ASME Boilers

Re: ASME Boilers

PostBy: Freddy On: Tue May 13, 2008 9:34 am

If a hot water heater had a 30 PSI..... how would it hold household water pressure that usually runs 45-60 PSI? The relief valve on hot water tanks are temp/pressure, 210 degrees or 150 PSI. (pic attached) In Bar Harbor, Maine, the town gets it's water from Eagle Lake. The lake is about 200 feet higher than the town. Most people use pressure reducers because without them you have 105 PSi at the faucets. No soap need to wash your hands, just blast the dirt off!


Wasn't that mythbuster show a hoot? Wowza, it was an awesome example of the power of steam.
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Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

Re: ASME Boilers

PostBy: coalkirk On: Tue May 13, 2008 11:15 am

My bad, not enough coffe this morning.
coalkirk
 
Stoker Coal Boiler: Harman VF3000
Coal Size/Type: antrhcite/rice coal

Re: ASME Boilers

PostBy: Yanche On: Tue May 13, 2008 11:18 am

coalkirk wrote:
Freddy wrote:I woulsn't say the inspector was an idiot. I'd say he knows how to use common sense. The relief valve blows off at 20 PSI. No matter how the boiler was constructed, how much of an explosion can happen at 20 PSI?

What get's me, last I knew MA does not require a low water cut off. Maine does. Even if Maine didn't, I would have one. Especially if you have PEX tubing or any chance whatsoever of a freeze and pipe break. Without the low water cut off, if the system goes dry, it heats until meltdown, quite literally. Houses burn down because of a leaky pipe. The low water cutoff shuts the unit down if it runs dry..... actually, before it runs dry.

Pressure relief valves blow off at 30 psi unless MA requires something different tha the rest of the country.
Here's the MA code requirement.
Begin quote:
Safety Relief Valve Requirements for Hot Water Boilers. Each hot water heating boiler shall have at least one officially rated pressure relief valve set to relieve at or below the maximum allowable working pressure of the boiler. Each hot water supply boiler shall have at least one officially rated safety relief valve or at least one officially rated pressure-temperature relief valve of the automatic re-seating type set to relieve at or below the maximum allowable working pressure of the boiler. Safety relief valves officially rated as to capacity shall have pop action when tested by steam. When more than one safety relief valve is used on either hot water heating or hot water supply boilers, the additional valve or valves shall be officially rated and may be set within a range not to exceed 6 psi above the maximum allowable working pressure of the boiler up to and including 60 psi and 5% for those having a maximum allowable working pressure exceeding 60 psi. Safety relief valves shall be spring loaded. Safety relief valves shall be so arranged that they can not be reset at a higher pressure than the maximum permitted by 522 CMR 5.07.
End Quote.

I think the MA boiler code requirements are more stringent that other states because of their history. In the late 1800's and early 1900's there were many lives lost in MA because of boiler explosions. The ASME boiler code has it's origin as a result of those public safety issues.
Yanche
 
Stoker Coal Boiler: Alternate Heating Systems S-130
Coal Size/Type: Anthracite Pea

Visit Lehigh Anthracite

Re: ASME Boilers

PostBy: Yanche On: Tue May 13, 2008 11:22 am

coaledsweat wrote:
vtec350 wrote:This guys usually known for being a hard ass to deal with and doing everything by the book. Two hours later he called me and said he spoke with Jim and said that the presure relief valve is AMSE listed and he would approve it.


Lucky for you he is also an idiot. :roll:
In my opinion if the building inspector agreed to sign off on the non-ASME boiler installation because it has and ASME approved safety valve he is incompetent. If however he made the judgment after discussing the boiler vessel construction with manufacturer and was told it meets ASME design requirements he's a nice guy. Since none of us were a party to the telephone conversation we will never know.
Last edited by Yanche on Tue May 13, 2008 4:44 pm, edited 1 time in total.
Yanche
 
Stoker Coal Boiler: Alternate Heating Systems S-130
Coal Size/Type: Anthracite Pea

Re: ASME Boilers

PostBy: stoker-man On: Tue May 13, 2008 11:26 am

An efm steam boiler operates at 1 1/2 pounds of pressure; the relief valve is 15#.

