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kenny b.
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MasterPlumbers
Looking for a commercial water heater that meets school code. School code calls for
multiple operating and safety controls and multiple relief valves. We are sized now at 199,000
Btu/hr. Anything you can advise? Thanks. L.D. -
Alot of “school codes” are incompetent as the ones who write these specifications are normally morons. You are better off getting ANY commerical heater manufactured to ASME standards and asking the school authorities if THIS is APPROVED.
Now here is the real question you should be asking these DUMMIES (requesting SCHOOL CODES ) Ask these idiots IF they really have a need for a commerical water heater?
1-A commerical water heater has a
maximum warrantee of 3 years2- A commmerical heater WILL pose a scalding problem ASK to see the FEDERAL regulations about water temperature where children are concerned ( hint 105 degree’s)
3- Unless they really have the need for VERY rapid recovery you would be better off using TWO residencial 75 Gallon heaters in lieu of one 100 Gal commerical piped in parallel this also gives (redundency)in case one tank should fail WHY put all your eggs in one basket?
4- If the IDIOTs writing these specifications REALLY have the need for the much higher water temperature, for example for sterlization for the caferteria dish washer (180 degree as per MOST health department rules in lieu of chemicals)
THEN you can be a hero and suggest putting in a hot water booster (little point of use boiler )at the dish washer.
By doing this you
1- save yourself the exposure of a child getting burned.2- Offer the “geniuses” writing the school specifications a viable option of not having to replace these commerical heaters every 3 years or so.
3- Less stand by losses as a commerical heater uses a heck of a lot of fuel.
4- The price you save on TWO residencial H/W heater more than covers the MUCH higher cost of a commerical heater.
You can install all kinds of fancy Low water cut offs and other bells and whistles as much as these folks could ever want.
The problem with most agencies (Any type of government)it is like an
INSANE ASYLUM run be the inmates.If the powers that be had ANY real talent these folks wouldnt be working for the government and they would be out producing on their own merrits not sponging off society.
I personally think the folks working for city/state /federal housing and school maintence departments are welfare subsidized as if they wernt working for the government THEY would be on welfare some place.
If you REALLY want a GREAT SAFE system get a small ASME SPEC built boiler with a hot water maker tank like Amtrol Brand.This way you have not only OPERATING controllers BUT safety controllers
PLUS you can add spill switches and low water cut offs and high temperature alarms ( to wake up the sleeping school “engineer”)Then OFFER them a NIBCO “JUST RIGHT” THAT works without a pump or electricity BUT natural stratification of the hot water molecules and causes natural circulation of the HW return.
GET everything in writing PRIOR to doing the actual work GOOD LUCK
Have a great one
SylvanLMP -
Sounds like a plan, except for a few items.
1. A residential water heater used in a nonresidential situation only has a one year warranty.
2.Regardless of whether it is commercial or residential the water temperature is controlled by the thermostat setting.
3. Residential heaters can be set to the unsafe temprature of 160 degrees for dishwashing.
4. It is difficult to pipe heaters in parallel and be sure that they will draw equally as age sets in.
5. Commercial heaters use a lot of fuel, therefore they will operate for a shorter time to reclaim the lost temperature.
5. 199m btu heaters were developed to avoid the ASME rating regulation for heaters 200m btu and over. In a school, the heater should be ASME rated regardless of the btu’s. This precludes using a residential water heater. -
wow HJ a little knowledge is a VERY dangerious thing. Instead of saying things your not sure of Possibly you could get a copy of the ASME section IV
1- Certain RESIDENCIAL manufacturers WILL give a 3 YEAR warrantee on a 10 year heater if used for commerical installations BUT you have to ask prior to installation2- Residencial H/W heaters are PRESET to a normal out put of 140-160 Degree’s UNLESS other wise requested and some are even talking about 125 DEGREES Max.
