Service FAQ: The Most Common Firefighting Equipment Service Questions

Service FAQ: The Most Common Firefighting Equipment Service Questions
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Frequent Service Questions

Below are answers to frequent questions. Should you have one that is not answered here, please get in touch with our Support Team for prompt service.

Remote Controlled Monitors

How are the electronics configured for 12 versus 24 volt?

No configuration is required. The speed which the unit moves is based on the pulses from the encoders. As long as the voltage is above 9 volts the unit will function properly.

I see buttons marked AUX 1 and AUX 2, they don’t seem to do anything, what are they for?

There are two electronic “switches” in the motor control box that can be used to open and close valves, turn on flood lights, or for other needs of the end users by using the YE-REMAUX dual relay box.

I want to control the module from a CANBUS I/O module, is this possible?

Yes! For this purpose, TFT makes the Y4E-COMM control module. It allows for discrete inputs for each of the control functions. With a simple jumper change the TFT input module can be configured to accept either a plus 12-volt signal as a signal to move or it can be an input that is held to chassis ground.

I just want a wireless remote and the monitor, can I do that without buying other items?

Yes, the antenna is on the monitor and all that is needed is 12 or 24 volts to the monitor and the radio remote handheld and it will work. This is an ideal solution for mounting and controlling bumper turret monitors as no wires are needed from the bumper to the cab. It is also perfect for controlling aerial devices as it requires no wires to telescope down the ladder.

Monitors

How does the safety mechanism in the Blitzfire differ from that of the Crossfire?

The Blitzfire is a second-generation device. The safety valve in the Crossfire requires that the monitor lift to cause the safety valve to actuate. The Blitzfire uses a new method that senses the inertia of sliding or lifting and shuts off in response to either motion making it a safer device than even the Crossfire which was itself a major advancement.

What is the difference between the Safety Valve in the Crossfire Versus the Safety Valve in the Blitzfire?

The difference is rather dramatic. The Crossfire has a paddle that feels the ground to detect the monitor lifting. As the manual for the Crossfire cautions it is still possible for the monitor to slide. On the Blitzfire a whole new approach was taken in that we now have an inertial mechanism that detects the monitor sliding or moving and after sensing this motion it shuts the system down. The Blitzfire goes to full shutoff whereas the Crossfire shuts off 90% of the waterway.

Tactics

How do you estimate the fire flow required by room size?

A very quick, easy-to-use, and easy-to-remember formula from the National Fire Academy (NFA) can be used to estimate fire flow in a structural fire attack.

The formula is L x W /3 (Length times Width, divided by 3).

Using this formula will give you the needed water flow in gallons per minute (GPM) to darken the fire in 10 – 30 seconds when applied properly. It can also be adjusted for the percentage of involvement and if necessary, add 25% for each exposure. Here are some examples:

Example 1.
15 ft. x 20 ft. room, fully (100%) involved, no exposures.
15 x 20 = 300 sq. ft., divided by 3 = 100 GPM

Example 2.
If the room in Example 1 is only half involved, use the formula like this: 15 x 30 /3 = 100 GPM x 50% = 50 GPM.

Example 3.
If you have a structure, such as a two-car garage that is 24 x 24 that is fully involved with an exposure, the formula would go like this. (Round up the dimensions, if it will make it simpler):
25 x 25 / 3 = approx. 200 GPM. Add 50 GPM (25% of the flow rate) for the exposure = 250 GPM total.

Nozzles

Please relay the latest info on the debate concerning fog/automatic nozzles vs. smooth bore

There is no current info on the status of the debate. There have been debates in the fire service over automatic transmissions, colors of trucks, leather helmets, rubber coats, siren types, nozzle types, and wooden versus metal ladders, in each case there is eventually a winner some just take longer than others. The time factor is controlled by emotion, tradition, and availability of facts that people can see feel, and understand. The reason that the smooth bore versus fog argument has gone on for so long is that in general, a clear understanding of fire hydraulics is a thing of the past for most people. Our position which has never changed is that the water puts out the fire and we want to provide equipment that delivers that water with the most options for the firefighter.

