Thread: CAFS Controls
11-13-2000, 09:11 PM #1Stuart CobbFirehouse.com Guest
We are spec'ing out a rear mount CAFS rescue pumper. Our local pump dealer insists that we need a separate air flow valve and pressure gauge for each discharge as well as a dual needle master discharge gauge and a air flow gauge. Are all these controls really necessary? (you all know how stupid firemen can be!)
Any of you Fallon,NV or Rattlesnake,CO guys out there (or anyone else that has some experience in this)? I like the idea of a toggle switch for wet/dry foam. Can't we keep it simple?
11-18-2000, 11:29 PM #2LHS*Firehouse.com Guest
Our rigs have a pump engage switch that also engages the CAFS, you don't need to do anything but open the hose line valves, everything is pre-set, so no yuo don't need all the controls, duplex gauges, etc
12-04-2000, 12:03 AM #3fire127797Firehouse.com Guest
Our department has just taken delivery of a SNUFFER CAFS unit. All the controls are preset. To operate the unit is just a matter of turning the unit on. Their website is www.snuffer.com Give them a look.
12-08-2000, 10:51 AM #4mike021Firehouse.com Guest
Pierce has their own CAFS system. We have their system on the new Engine we just signed for. As far as I know it is all preset and just flip a switch for on off. Do not know much about it though. Sorry
This is your brain... Pierce
This is your Brain on drugs..... E-One
12-29-2000, 10:35 PM #5FirehoseFirehouse.com Guest
Our department took delivery of a new pumper with the Waterous Eclipse CAFS pump system. After initial setup, operation is as simple as 1. engage pump, 2. open tank to pump 3. flip compressor on switch and switch to auto operation. 4. turn on foam controller 5. open discharge valve to desired flow and switch on air switch for that line. Sounds a little complicated but really isnt and is accomplished before a 100 foot preconnect can be streached.
12-31-2000, 12:20 AM #6LHS*Firehouse.com Guest
//open discharge valve to desired flow and switch on air switch for that line
So how do you aet the flow?
01-02-2001, 04:15 PM #7Capt. LouFirehouse.com Guest
HI, We've had our CAFS unit for going on 3 years. Love it! Our CAFS is a Pneumax w/200 cfm air compressor system, on a Hale 1250 gpm single stage pump with a Foam Pro proportioner. It is installed on an Eone cyclone class "A" pumper. Now the same system is available from Waterous as an all in one inclusive unit, called the "Eclipse". The biggest problem with CAFS is the installation of the system by manufacturers that don't understand CAFS and understand how "simple" it is to work it.
Engagement of the CAFS should be manually and at by the pump operator. Your SOPs should say if should be done when the pump is engaged, not the manufacturer. The number of air gauges should be limited to a main CFM gauge only. The biggest air compressor for cafs Is 200 CFMS. The average attack line flows 60 cfm, per line. A deck gun or tower monitor requires 200 cfm. A 2.5 inch handline requires 100 cfm. What I'm trying to say is you can only discharge 3 - 1 3/4 handlines, OR 1 - Deck gun, OR 1 - 2.5 & 1 - 3/4 handline. You will not have enough air for anything more than that. A dual needle gauge for air and main pump pressure is needed for synchronization of air and water pressure discharge. It is automatic. We use manual air valves to put air into the hoselines. The newer systems use electric valves. You should be concerned with your water supply piping for your CAFS unit. Because you have to raise the engines RPMs to make enough air, consideration should be given to the possibillity of working off of a "HOT" hydrant. If you are feeding you pump directly from a "HOT" hydrant, lets say 100 psi or so, your nozzle discharge pressure is going to be extremely difficult to regulate as you will be at about 1250 rpms to operate the air compressor. CAFS works best when the pump is drafting or using its booster tank.
Hope I haven't confused you to much. If you have any other questions let me know. Its easier and cheaper to change on paper than once the truck is built. The other key to CAFS is education and training of your department personnel.
01-02-2001, 06:55 PM #8LHS*Firehouse.com Guest
So how do you set the flow in real life at a fire? An earilier writter was suggesting setting the flow some how at the fire, I guess squirt water out of the nozzle and get everything set. What do you do? How do yo set flow and CFM?
We simply have everything preset. Hit the pump engage and air switch. We get perfect CAF out of all lines. No flowing, no CFMs, no pressures to worry about, fully automated. A lot of opur neighbors couldn't make CAFS unless the right guy is on shift.