The reason “COMMERICAL” has the higher out put (water temperature) is for sterilization in COMMERICAL KITCHENS IN LIEU of chemicals (180 degrees)
I would LOVE to see you get 180 degrees out of a residencial H/W heater cause if you do YOU can make millions off the manufacturers DEFECTS
As for the ASME rating I can get a 30 GALLON ASME “RATING” if I so desired. Think about UNFIRED pressure vessels (Air tanks) some are built to ASME specifications While the cheaper models dont have any standards. Go to WW Granger catalog and look under pressure tanks ( As a Certified Low pressure boiler and unfired pressure vessel inspector and a Master Plumbers WE have to know various codes NOT just the ASME and ANY size pressure vessel CAN be made to ASME guide lines
As for piping in Parallel piping in heaters the KEY is uniformity EVERY pipe must be the same size in dia and lenth leading to the common manifold.
The bells and whistles I was talking about if you want to go into detail is simply installing a temperature gauge on the discharge line of EACH water heater and one on the common header heading up.
by having these 3 gauges you can fine tune each heater as the aqua stat may be off slightly from tank to tankIt would also be advisable to install a “heat sink” of 27″ so the hot water molecues wont travel to the cold (heat goes to cold)
Check out a Holby Mixing valve
diagrams.The origional question was “school codes” which is a crock as most school authorites have no idea about the NBBI OR GAMA or other governing bodies. The ASME only gives minimum standards and does not endorce ANY CODE or product.
As an inspector (LMP) I test according to ASME and National Board of Boiler Inspectors suggestions.
I personaly think commerical water heaters are not cost effective with all the options available today. If your talking safety and efficiency BOILERs are
the way to go. Did you know a low pressure boiler BY Code is a hot water boiler up to 160 PSI and or 250 DEGREEs YET steam is only up to 15 psi So thinking along these lines what can a commerical H/W tank offer above the safety aspect of a boiler?
SylvanLMP -
throw in the towel on this one hj, sylvan seems to be in a nasty little mood today. it almost seems like sylvan has actually met some of these “dummies” he’s refering to. i’d hate to think he’d lump folks he’s never met into the bad apple barrel. reminds me of the folks who say things like “all plumbers are ripoffs and crooks!” that really burns me up. jack
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Nah what pissed me off is “school codes” like we dont have enough regulations to learn already. ASSESTM,NBBIDA,Barrier free designs, OSHA, NFPA city ,state and national codes plus all the regulations of just running any type of business We as plumbers must know the safe water drinking act codes, pipe sizing water waste vent gas etc and here the lousy school code comes out of left field. IF the schools realy cared about anything it should be the rapid decline of the reading and math levels of the students these institutions are NOT turning out. I think what should be done is PAYING these lousy schools for PRODUCTION not more codes. Imagine US plumbing contractors putting out a “product ” like these so caled “educators” are doing. Teachers and administrators should be PAID according to the quality they can produce. Would anyone in their right mind pay a plumber who turned out the same QUALITY as these board of educations turn out?
Give me a break IF the SCHOOL codes are anything like the REST of the quality we areseeing apply for work THEN you know the “school codes” is an explosion looking for a place to happen. Have a great week end .
SylvanLMP -
I am not going to throw in the towel. In fact if I installed a non-conforming water heater and it exploded, for whatever reason, I, and my insurance company, might not even have a towel left. Regardless of personal opinions, or whatever, the code and safety regulations are the law, and you flaunt them at your own risk. If you were in NYC when the Bell building blew up, then you know that even a high tech system can be circumvented by poor servicing. A school is not the place to be practicing cost saving shortcuts.
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Sir the Telephone building explosion was possibly caused by NO relief valve (it was gagged IM told) and this pressure vessel took off like a an air filled balloon severing a gas line WHICH then caused the explosion and resulting fire
The Oklahoma school hot water HTR explosion was caused by the good ole HUMAN factor. Seems this “plumber” found the reflief valve leaking so being a good ole guy took out the relief valve plugged the opening and and drove to pick up a new one INSTEAD of taking this bomb out of service.
