Success Story"Last summer Mark Bromann wrote in one of his columns that sprinkler success stories receive little press. Well, not too long ago, one appeared on the front cover of the Star Democrat in Easton, MD. It reported that one sprinkler activated and many lives were saved. The quote from the state fire marshal says it all: “The sprinkler put it out by the time we got there, so it did its job.”
I was gathering this and some other articles because here in Cambridge, MD, we passed a residential and beefed-up commercial sprinkler ordinance last May - apparently unbeknownst to the special interests who are now getting vocal and filling city councils heads with false and misleading information. Boo hoo.
Last fall, the city imposed a moratorium on the issue of any new permits that would be affected by the ordinance so that some re-write could take place in order to appease the landlords who suddenly can no longer afford to renovate their apartment units because they would have to provide sprinklers. Boo hoo again.
After that, they decided to hold an emergency meeting to address the moratorium. One by one, the council members indicated that they no longer supported the ordinance that they unanimously voted for several months prior and there is now talk of repealing it. They said the information provided last spring indicated minimal costs and now the NEW information indicates it costs three times that amount (the new costs were provided by the landlords, not industry professionals).
To be honest, the ordinance was poorly written: very basic, all-encompassing with little or no exceptions and, to be honest, not very realistic. I believe the Fire Marshals Association that first brought it up thought the information they provided to council would act as a baseline for developing and writing a real workable ordinance but that was never done and now we are where we are.
So anyway, we have a success story and a not-so-successful story but I will provide them with the real information and real cost data I have accumulated through the last 10 years, make a talk and hope they do the right thing. If not, maybe it will be in the 2009 ICC.
Real Cost of Wateromething is very wrong with a news story on EPA WaterSense that ran in an older issue ofPME(Nov. 2007). Rather than EPA claiming that 60 billion gallons of water costs $300 billion, it would make more sense if it cost $300 million, or about $5 per thousand gallons. Then, by claiming that the energy cost for 60 billion gallons of water is $500 million, it does not make sense that the energy cost is more than the cost of the water. Someone needs to do reality checks on what is promoted and printed. I hope that the EPA engineering is better than their claims.
Larry Spielvogel, P.E.
L. G. Spielvogel, Inc.
King of Prussia, PA
Larry is correct. Since the item ran, we’ve received a clarification from someone with the EPA WaterSense program. The item should have read: “If every home in the United States installed WaterSense-labeled faucets or faucet aerators in the bathrooms, we would save 60 billion gallons of water annually - saving households more than $350 million in water bills and about $600 million in energy costs to heat the water.” We apologize for the error.
Green Hot Water Distribution SystemsI am a mechanical engineer and have reviewed Figure 3 in your July 2008 article, “Designing Green Hot Water Distribution Systems,” which is about flow rates, pipe sizes and delivery time. I am surprised by the delivery time difference between copper, steel and CPVC piping for same size pipe. As I understand it, the delivery time is a function of flow velocity in pipe, which depends on the pipe inside diameter and flow rate. Why is the delivery time so different for the same size pipe diameters between copper, steel and CPVC piping? For example, for 1.5 gpm flow with ½-inch pipe, delivery time is 21 sec. for copper and 53 sec. for CPVC.
Fard Engineers Inc.
Gary Klein responds:
I have reviewed the figure and can understand your confusion. I would observe that the figure compares apples to oranges! It was not my intention to do this, but I must admit that I referred to work prepared by others and forgot to take the time to make the proper comparisons for piping used in comparable plumbing applications. I believe the numbers in the table are correct, but they are not the ones needed for typical residential and commercial plumbing situations.
The time to go through a given number of feet in CTS-equivalent copper, CPVC and PEX will be much closer, but not identical, as the internal diameters are slightly different. For example, one cup through copper requires 5.2 feet, through CPVC requires 6.4 feet and through PEX requires 6.6 feet. For a given flow rate, it will take 5.2/6.4 = 81% of the time to travel a given distance in CPVC and 5.2/6.6 = 79% of the time to travel a given distance in PEX.
Sewage Pump SwitchesI found Ryan Stickney’s article on “Sump and Sewage Ejector Systems” (Feb. 2008) very interesting and informative, but there is one part that I would like to see our industry re-think. All the literature I have read in the last 44 years of my career, regardless of brand, etc., shows the alarm float at being the top float of the three or four.
Our company has serviced lift stations. The standard service call is from someone in a rather advanced stage of hysteria because both pumps have now failed, the pit is full and/or overflowing, the inlet line is plugged up, and the pumps can not be pulled and/or replaced because the pit is full and the pumper truck is barely keeping up with the infall.
Next is the panic situation that both pumps have failed and, due to the utilization of an alternator, they are usually equally worn and there is now the stress of trying to find the replacement pumps immediately that will meet the correct voltage, approximate flow and head, and mount on the existing mounting rails, cables or whatever contraption they installed them on originally. That is assuming that they were correctly installed, which is not always the case.
It would be so much more logical to install the high alarm float so that it triggers between the first and second stage pump. Each pump should be sized to handle the maximum anticipated load, so the second pump should never come on unless the first stage is not performing as it should. Now, when one pump fails the alarm comes on, but there is another pump in operation that can be used to pump the pit down to facilitate access and repairs on the failed pump, and the customer still has an operational lift station.
Can this cause nuisance alarms? Yes, but rarely. We have adopted this technique and it helps keep the panic and stress level down considerably without any additional expense. It can also save quite a bit of expense by avoiding overtime labor rates and overnight freight.
I hope this is a forum to reach O.E.M.s and consultants so they will at least consider simply changing the recommended float placement. If there is an advantage to keeping the existing system, I would appreciate a simple explanation.
W. E. Estes & Son, Inc.
Ryan Stickney responds:
I would rather early alarm than not alternate. The consequences of not running a pump for long periods of time are too great.
Technically, the installing contractor can set the high level alarm in any position he would like if using mercury floats. This is one advantage to mercury floats that I failed to mention. So if you want the high level alarm to trigger between the pump one run and lag floats, then you may. With pedestal mechanical floats, you must wait for the lag pump level to trigger before you alarm. If you want to do away with nuisance alarms, a simple on delay relay is required. A PLC may be the answer for you. The possibilities are endless and they can be used with any type of float. Also, adding options in a PLC is fairly simple vs. control relay logic.
Personally, I use a PLC and a submersible level transducer and a separate float for back-up alarm for new installs and retrofits where approved for all level control. By the way, the back-up alarm can be battery-powered. Technology is great, but for commercial applications the industry is simply not ready. In municipalities, this is common with remote monitoring, so we are getting there.