep the pressure where you set it.
    www.gvfd.org

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    Thumbs up

    If your apparatus is equiped with a check valve in the
    tank to pump line, it really won't make much difference
    if the tank to pump valve is open or closed when hooked
    to a hydrant. However if it does not have said check
    valve we keep the tank to pump valve closed when hooked
    to a water supply

    The reason many appatarus are equipted with the check valve
    is if you forget to close your tank to pump valve and are
    being supplied by L.D.H. you can blow the lid off the tank
    (saw the results of this)

    By all means keep water moving through the pump when engaged

    interested to hear your thoughts

    grenadafire@snowcrest.net
    Last edited by gfpdwh; 06-18-2004 at 01:08 PM.

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    The department I work for and volunteer for both have tank fill/recirc valves that you can open manually. If I am hooked to the hydrant and flowing water I keep the tank to pump open in case the hydrant goes dead. If the truck (most newer ones or at least in the past 20 years) have a check valve then it is not a problem, and if the hydrant dies then you have booster water to evac the boys on the line. If i am idle I usually leave a booster line in the ditch.

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    Default tank to pump open..

    Our department's SOP is that the tank to pump is to be closed when you are switching over to hydrant pressure. The feeling is that the pressure from the hydrant can rupture the tank. However, considering the size of the fill opening on the top of the rig and the intake pressure relief valve being set at 150 psi I would be very skeptical of this occuring. Our SOP also states that if this is going to be an extended operation then a booster line is opened up to keep the water and pump from overheating. I believe circulating lines w/in the pump are probably only designed for short duration ops. The one major problem we have when having to switch over from tank to hydrant is that it has to be done gradually. If you just slam the tank to pump gate in quickly and have not opened your hydrant intake completely you can lose your prime.

    Hope this helps.....

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    One question i will ask is this. If the t-p is open and flowing from hydrant, say the clapper is hung part open will it fill the tank or cause water to pull out of the tank? my thoughts are both. depending on incoming water pressure you could force feed water into the tank but on a low pressure hydrant you could actually pull water into the pump as the flow past the stuck clapper would create a venturi effect and create a suction, possibly empting the tank. just my thoughts jeff

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    I just took the state hydraulics class, and we covered this in some detail. They teach us to open the tank fill line, and close tank-to-pump when on a hydrant. Once the tank is full, close that, and hold what is in the tank for a loss of water. You can gate down the intake to reduce the pressure. As for damage to your truck tank, all the ones I have seen (not that many) have overflows, so excess water just runs out.

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    If the t-p is open and flowing from hydrant, say the clapper is hung part open will it fill the tank or cause water to pull out of the tank?
    If your water supply is not adequate or if it drops, water will be drawn from the tank if the t-p is open. Leaving the t-p open is, in a sense, an OK idea - in the case of total loss of water supply, but in the case of when the water supply drops slightly, you will be using tank water, and possibly not know it. IMO the PO should be watching the pump panel for changes, and therefore will be able to react to any prblems that arise.

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    Default You are right

    First you pull up and you start to operate off the tank? When you finally get a water supply from a source you would CLOSE the tank to pump valve. If you leave it open you will con't. to pull what water that is left in the pump out. You want to leave what water that is left in the tank in the tank for an emergency, IE: Loss of water, etc. Most pumps have a tank fill valve. To the best of my knowledge you can not fill your tank through the tank to pump valve? You probably could, but if that were the case than there would only one valve for both. Once you start to take on water from the hydrant you should steal a little water to top off your tank and then close it. There should be no worry of rupturing the tank or anything of that nature. If you are receiving to much pressure from your source, than either your Intake pressure releif valve will blow off or if another pump is supplying you, ask them to back off the pressure a little. Just a note, most tanks have a over flow valve some where low near the rear axle area, and also at the tank fill tower.

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    When hooked to a hydrant I keep my tank valve closed. If I'm not hooked to a hydrant I keep it open along with the tank fill if not operating a hand line.

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    To the best of my knowledge you can not fill your tank through the tank to pump valve?

    Yep, my exact same thought to those who are saying
    "You'll overfill your tank!"
    or
    "You'll blow the lid off your tank!"

    This is the Tank_to_Pump valve, and by neccessity it's on the suction side of the pump.

    There is the potential situation if you're hooked to a static source, there's no check valve, you're not flowing water, and the TTP is opened or leaking of backfeeding pressure to it. But if you have any discharge open, that's the end of that problem. With the size of overflows on modern tanks, I can't see anything lifting the top off of them other than a water-hammer type situation.