The pressure again built up BUT this time had no place to go and as WE both know you cant compress water ( takes tons of pressure) BUT you can compress AIR. This pressure vessel JUST exploded killing lots of children and taking out a large section of the structure. What I did say was if you had read my article was I am AGAINST commerical H/W heaters WHEN a boiler can deliver MORE H/W and comes with MUCH more Safety and Operating controlers AND can have more safeties added on as needed AND Boilers can last over 50 YEARS so pay back is realized in a short time AND boilers can be replaced easier than a HUGE heavy BULKY commerical H/W heater AND Most Boilers have the ASME/GAMA /AGA/ UL electric wiring and other ratings think about it, WHEN was the VERY last time you heard of a “boiler” explosion? Melt down possible Explosions VERY VERY VERY seldom. Reason being NO SCHOOL CODES INVOLVED DUH. Score one more for the LMP Kid. HJ dont take it personal JUST read all the codes involved in “PLUMMMMMING”
SylvanLMP -
It is PLUMBING, and why should I take it personally. A boiler lasts 50 years because it operates as a closed system. If you were to use it as a water heater, then the process of always heating fresh water will decrease its potential lifetime. And water heaters or boilers do not explode because the prerssure is building up, since the pressure will remain constant in the absence of a check valve or other backflow preventer. The explosion comes from the rupture of the vessel and the immediate release of the energy contained in the water under normal pressures.
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Sir Have you read any articles about back flow prevention? Like automatic water feeds to boilers must be protected by a back flow preventer? Today a lot of municipalities REQUIRE back flow preventers on the water main ALSO my good friend WHAT makes you think someone may come along AFTER you install a H/W tank and slap in a RPV later on as codes do change.
Never ASSUME that what you install today will not be altered OR installed and forgotten. SO in another words THE Pressure vessel MAY NOT have a place to allow for expansion on a run away firing condition. About your statement a boiler is a closed system. Does this “Closed SYSTEM” include process steam applications like a laundry OR steam washing applications?
HJ If you read about “Amtrol” products like the HOT WATER Maker that use’s A closed BOILER SYSTEM AS THE HEAT SOURCE through a coil (heat exchanger)
This has only been around sinse 1980 so the word hasnt gotten around yet huh? For your information this “hot water maker” is INDIRECT fired so this tank does not suffer the same expansion and contraction stress
(coefficient of expansion ) for the large temperature fluctions as a fired (Gas/electric/ Oil etc)vessel has. The boiler is a CLOSED system in this case But this is not to say ALL boilers are closed systems. Now HJ as for your “Closed System boilers” think about the General “HOT BOX” that heats the water going through a coil and THEN heats NEW water coming in sorry HJ NO RETURN on this “boiler” as it is a one shot deal.. did you know that a “boiler” can be made internally of copper LIKE a “Lochinvar” brand and AGAIN it is a NON return system is so desired.Having a “boiler” making hot water makes a lot of sense as
1-You have more operating controllers
2-More safety controllers
3- The actual gas fired appliance (boiler) is working under MUCH LESS Pressure ( normally less than 30 psi) a H/W heater uses street pressure PLUS expansion in the H/W tank can cause the T&P to seep AND possibly leave an air space. Think bout this fill two balloons ONE with Air one with water POP them both. Which one reacts more violently? THIS is why US professional Master Plumbers HYDRO TEST all pressure vessels not air test. Gas piping is designed for the air test and depending on local codes what the presure is. BUT the ASME testing of H/W boilers pressure vessels only talks about hydro testing pressure vessels so you dont get the violent reaction of the POP like the balloon test.
UNLESS your testing a steam boilers POP safety where you jump out all the controllers and close the king valve and fire it up and and watch for the pop safety to “pop” open and you watch the gauge to make sure your reliefing MORE steam pressure than the boiler can produce and also checking to make sure it did indeed open at no more than 15 PSI, BUT to test the actual boiler(steam) for intergrity WE still use a hydrostatic test every few years.
If you go to “plumbviews” on the top of this page your more than welcome to read my articles RE: Pressure vessels. Have a great week end.