///The number of air gauges should be limited to a main CFM gauge only.
Why? We don't have any and make CAFS just fine without it.
Why even have the main gauge?
//A dual needle gauge for air and main pump pressure is needed for synchronization of air and water pressure discharge.
Why do you need it? Wer don't hae one and never had any problem making great CAFS.
//We use manual air valves to put air into the hoselines.
Why have them? We don't use any and can control wet or dry or on and off.
///You should be concerned with your water supply piping for your CAFS unit.
How so and why? Isn't a 500 psi NFPA pump test enough? Heck we rarely pump over 120 psi.
///Because you have to raise the engines RPMs to make enough air, consideration should be given to the possibillity of working off of a "HOT" hydrant.
Why is that if CAFS is made at engine pressure well under 200 psi? Some FD use 100 psi. At 1200 rpm barely above idle we can supply 3 or 4 hand lines or a pair of guns or any combination. Never had an rpm or ep problem.
///If you are feeding you pump directly from a "HOT" hydrant, lets say 100 psi or so, your nozzle discharge pressure is going to be extremely difficult to regulate as you will be at about 1250 rpms to operate the air compressor.
HUH? Can't you just gate back on te dircharge handle? You do anyway to make CAFS don't you? Never had the problem you're referring to.
///CAFS works best when the pump is drafting or using its booster tank.
Why is that? Most of the time we run off hydrants. When we run off tank water or draft we see no difference. What are we missing?
01-07-2001, 01:52 PM #9FirehoseFirehouse.com Guest
Waterous uses the Foampro controller for control of the foam concentrate. Foampro has a flow meter on the discharge manifold that displays flow in GPM as well as foam concentrate used, total water flow and precentage of concentrate in the stream. For a vehicle fire, we normally flow at 40 to 60 GPM and for a structure in the 70 to 90 GPM range. GPM is set by the amount you open the valve for that discharge. To make shaving cream....flow at 10 to 15 GPM!
01-07-2001, 03:35 PM #10fireman_387Firehouse.com Guest
Thing is if your local dealer insists, insist on another dealer when what you are asking for is out there. So many times I have seen a salesman tell a dept what they wanted instead of listening and selling them what they want. As a co-owner of a fire equipment company I may suggest once to a customer if I see another view, but by all means it is my customers choice not mine in the equipment that will be right for them.
01-07-2001, 03:52 PM #11LHS*Firehouse.com Guest
How do you set the gpm for a normal fir attack, please give me all the steps. IE, pull hose, charge line, gate it back to the desired flow, open foam controler, open air valve, etc.
01-12-2001, 11:45 PM #12FirehoseFirehouse.com Guest
ON dedicated CAFS discharges, the air inlet into the discharge is just downstream of the discharge valve for that line. Air input into that line increases with increased output from the air pump and is independent of the perecent of opening of the discharge valve. Normal CAFS operation is between 2 to 1 and 3 to 1 (CFM air to GPM water/foam consentrate). The GPM reading is for the water/solution only and does not include the air. To set up for an attack on a one roomer we follow this precedure:
1. Firefighter pulls attack line and opens bail.
2. Pump operator engages pump.
3. Desired discharge is opened about 1/2 open to charge line.
4. Air compressor is engaged. (It is easier on the compressor clutch if engagement is at idle).Compressor control is switched to auto/load
5. Foam controller is turned on and switched to GPM flow. (controller default settings for Class A is 0.4% and Class B at 1%)
6. Trottle is opened to 100 PSI pump pressure.
7. with line charged and bail open the valve is adjusted to desired flow on display,for a structure in the 50 to 60 GPM range.
8.air switch for that line is turned on.
It sounds complicated but we put cafs line into operation in about 10 seconds. With a triple load or a two handled flat load it takes us about 10 seconds to pull the discharge line.
to make a drier foam, go to 4 or 5 to 1 ratio ie: 12 to 15 GPM water to 60 CFM air.
this is a too dry foam for attack but does great for protective coating of foam for adjacent structures, wildland fire and wildland interface, or to make a great snow scene for the local highschool cheerleaders picture.
We are still learning all that it will do and what works best where but I will be glad to supply anly info I can.
02-05-2001, 04:05 PM #13rm8901Firehouse.com Guest
I am interested in CAFS also, I have heard there is alot of nozzle reaction when first opening the nozzle. one more thing is it worth the money.
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