When people compare a smooth bore against a fog nozzle they almost invariably maintain the same PUMP Pressure for the comparison. When a 50 PSi nozzle is compared against ANY nozzle even another smoothbore that is at 100 PSI it will flow more water for the same hose lay. For a given pump pressure the lower the nozzle pressure used the more pressure goes into friction loss and the higher the flow achieved. If the ONLY goal was flow then the ultimate nozzle would be a coupling itself as that flows the most water possible. The reason that does not work however is because we expect more out of a nozzle. We expect to reach, pattern control, flow control, penetration, and action out of a nozzle. What we see happening over and over is that a department lets its pump pressures gradually sink lower and lower as they encounter the “everyday” fire and even though the flow has been reduced they “get by”. Then they get a big one, the low flow doesn’t cut it, and so they put on the new-fangled low-pressure smooth bore and get results. They conclude that the NOZZLE is what increased the penetration when in fact they doubled or tripled the flow and it is the increased FLOW that did the job. Had they simply brought the throttle up on that high-performance fire truck that was bought to PUMP WATER they would have not only delivered that flow they would have also delivered it farther, with more impact, with more stream action, than a 50 PSI nozzle.

Think baseball, which pitcher hits hardest, goes the farthest and has the least amount of drop to the ball, the slow pitch or the fast pitch? The same principle applies to water which is nothing more than millions of tiny balls (droplets) being THROWN out of a nozzle. The faster they come out the farther and straighter they go before being pulled by gravity to earth. That’s the nozzle part, the tactics of when to use a straight stream and when to use a fog are yet another FAQ.

What is the correct pressure to pump a 1-3/4” hand line?

The best answer would be…it depends. The pump pressure required is going to be ENTIRELY dependent on the flow YOU want to deliver. A common error some departments make is they assume just because they change to TFT automatics and 1 3/4″ hose line, that they automatically are now delivering 200 GPM. Not so… UNLESS they are pumping the pressure (at the pump) necessary to deliver that flow. An automatic constant pressure nozzle uses the same flow hydraulics and calculations as any other type of nozzle. The main difference is that we KNOW what the nozzle pressure is going to be. Therefore, we eliminated the one variable in the equation that we did not know before. Using the standard formula of pump pressure (PP) is equal to the nozzle pressure (which we know is going to be approximately 100) plus the total amount of pressure losses due to hose size, length, elevation, device losses, etc. Because we are working with basic “fire ground 2 a.m.” type hydraulics, we can simplify the equation to be:

PP=NP+FL (FL=Hose Friction Losses) (the other losses are of less consequence)

Now it becomes a much simpler question. Let’s say we want to deliver 150 GPM through the 1 3/4″ hose line. Using a slide chart, table, hose manufacturers’ data, or other source for hose losses, we find that a flow of 150 GPM corresponds to a hose loss of about 35 psi PER 100 feet of hose. If the hose line is 150 ft. long, then we would take 1.5 times 35, or 52.5 psi. If it is 200 ft. long, then it is TIMES 2, or 70 psi hose loss.

What’s the nozzle pressure? Of course, we know it is going to be about 100 psi, so we add that to the hose loss to get our required pump pressure…. for 150 GPM…

150 ft. = 150 psi pump pressure
200 ft. = 170 psi pump pressure

(note: I typically round all calculated numbers to the nearest 10 PSI. There are so many variations in hose types, and interior finishes that to “split hairs” any further is simply not practical on the fire ground. In a classroom maybe, but when pressure gauges typically flutter and bounce 5-10 psi, what is the point of trying to obtain 152.50 psi?

Finally, what happens when we have the same 150 ft. reconnect and we increase the pump pressure to 200 PSI? Since the nozzle pressure remains constant, we now have 100 psi for hose loss. Divide by 1.5 and we get the loss per 100 feet or 66 psi. Again referring to your hose friction loss chart, this equals a flow rate of 200 GPM.

If you are using a Mid Force Dual pressure nozzle, rather than a single pressure nozzle, the nozzle operating pressure should be substituted. This is the reason that with the same hose length and pump pressure, the Mid Force will deliver more actual GPM because there is about 30 psi (100-70) additional pressure which is used to overcome additional hose losses.

For additional information on calculating flows and pressures with automatic nozzles, refer to TFT publication LTT-010, “A Guide to Automatic Nozzles” available here on the TFT website, or available free of charge by calling 1-800-348-2686 [email protected].

What is the correct pressure to pump to a TFT hand line?

