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    Default CAFS Question

    We looked at a neighboring dept. new Enigine today with a rosenbaouer pump and a foam pro 2001 I think, and a CAFS. The guy that showed us the unit told us that if they were hooked to a hydrant through the six inch intake with LDH they could only run CAFS foam through one 1 3/4 inch line. He said they were told this due to the fact of the incoming hydrant pressure into the system. If they wanted to run more than one line with CAFS they would have to connect to the tank fill valve instead of direct into the pump. Any thoughts on this? Also what nozzles can you use on a foam and CAFS system. I know TFT makes a foam nozzle, but can you use a standard adjustable gallanage nozzle?

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    What kind of hydrant pressure do they have? Usually with cafs, your hydrant line goes directly to the tank, and the pump draws from the tank. How many discharges you can pump CAFS out of depends on how you speced your truck.

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    Quote Originally Posted by JSMV72 View Post
    We looked at a neighboring dept. new Enigine today with a rosenbaouer pump and a foam pro 2001 I think, and a CAFS. The guy that showed us the unit told us that if they were hooked to a hydrant through the six inch intake with LDH they could only run CAFS foam through one 1 3/4 inch line. He said they were told this due to the fact of the incoming hydrant pressure into the system. If they wanted to run more than one line with CAFS they would have to connect to the tank fill valve instead of direct into the pump. Any thoughts on this? Also what nozzles can you use on a foam and CAFS system. I know TFT makes a foam nozzle, but can you use a standard adjustable gallanage nozzle?
    This sounds like a potential problem that we and many others anticipated when spec'ing our CAFS engine. I'm guessing that they are only getting enough air for one line because the when hooked to a hydrant, their engine is running at idle or very little above. In turn, the CAFS air compressor is running too slowly to produce enough air for more than one line. We and others determined going in that in order to bring the engine speed up, we would have to work from tank during any CAFS operation.

    The solution is as you have mentioned, work from tank. That is, connect your hydrant line to a direct tank fill, if one is provided. If not, consider having one installed. We and others did this in the design and specs. We have the largest practical tank to pump line, and our main inlet includes a direct tank fill with an automatically operated tank fill valve. It is set up to maintain the tank level between 30 and 80%. It works well and we are very pleased with it.
    Last edited by chiefengineer11; 06-06-2010 at 04:43 AM.

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    Are you SURE it had Cafs? The ROSENBAUER HP(NH40) pump is capable of making a Cafs like foam but is a fixed mix system and NOT a Cafs system. Now Rosie MAKES Cafs Engines but I haven't seen one using THEIR pump. Not saying it doesn't exist but I haven't seen one. T.C.

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    Quote Originally Posted by Ledebuhr1 View Post
    What kind of hydrant pressure do they have? Usually with cafs, your hydrant line goes directly to the tank, and the pump draws from the tank. How many discharges you can pump CAFS out of depends on how you speced your truck.

    They have excellent hydrant pressure, not sure how much I would guess around 60 to 80 lbs. They have four lines plump for CAFS. And yes they found out that when running CAFS they have to hook to the tank fill line, I just did not know if this was common or if something was wrong.

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    Quote Originally Posted by Rescue101 View Post
    Are you SURE it had Cafs? The ROSENBAUER HP(NH40) pump is capable of making a Cafs like foam but is a fixed mix system and NOT a Cafs system. Now Rosie MAKES Cafs Engines but I haven't seen one using THEIR pump. Not saying it doesn't exist but I haven't seen one. T.C.
    Yep, possitve it was a CAFS system.

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    I'm by no means any kind of expert on CAFS, but I've been through a couple of demos with two of the big pump builders recently. In both cases, the rep pointed out an auto-tank fill system. It was explained to us that this was necessary to build the appropriate amount of air.

    The air compressor is driven off the pump gear box in both these systems. In order to get enough RPM for the compressor, the pump had to be running at a minimum RPM, turning the compressor at a minimum RPM. If your pump runs 50 psi at idle, and you add 60 psi of hydrant pressure, your PDP is already at 110 and where you'd pump the CAFS. Idle isn't enough RPM to push the compressor to produce the amount of air needed.