SylvanLMP
[Edited by SylvanLMP on 09 April 2000] -
My statement was that “pressure does not cause heated vessels to explode”nd that is a fact. You can pressurize a tank until it ruptures and it will not “explode”. It will make a lot of noise when it does it, but will not destroy a building like an exploding water heater or boiler will. A “run away firing condition” can explode whether there is a backflow preventer or not. In that case the only safe situation is zero pressure, (i.e., open to the atmosphere), otherwise the system’s own pressure, (or the city supplied pressure), will create the necessary elements for an explosion.
I don’t know where you have been plumbing, but we have had indirect water heater coils since just about when boiler’s were invented. In your original reply, you did not specify an indirect coil, you implied that you would use the boiler as the water container. Now, I would like to know how you are going to purchase a boiler, heating coil, and storage tank, for less that the cost of one water heater? Ad to that the extra safety controls plus those required to ooperate the water heater, and your budget is shot. Then if you add in the fact that a boiler is about 80% efficient and then throw in the efficiency of an indirect coil, you should find that your operating costs are more with a boiler.
Expansion is linear with temperature. It does not matter whether the water is being heated directly or by a coil, it will expand the same. So if a T&P valve is going to leak on a water heater, it is also going to heat on your storage tank, or are you not going to install a T&P valve on the storage tank? If not, shame on you. And where is the air going to come from if a T&P pops? Have the physics somehow become reversed so that air can enter a vessel when the vessel is at a higher pressure? If so, then maybe all those people that say they have air in their pipes are correct. Maybe air is sneaking into their pipes from loose connections and cracks. Your balloon analogy is parially correct, but a pressure vessel that is overfired and then ruptures is more violent, by a factor of hundreds, than one that ruptures under air presssure.
And why should I wish to read your articles on “pressure vessels”, when I have already read articles by professionals in the trade? And I have been reading them since the 50’s. You know back when the Southern states were not requiring T&P valves because water heaters wtih their ECO “were as safe as light bulbs”, and they were exploding every week.
Yours,
HJ (capitals this time, although I don’t really need them) -
My statement was that “pressure does not cause heated vessels to explode”nd that is a fact. You can pressurize a tank until it ruptures and it will not “explode”. It will make a lot of noise when it does it, but will not destroy a building like an exploding water heater or boiler will. A “run away firing condition” can explode whether there is a backflow preventer or not.<<<<<<<<<SNIP
OK lets take it one at a time HJ
Think about this please for one minute OK. When boiler OR pressure vessel inspectors TEST any of the above we use a “hydrostatic test”
the reason is Water cannot be compressed (takes tons of pressure in the real world get about 1% compression)Air on the other hand can be compressed LOOK AT an Oxygen bottle (tank) thousands of pounds pressure huh? Now think small this time like a pressure cooker that were popular in the 50’s did you ever hear of a phenomena called PRESSURE TEMPERATURE relationship?
As the heat goes up so does the pressure Ever see a cars window pop out in a hot summer day?
Now for your education from this NYC master. A hydronic boiler has a “{relief valve) A steam Boiler has a “Safety pop Valve” A Pressure vessel has normally a SAFETY valve.
Reason Safety Equals
AIR (generally) Like the “Safety’ on an air compressor tank. Now that we have the basics down (plumbing 101 ) we can go on to the hot water FIRED storage tankThis tank is unique in that this tank holds water BUT it can also develop an air space. Back to basics AIR can be compressed NOT water. So some genius decided to make a combination Temperature AND pressure Relief valve HENCE T&P
Did you know A low pressure boiler is one of the following either 15#
steam OR 160 POUNDS Hot water AND 260 DEGREES? Think about it.These professionals KNEW that even at 260 Degrees water wont “explode” in a closed area BUT Air can (especially if heated)
So these guys decided that a T&P should operate at 210 Degrees and only 150 PSI do us both a favor and read the fine print on the T&P box next time you install one, The ASME/GAMA/AGA/CSA spends millions of dollars for education and printing all this stuff that it appears some plumbers never bother to read OR worse yet don’t understand. Now granted running a hot water enclosed system at 260 degrees is not the best idea to do because if a pipe should rupture this super hot water will flash into steam (EXPAND NOT COMPRESS get it?) and here lies the danger my colleague.
