Cold Weather/Draining Pumps

[ramseycl]

All of our trucks are kept in heated bays, but some members are concerned about the pump freezing on the way to a call. We are currently debating if the pumps should be drained while in the station and reprimed after arriving on the call or left full of water while in the station.
The main argument for draining them is that it is possible that they could freeze from the time they leave the station until they get on scene. It only takes a few seconds more to reprime the pump and start delivering water. We have a large rural district and drive time can be substantial at time.
As for not draining the pumps it is the fact that people don't want to get there with no water in the pump, and have to spend time priming it.
Do any of you drain your pumps during the winter?
Anyone else deal with this, pros and cons?

[ElChup175]

This all depends...where are you at, do you normally see tempuratures below 20 degrees (cause thats when most of the problems tend to start). Another issue...what sort of vehicle are we talking about here, I have heard of ways to get around this problem with certain vehicles (one way is to turn your "aux. engine cooler" on). If your in doubt, drain it, because the extra 30 seconds it takes to reprime vs. a frozen up pump is well worth it. All it takes is one pump freeze to understand.

[42VTExplorer]

http://cms.firehouse.com/forums2/sho...threadid=65097

A (recent) winter tips thread.

Our trucks are kept in a heated bay, approximately 65 degrees, and we don't drain them. If you have extended responses in negative temperature weather, you may want to consider it. Our longest response is probably around 10 minutes, and we haven't had any problems with pumps freezing.

[firefighterox]

The main question is where is the pump? If the pump is a front mount then yes, drain and it wouldn't hurt to put a little antifreeze in it and the valves. We have mostly front mounts but we do have a new rear mount, we do put anti-freeze on all threads, nozzles and front mount pumps. With the rear-mount we were told by the manufacturer that they dont need anti-freeze as long as it is drained well.

[SpartanGuy]

All of our trucks are indoors in heated buildings at about 70 degrees. Our longest response run is maybe 4 minutes. We don't drain our pumps.

But if you have a long rural response, I'd suggest you do it.

[permaprobie]

Unless someone is there 24/7, any silly failure of your heating system can result in cracked pumps.....and take out the whole fleet.

[SpartanGuy]

Or someone could break in, or the building could collapse....


Really, if you check and maintain your heating systems regularly(like we do) and if you have people on duty 16 hours a day(like we do), there's little chance of such a 'what if' scenario.

[sdff1520]

We drain our structural engines, and one of our tenders. Brush trucks and our other tender are left wet, however the pumps are started and left running recirc. Structural engines have good pumphouse heaters, but when it gets really cold and a long response, just don't completely trust it - prefer dry pump and prime it at the incident. We did once freeze the intake pressure transducer, not a major problem, but one that needed repair, and caused a bit of confusion.

Rick

[lilyogi]

We drain all of ours.

[firefightergtp]

Not draining your pump is sub-freezing weather is just asking for trouble. Why take a chance??? Who knows whats going to happen, but guess what, we are in the "what if" business. So we have to consider that "what if" the heat decided to take a crap on a night that is below freezing. What if your engine responds and sits for a while before getting work??? It takes less than 30 seconds to prime a pump, so why take the chance?? Just my opinion.

[SpartanGuy]

Originally posted by firefightergtp
What if your engine responds and sits for a while before getting work??? It takes less than 30 seconds to prime a pump, so why take the chance??

If your engine is going to be sitting at a fire scene IN ANY SEASON and there may be some time before you begin using the pump, do what we(and most other departments in that situation would do):

1. Pull the 'tank to pump' valve.
2. Rev the pump up to get about 50-75PSI.
3. Pull the 'tank filler / pump circulator' valve.

You have just created a loop, where water comes from your tank to your pump and back to your tank. In the winter, this keeps it from freezing due to the fact that the water is moving. It also prevents you from steaming your pump b/c it keeps the impellers cool.

[jsdobson]

Bear with me, this post is a bit wordy but I think it's worth reading.

In the 18 years that I've been a firefighter in the Anchorage, Alaska area, we have not drained our pumps.

Like others have written, our apparatus are stored in a 65 degree apparatus bay and the time we spend responding to an emergency will not freeze our pumps.

If departments choose to drain their pumps, it is possible that not all water will drain from the pump and valve assemblies.

It has been our experience that "dry" or parially drained pumps will freeze faster than a "wet" pump.

Since a wet pump is a heat sink (retains warmth), we may elect to not re-circulate water from the tank through the pump. We have found that it takes nearly one hour for a wet pump to lose enough heat for freezing to be a concern. Of course, if the pump is going to sit at an emergency scene for over an hour, we will begin to re-circulate as soon as we arrive on location.

If you are going to re-circulate booster tank water through the pump, keep an eye on the temperature of the pump. Your 65 degree water is going to warm up as you re-circulate. Since your centrifugal pump is creating a partial vacuum as the impeller spins, the boiling temperature of your water is going to drop. I think this due to Boyles Law)

So....instead of protecting your pump from freezing, you now have the possibility of overheating your pump and most importantly....your pump packing. Overheat your packing and soon you will have a leaking pump.