The pump pressure you choose is based on the size of the hose and what you want to flow. In the post that opened this thread, there is a comment about 100 PSI at the nozzle versus 200 PSI at the nozzle. Not so!! An automatic nozzle BY DEFINITION maintains a CONSTANT pressure at the nozzle.

Think of the nozzle as a screen door with a spring. If the wind is light the screen door does not blow open. As soon as there is enough wind to overcome the force of the spring on the door it starts to move and let some of the air go around the screen. The harder the wind blows the more the door opens but the FORCE against the door is constant as set by the spring. The automatic nozzle is the same thing. It has a spring and it maintains a constant pressure if the wind blows harder (higher pump pressure) more wind goes through the door opening (around the door. If the pump pressure is INCREASED the nozzle opens up so that the increased FLOW uses more FRICTION in the hose to eat up the increased pressure. If the pump is 150 the nozzle will set itself to a flow that allows just enough water to flow to equal 50 PSI of friction loss so that 100 is left over at the nozzle. If the pump is increased to 200 the nozzle will open more (the door swings) and it will let more water flow which increases the loss in the hose to where it equals 100 PSI. 100 at the nozzle plus 100 in loss equals 200 in that case. This is one of the neatest features of automatic nozzles, if the line needs more flow all you have to do is increase the pump pressure and you will get more flow and it happens without the operator having to set dials on the nozzle all he has to do is open the bail. There is a lot of information on this topic at the TFT website address www.tft.com. The short answer to your question would be “Determine what flow you want to start with, figure the friction loss for the hose length that you use either by using charts or by experiment, add the pressure that you come up with to 100 PSI and that is the pump pressure”

What is the ‘standard’ nozzle pressure, and what is considered to be a “low pressure” nozzle? I know that the lower pressure nozzle has lower reaction (for the same flow), but do you lose anything with a low pressure nozzle?

Standard nozzle pressure is considered by NFPA and most training manuals as 100 Pounds Per Square Inch. There is nothing magic about this number and no one seems to know where it comes from. Low-pressure nozzles are any nozzle that is designed or used at a pressure below 100 PSI. As nozzle pressures go down the stream VELOCITY or SPEED goes down. The slower the speed the less impact that the stream will have and the shorter the distance it will travel. Just as higher muzzle velocities out of a rifle allow the bullet to go farther accurately, higher nozzle pressures allow the stream to go farther as well

Large Diameter Hose Hardware

How do you adjust the relief valve on the Ball Intake Valve and how do you tell what pressure you have it set on?

There are pressures marked around the perimeter of the housing. Turn the screw in or out until the step that has the pressure you desire is flush with the face of the part that turns. Out lowers the pressure, in raises it.

Repair

Can an individual fire department send in a TFT nozzle for repair directly, or does it have to be sent in by an authorized dealer?

All TFT products can be sent directly to Task Force Tips. When sending items back for service, you MUST include a copy of the Return for Service Form. This form also lists shipping information.

How does a TFT product get sent in for repair and how long does it take to get it back?

All TFT products can be sent directly to Task Force Tips for service. When sending items back for service, you MUST include a copy of the Return for Service Form. This form also lists shipping information. Repair times vary based on our current service workload and the extent of the repairs required.

Foam

Will our TFT automatic nozzles work with the foam eductors on my department? We have 60, 95 & 125 GPM eductors, and want to use the TFT’s we use on all of our other attack lines.

The simple answer is YES without a doubt they will work. The TFT works at 100 PSI NOZZLE Pressure which is the same pressure that a manual nozzle would be at if pumped correctly. The important thing is to make SURE that the pump pressure is high enough to cover the friction loss of the eductor and the hose and still have 100 PSI left over for the nozzle. Too much is FAR better than too little. Pump it UP!! Because the educator is such a large restriction over pressuring will cause very little additional flow but it will ensure that there is enough pressure to

TFT Company Questions

What year was TFT started?

TFT was started as “Fire Task Force Innovations” in the basement of the McMillan home in Hobart Indiana in 1971. The original idea for the automatic nozzle was penned on a napkin by Clyde McMillan, that napkin is on the wall of the TFT conference room today!

Who purchased the first TFT nozzle?

Downers Grove Illinois purchased a Master Stream conversion unit in the fall of 1971. The Chief at the time was Frank Wander.