    The more legitimate issue you'll run into in the real-world is that the tank will present a more tempting source of water than the supply line. This is *definitely* a problem in drafting since the pump will keep wanting water out of the tank before it takes it from the suction hose. Even in hydrant ops or relay operations if you pressure drops very low on the intake, pulling suction from the tank may happen and mask for a few minutes a water supply problem till you suddenly find both collapsed suction lines and an empty tank.
    IACOJ Canine Officer
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    Originally posted by Dalmatian90
    To the best of my knowledge you can not fill your tank through the tank to pump valve?

    Yep, my exact same thought to those who are saying
    "You'll overfill your tank!"
    or
    "You'll blow the lid off your tank!"

    This is the Tank_to_Pump valve, and by neccessity it's on the suction side of the pump.

    Although it is on the suction side unless you are drafting or running with zero intake it is under pressure. Go look at some trucks from the 60's. There is no tank fill valve. You open tank to pump to fill the tank.

    As far as blowing the lid. Not likely however. I have seen the seems split on those poly tanks before. Not because of leaving the TP valve open while pumping though.

    One more thing. There's one way to find out. Try it next time you are training.

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    I remember that our old 62 front mount was set up to fill through the tank to pump line. But since that time I can not recall having to do that with any engine. Now we just use the recirc and open the tank fill lines to help keep pump cool. At least that has been how we have been intructed to do from our training classes for years, and come to think of it the manufcaturers rep say's same thing.



    STILL STANDING!!!!!!!!!!!!!!!!!!!

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    Default Re: tank to pump open..

    Originally posted by RubenL24
    Our department's SOP is that the tank to pump is to be closed when you are switching over to hydrant pressure. The feeling is that the pressure from the hydrant can rupture the tank. However, considering the size of the fill opening on the top of the rig and the intake pressure relief valve being set at 150 psi I would be very skeptical of this occuring. Our SOP also states that if this is going to be an extended operation then a booster line is opened up to keep the water and pump from overheating. I believe circulating lines w/in the pump are probably only designed for short duration ops. The one major problem we have when having to switch over from tank to hydrant is that it has to be done gradually. If you just slam the tank to pump gate in quickly and have not opened your hydrant intake completely you can lose your prime.

    Hope this helps.....
    Rupture the tank? Not if you have a tank over fill drain or a tank fill on top(never seen a tank without them). The water will release out of both. Right?

    Dave

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    Default Re: Re: tank to pump open..

    Originally posted by Dave1983


    Rupture the tank? Not if you have a tank over fill drain or a tank fill on top(never seen a tank without them). The water will release out of both. Right?

    Dave

    Dave: This particular Engine has both 6" overhead fill (unthreaded)
    and 1 1/2" overflow and yet seven 1/2" bolts across the rear top
    seam were sheared and had to be replaced.

    I can only suggest that when the tank hits full there is a
    second before the water finds the two exits (overhead fill &
    overflow) and then accelerates to the needed flow to releive
    any pressure in the tank. This is the only explanation I can
    think of.

    interested to hear your thoughts

    Bill

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    On our old 1982 Duplex/E-one we had a 750 gal aluminum tank that had a bolted on lid (the entire top of the tank was a separate piece bolted every 4 inches or so around the perimeter with a rubber gasket all the way round) it was equipted with the standard overfill tower and overflow drain tube to the ground to the rear of the rear tires. The tank also had a direct tank fill valve on the rear of the truck 2.5" valve and pipe straight into the tank. In our first due area we have several high pressure hydrants (static pressures of over 100psi are not unheard of). At least 3 times during the Engines life with us (20 years) we had a situation where the gasket was blown out of the sealing surface as the tank was filled from a high press hydrant thru the direct fill with the valve opened fully causing the tank to see some degree of pressurization when full and overflowing. Granted an unusual event but it does prove that a tank with an over fill tower and down tube can be overpressured and damaged. I doubt that you could flow enough volume and pressure thru a typical 1.5" tank fill line to cause this to happen.

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    Default Re: Re: Re: tank to pump open..

    Originally posted by gfpdwh



    Dave: This particular Engine has both 6" overhead fill (unthreaded)
    and 1 1/2" overflow and yet seven 1/2" bolts across the rear top
    seam were sheared and had to be replaced.

    I can only suggest that when the tank hits full there is a
    second before the water finds the two exits (overhead fill &
    overflow) and then accelerates to the needed flow to releive
    any pressure in the tank. This is the only explanation I can
    think of.

    interested to hear your thoughts

    Bill
    Must say, Ive never heard of it happening. My first guess would be a defect in the tank.

    Dave

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