While I might be the most northern participant in this thread (at this time), I also recognize that several of the previous posters live in states that can match the cold temps we experience up here. Ours just seems to last longer.

Dobber

[firefighterbeau]

With our rural response area being 350+ square miles driving in sub zero weather at times we drain ours. The only one that doesn't get drained is the city engine which rarely goes on a call. Only takes 30 seconds to reprime, takes weeks to get a new pump or repair the one we have, not to mention having water vs. none.

[sdff1520]

Years ago our department responded to a Coke truck on fire about 20 miles from our station. One of our pickups has a front mounted booster pump, and no one remembered to start the pump before leaving the station. When they arrived on-scene it was frozen solid.

Just a few years back we responded to a silage pit fire during sub-zero temps (-10 f if I remember correctly). It was a long incident, shuttled alot of water. Thought everything was fine until stopping by the station the following day. Four of the discharge ball valves on one of our tenders were leaking. A small amount of water gets trapped in a ball valve when its in the closed position, and it got so cold that this water froze, expanded, and ruptured the housing on the valves.

Extremely cold weather operations suck! Gloves frozen stiff, hose frozen so stiff you cant even get it back on the truck, couplings that wont come apart or thread together...anything that can go wrong will!

How warm does everyone leave their station during the freezing months? Ours is only at 45-50, maybe we should crank that up, might afford a little more time before things start to freeze.

[Dave1983]

Just wanted to take a minute to tip my helmet to all the brothers who have to deal with REAL cold weather. Cant imagine what its like t fight fire in the ice and snow.

Stay safe (and warm)

Dave

[LACAPT]

Up here in the Great White North, we drain all our pumps, take off the discahrge and intake caps, and let them sit for an hour or two. Having to drive 10-20 min to a rural call at -30C, you freeze everything that is hanging out, so you best button everything up dry . Our tanker has heated (off the rad) 4" discaharge/load ball valves on the back end. We found out the hard way a couple of years ago at a rural call with a ten min. turnaround time. Cracked both valves and had to replace.

[Rescue101]

Spartanguy,Ah NO!Last year my second dept had one of our second due pieces freeze solid.The heat plant had been serviced in Oct.It was checked(station)by the station officer Fri. nite at about 8.He went in after a weekend off on Mon and found the furnace had quit and a steamer port(not the cover,the PORT) laying on the floor.This vehicle froze SOLID in a building kept at 65f in LESS than 48 hrs.Needless to say all buildings now have MONITORED freeze alarms in them. In my primary dept we antifreeze all our pumps.Paid off in spades over the years.We've had to travel 20-30 miles or more on occasions and always been able to pump on arrival.Any water that happens to be left in the pump mixes with the antifreeze.Not everyone,particularly around here,has "manned"houses and 24 hrs at -20+ can make big differences in house temperature. T.C.

[SpartanGuy]

Rescue101:

The original poster is from Durango, CO. Average winter high: 40 degrees. Average winter low: 12

Bridgton, Maine is significantly colder, with an average high in the 20s. It's interesting to note that Bridgton achieved -28 as its record low in 1971.

Moving along: I doubt they commonly encounter anything much colder than 20s or 30s (much like Pennsylvania, for example). Nothing is going to flash freeze in the 20s, and as jsdobson, the water will retain heat.

What works for arctic/routinely subzero areas like Maine, Wisconsin, Canada, and Alaska might not be totally necessary for middle latitude locations, like Colorado, Pennsylvania, Ohio, or Oregon.

I'm not going to engage in any sort of argument with you on the subject. It boils down to the same generic statement everyone always makes: "What works for one department doesn't necessarily work for everyone else."

I can tell you that for the last 30 years, our trucks have been in heated buildings. And we've never drained our pumps. And we've never had one freeze up on us.

[Rescue101]

Hehe, I'd like to know who compiled those stats.The temps here have been down to -35f in later years than '71 and that doesn't count wind chill of which there is plenty.My point wasn't to be arguementative,just to plainly state that I have personally witnessed a perfectly good pumper be reduced to frozen scrap from 65f in LESS than 48hrs in a "insulated" fire station.A TOTAL block of ice,pump, tank,everything.A 24x24 + - block station, do the math on the heat loss/wind chill on that one.Nor do I expect others to "antifreeze"pumps,but we have for the 36+ years I've been here and it works.When our neighbors who run wet,have units get "caught",ours still work.Do we trade off in higher maintenance? Perhaps.Given choices in the cooler climes,I'd run 'em wet rather than drained.But experience shows that antifreeze works,at least for us,and as long as we can still obtain it the "tradition"will probably continue.Never been to Durango,they tell me it's nice.But cold weather ops are a 4-5 month fact of life for us so bundle up and enjoy! And kerosene "salamanders"are kinda popular at Fire scenes around here too. Happy new year to ya,and what can I agitate you on next? Hehe T.C.

[SpartanGuy]

Ok, maybe I misinterpreted your meaning. No hard feelings, then.


And the National Weather Service is where I got my stats.