Why don’t you do this little experiment get the BIGGEST truck inner tubes you can find? Fill one with water and stand near it and watch it plop open THEN get one and STAND as close as can and fill ER up with as much air pressure as it can hold THEN tell me IT didn’t “EXPLODE” take out heavy insurance before doing this trick.
All kidding aside you should contact GAMA and ask them to Enlighten you as to WHY hot water tanks EXPLODE. You seem like a great guy but unfortunately like a lot of plumbers have no idea of the dangers of heating a closed pressure tank. Ask your Grand mother about the old pressure cookers that if they wernt watched carefully would EXPLODE and sometimes end up killing someone. Have a great week end stay healthy and have fun…
SylvanLMP -
Let’s do another experiment. Let’s take four water heaters. We will pressurize the first with water until it ruptures, I will stand next to that one. Then we will take one with out pressure and heat it until it is boiling rapidly, and then break (rupture it), I will stand next to that one also. We will pressurize the third one to its test pressure with air and then rupture it. I will not stand next to it since it will take off like a rocket as the air excapes. Then let’s take the fourth one at city pressure and heat it to 260 degrees and then rupture it. YOU can stand next to that one. If it is inside a house, it will wind up outside what is left of the house, (and you. And there will be no comparison between what happened to the tank with air and the one with superheated hot water. If you are an “expert” on pressurized vessels then you obviously know that releasing superheated water, instantaneously, is equivalent to setting of several sticks of dynamite. I don’t have a copy of your latest posting to answer all the items in it, but it appears to be a case of if you can’t dazzle them with brilliance, then ….. Or as the preacher said, “Shaky point, shout louder.” You are grabbing at straws to try to justify your original reply, and just getting in deeper and deeper. Unless you make some other questionable statement, this is the end.
Q.E.D. -
I have been reading all the information that these plumbers are providing and trust me, Sylvan is 100% correct on all his posts. I have learned from him and am continueing to learn. One of the things I leaned years ago is “I can accept brilliance with an attitude, but ignorance with an attitude creates a double tragedy. I say. Keep us the teaching Sylvan.
Tom -
HJ in all seriousness I went to OU
Oklahoma University JUST for a low pressure boiler and un fired pressure vessel inspector course.Durning my training we fired boilers DRY and air tested tanks until they litterly exploded taking out cinder block walls. I even hydrotested tanks to over 3,000 psi with NOTHING happening but it just split open like a water balloon. As a Master plumbers we should all take the and the NFPA Courses for NFPA course (NFPA 13) Plus several PHCC code classes. Instead of having a contest and making yourself look really foolish JUST contact ANY manufacturer of your chosing and ask them HOW to test a tank Hydrostatic or air test?
Bet you a dozen donuts that you dont have the guts to contact GAMA and ask to see the video about hot water heaters. Why dont you LEARN instead of trying to make up something you know NOTHING about.
SylvanLMP -
Why don’t you contact Watts and ask to see their movie on water heaters. Then maybe you will learn something.
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and just to refresh your memory, we are not talking about TESTING pressure vessels, we are referring to what happens when their operating parameters are exceeded either intentionally or by other failures.
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p.p.s.
I know more about it than you seem to think. I have seen the results of the situation I have described, and have prevented at least two others. It is not pretty. And I am sure those conditions were not duplicated in any classroom at OU. In fact, if they were duplicated anywhere but outdoors, then the building was no longer usable. -
Well this master will agree with you hj. Sylvan is not 100% correct in my book either.Any tank of super heated water that ruptures instantly is a bomb.(super heated being 212 degrees or greater)this super heated water flashing to 1728 times its volumn in less then a blink of in eye. T&P valve use on todays water heaters is for protection in a open system where pressures will not build above street main pressure. A pressure only valve is useless under this conditions. Thus a T&P is required.
Some people make things so complicated to make themselves look better, keep it simple.
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