    Like I said, in both cases they had an auto-tank fill set-up. The intake had the means to provide water through a master intake valve for non-CAFS or drafting, and then a port that directed water to the tank fill and a valve automated to open it at 3/4 tank and shut down at full. This keeps the RPM on the pump/compressor and produces sufficient air for CAFS.

    If the department in questions doesn't have this set-up, I could see why they need to operate off of the tank and only had enough air for one line when off the hydrant.

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    Quote Originally Posted by JSMV72 View Post
    Yep, possitve it was a CAFS system.
    Cool.I'll have to check it out. T.C.

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    We have a Waterous Eclipse CAFS system with a 1000 GPM configuration. We only have hauled water supply in our area so we usually work from porta tanks .

    On a recent occasion we went mutual aid into town 15 miles inland and hooked up to their 12" main 85 psi residual water system. At idle I was getting 120 psi to discharge . so I had to gate back the intake to allow me to wind up the RPM's enough to spin the compressor to build the cubic foot airflow we needed to run 3 2 1/2 " attack lines with CAFS.

    We did not put an auto tank fill on when we built it back in 2000 as we rarely flow from hydrants. We don't have any in our coverage area.

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    Apparently you DO! MA IS a coverage area. hehe T.C.

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    Quote Originally Posted by JSMV72 View Post
    We looked at a neighboring dept. new Enigine today with a rosenbaouer pump and a foam pro 2001 I think, and a CAFS. The guy that showed us the unit told us that if they were hooked to a hydrant through the six inch intake with LDH they could only run CAFS foam through one 1 3/4 inch line. He said they were told this due to the fact of the incoming hydrant pressure into the system. If they wanted to run more than one line with CAFS they would have to connect to the tank fill valve instead of direct into the pump. Any thoughts on this? Also what nozzles can you use on a foam and CAFS system. I know TFT makes a foam nozzle, but can you use a standard adjustable gallanage nozzle?
    What FD. Only aware of about 3 CAFS pumper's in Iowa.

    When we were shopping Rosie responded to our RFP for tanker pumper w/CAFS with aspec for their Rosie pump and "almost like CAFS". NOT.

    Truck actually has a PTO compressor or Hale/Waterous pump with integrated compressor?

    We operate by hooking hydrant thru a direct tank fill (if the 3000gal booster tank should not be sufficient). As previous post, must have an autofill if plan to hook pump intake to a hydrant. Mfg who didn't build that way needs a kick in the butt.

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    Quote Originally Posted by neiowa View Post
    What FD. Only aware of about 3 CAFS pumper's in Iowa.

    When we were shopping Rosie responded to our RFP for tanker pumper w/CAFS with aspec for their Rosie pump and "almost like CAFS". NOT.

    Truck actually has a PTO compressor or Hale/Waterous pump with integrated compressor?

    We operate by hooking hydrant thru a direct tank fill (if the 3000gal booster tank should not be sufficient). As previous post, must have an autofill if plan to hook pump intake to a hydrant. Mfg who didn't build that way needs a kick in the butt.

    Yes, it does have a PTO drven compressor. The truck is new, only about four months old. The dept. is in NW Iowa and Cherokee Iowa has all their pumpers equiped with CAFS, but I do not know for sure how many.

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    Quote Originally Posted by Rescue101 View Post
    Apparently you DO! MA IS a coverage area. hehe T.C.
    Nah! we had to bring our CAFS pumper up town to show the boys there how to use CAFS after they broke their brand new engine after two training evolutions. The chief had the entire career + call dept on the clock for a day. He asked me to bring ours down so they didn't sit around all day waiting for theirs to be fixed. :-}

    Usually the only time we go MA to them is for tanker & Cascade truck support. Something about a career dept calling for help from us Island vollies. :-}

    Besides putting all that clean chlorinated drinking water in our tanks might cause things to start leaking + kill all the pond slunk.
    Last edited by islandfire03; 06-06-2010 at 08:25 PM.

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    Well,I heard you (or your neighbors) doing back to back "strikes" within the last 48 hrs. Both with GOOD outcomes. T.c.

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    Quote Originally Posted by Rescue101 View Post
    Well,I heard you (or your neighbors) doing back to back "strikes" within the last 48 hrs. Both with GOOD outcomes. T.c.
    That was us early yesterday. Both within a 10 minute span. That was one hull of a lightning storm. The first one only fried some low voltage lighting transformers, When we got to the second , the strike hit the ridge of the roofline & traveled down to the second floor deck and went to ground through the deck support post. It exploded and sent shrapnel over a 50 yd space. That and it blew out the cable and power.

    Sometimes ya get lucky!

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    Not trying to hi-jack the thread, or anything, but have a couple questions.

    On the three rigs we have with a CAFS, we do not have a separate intake for a tank fill, that bypasses the pump intake.

    1: Is this a good thing or a bad thing, or an omission of the build spec.

    2: Our hydrant pressure is easily over 80psi. Should this be a problem running a CAFS???

    You (neiowa) know I hate our CAFS, but I would like to get them back on line for the rigs. Is our set up part of the problem??? This is the first I've seen where you run a CAFS off the tank, and not the hydrant.

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    Quote Originally Posted by FIREMECH1 View Post
    Not trying to hi-jack the thread, or anything, but have a couple questions.

    On the three rigs we have with a CAFS, we do not have a separate intake for a tank fill, that bypasses the pump intake.

    1: Is this a good thing or a bad thing, or an omission of the build spec.

    2: Our hydrant pressure is easily over 80psi. Should this be a problem running a CAFS???

    You (neiowa) know I hate our CAFS, but I would like to get them back on line for the rigs. Is our set up part of the problem??? This is the first I've seen where you run a CAFS off the tank, and not the hydrant.

    FM1
    Here's Hale's version of the intake I spoke of... http://www.haleproducts.com/Main/Products,188,188.aspx. The rectangular part that comes out of the top of the intake (that's outside of the valve) runs to the autofill (http://www.haleproducts.com/Main/Products,175,175.aspx), which keeps the tank above 3/4. Waterous has some kind of system that does the same thing.

    It may be something that wasn't available when your rigs were built.

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    When we purchased an engine in 05 with my previous department we knew that intake pressure was going to be an issue with the CAFS system and hydrants/relays. Our solution when specing that truck was to have Hale MIV's for the intakes. With the MIVs we could gate back our intakes to regulate the pressure differential between our intake and discharge. The pressure differential was needed to allow the truck to spin with enough rpms to run the compressor, and also to provide for the heat exchanger/cooling system for the compressor. If memory serves me right we needed to maintain something like a 30 to 40psi pressure differential to allow for good flow through the heat exchanger to keep the compressor cool. If the intake with the thief direct tank fill would have been available at the time of purchasing the truck would have been a nice way to go. We opted at the time to not use a direct tank fill connection for the CAFS operations, in order to not limit the flow from the truck if things went south.

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    Quote Originally Posted by Catch22 View Post
    Here's Hale's version of the intake I spoke of... http://www.haleproducts.com/Main/Products,188,188.aspx. The rectangular part that comes out of the top of the intake (that's outside of the valve) runs to the autofill (http://www.haleproducts.com/Main/Products,175,175.aspx), which keeps the tank above 3/4. Waterous has some kind of system that does the same thing.

    It may be something that wasn't available when your rigs were built.
    The Waterous one that we have tees from the intake relief valve ahead of the master intake valve (MIV). We asked for that arrangement so as to eliminate the need of a pony inlet on that side of the engine. No matter what size supply line is brought in, and no matter what use is to be made of it, it goes to the steamer inlet. If tank water will be used, just leave the MIV closed. Water will divert to the tank fill valve. If bigger water is needed (we're long past CAFS by this time), open the MIV.

    I recall that you (Firemech) said once that you had problems with your CAFS. Was it possible that you weren't making enough air (CFM and or pressure) for it to function properly? Many systems won't do it at idle. If you're working off of an 80 psi hydrant with decent water in the ground, you're not going much, if any, above idle to supply hand lines. No engine RPM, no air. That's the logic for working from tank.

    On the subject of CAFS problems, also check your air pressure. It needs to be the same as or very slightly above the water discharge pressure. If it isn't, the air won't get into the system properly and you'll get "slug" flow. Slug flow is very annoying to anyone on the line, especially the one with the nozzle.

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    Our new CAFS engine will have a direct tank auto-fill valve installed at the left side 6" suction intake ahead of the electronic butterfly valve to address these issues when operating off a hydrant or in a relay situation. 1500gpm pump with 220 cfm compressor.

    http://www.bruinvfd.com/2932PE(4-6-10)(1).pdf
    http://www.bruinvfd.com/2932PE(4-6-10)(2).pdf

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    Our new wagon should be in soon. The one we have currently that flows CAFS has very few problems with multiple lines. We do have a higher hydrant pressure (around 60-70 lbs), and run the lines with smooth bore tips. As you can imagine we are near idle when runnin off the plug, but as far as I know we have run all of our CAFS capable lines at once. Our new engine will have the direct tank fill off the back for CAFS operations to improve the operation, and we half also purchased the TFT CAFS nozzle to try it out. I'll post how it worked in July when we place it in service
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    Quote Originally Posted by mtg55 View Post
    Our new wagon should be in soon. The one we have currently that flows CAFS has very few problems with multiple lines. We do have a higher hydrant pressure (around 60-70 lbs), and run the lines with smooth bore tips. As you can imagine we are near idle when runnin off the plug, but as far as I know we have run all of our CAFS capable lines at once. Our new engine will have the direct tank fill off the back for CAFS operations to improve the operation, and we half also purchased the TFT CAFS nozzle to try it out. I'll post how it worked in July when we place it in service
    Try the nozzle before you blow big $ on the special "CAFS" nozzle. Your local distributors can provide you with sampels. We tried TFT and Elkhart CAFS nozzles. Neither were impressive and certaily not worth the $. No improvement over a straight shutoff with removable tip and judging by the noise produced were striping bubbles out or the CAFS stream. You want something "hightech" get Akron ZerTorque nozzles as easier control of nozzle reaction.

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    Quote Originally Posted by neiowa View Post
    Try the nozzle before you blow big $ on the special "CAFS" nozzle. Your local distributors can provide you with sampels. We tried TFT and Elkhart CAFS nozzles. Neither were impressive and certaily not worth the $. No improvement over a straight shutoff with removable tip and judging by the noise produced were striping bubbles out or the CAFS stream. You want something "hightech" get Akron ZerTorque nozzles as easier control of nozzle reaction.
    Yea, tried goin the demo route first, but I convinced them just to buy one (since they "had to have them") until its field tested.
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    Quote Originally Posted by FIREMECH1 View Post
    1: Is this a good thing or a bad thing, or an omission of the build spec.
    Not an omission, its an option, and a good idea, I would not build another CAFS pumper without one.

    2: Our hydrant pressure is easily over 80psi. Should this be a problem running a CAFS???
    Only if you don't have an autofill or fail compensate. It took us a long time to learn this lesson (we had one of the first rigs in our state), we have a huge compressor (IMHO too big in fact) and at low RPM's it does not make the volume of air we need to run proper CAFS. What we do is, CAFS is made from the tank (if you have more fire than you can put out with a tank of water you should not be running CAFS), we have a Hale MIV which we use to throttle the intake and slowly refill the tank once it hits 3/4 tank.

    We were an early user of CAFS and learned a lot of lessons as did many other FD's. CAFS has gotten a bad rap by some, and early CAFS systems which were not user friendly deserve it, but a modern well built system is both easy to use and extremely effective.

    Oh, and TC, come on down and I'll put my E-1 against any of your truck for stream reach... provided you don't run pressure so high it takes 6 men to hold the line water is not going to out reach CAFS in any significant manor.
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    Quote Originally Posted by Fire304 View Post
    Not an omission, its an option, and a good idea, I would not build another CAFS pumper without one.


    Only if you don't have an autofill or fail compensate. It took us a long time to learn this lesson (we had one of the first rigs in our state), we have a huge compressor (IMHO too big in fact) and at low RPM's it does not make the volume of air we need to run proper CAFS. What we do is, CAFS is made from the tank (if you have more fire than you can put out with a tank of water you should not be running CAFS), we have a Hale MIV which we use to throttle the intake and slowly refill the tank once it hits 3/4 tank.

    We were an early user of CAFS and learned a lot of lessons as did many other FD's. CAFS has gotten a bad rap by some, and early CAFS systems which were not user friendly deserve it, but a modern well built system is both easy to use and extremely effective.
    Thanks for the input.

    The more info I read from you guys that have a good CAFS setup, I'm learning more and more the failures, or lack of knowledge of the guy that spec'd them, had.

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