Please don't invite me to the party when you're testing a boiler low on water mixed with a non-functioning relief valve. We now supply a low water cutoff with all steam boilers because most places in PA now require them. A commercial application requires two cutoffs.
stoker-man
 
Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
Coal Size/Type: Anthracite/Chestnut
Other Heating: Hearthstone wood stove

Re: ASME Boilers

PostBy: stoker-man On: Tue May 13, 2008 11:38 am

By the way, I just got the report on the church explosion in Emmaus a few years ago. I'm keeping it short. They were manually refilling the boiler because of a leak. It had been warm for a lengthy period, so it wasn't being topped off. The low-water cutoff failed and there was no high limit switch or auto-fill valve, so the boiler ran out of water, the oil burner kept firing, and the boiler got so hot that the solder joints unsweated. At or about the same time, a circulator started up and returned cold water to a 700 degree boiler (melting point of solder) and that water flashed into steam.
stoker-man
 
Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
Coal Size/Type: Anthracite/Chestnut
Other Heating: Hearthstone wood stove

Re: ASME Boilers

PostBy: Bob On: Tue May 13, 2008 1:09 pm

Freddy wrote:
Low water cut off's on 200K & larger? OK, a step in the right direction,, I wonder when they'll realize that leaves almost every home off the list. For anyone reading, they cost about $100 and are a fun electrical challange to install, but with one you get a higher level peace of mind.


Low water cut-offs also require regular testing and, usually, maintenance in order to be reliable. It is not an "install and forget" safety device.
Bob
 
Stoker Coal Boiler: AHS 130
Coal Size/Type: Pea/Anthracite

Re: ASME Boilers

PostBy: coaledsweat On: Tue May 13, 2008 1:52 pm

Yanche wrote:
coaledsweat wrote:
vtec350 wrote:This guys usually known for being a hard ass to deal with and doing everything by the book. Two hours later he called me and said he spoke with Jim and said that the presure relief valve is AMSE listed and he would approve it.


Lucky for you he is also an idiot. :roll:
In my opinion if the building inspector agreed to sign off on the non-ASME boiler installation because it has and ASME approved safety valve he is incompetent. If however he made the judgment after discussing the boiler vessel construction with manufacturer and was told it meets ASME design requirements he a nice guy. Since none of us were a party to the telephone conversation we will never know.


Thank you Yanche.

The point is even with the inspector accepting it and allowing the install it does not meet the code as written. In the event of a loss, the insurance company could care less if the Pope signed off on it. It is not to code and they do not have to pay.

vtec, pay no attention to this drivel as you will never have any problems with that unit's reliability anyway. :)
coaledsweat
 
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Re: ASME Boilers

PostBy: stoker-man On: Tue May 13, 2008 2:42 pm

From an adjuster: They usually always pay for homeowner's dumb mistakes and installations. Not so, when a professional does the dumb install.
stoker-man
 
Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
Coal Size/Type: Anthracite/Chestnut
Other Heating: Hearthstone wood stove

Re: ASME Boilers

PostBy: vtec350 On: Tue May 13, 2008 5:12 pm

Yanche wrote:
coaledsweat wrote:
vtec350 wrote:This guys usually known for being a hard ass to deal with and doing everything by the book. Two hours later he called me and said he spoke with Jim and said that the presure relief valve is AMSE listed and he would approve it.


Lucky for you he is also an idiot. :roll:
In my opinion if the building inspector agreed to sign off on the non-ASME boiler installation because it has and ASME approved safety valve he is incompetent. If however he made the judgment after discussing the boiler vessel construction with manufacturer and was told it meets ASME design requirements he's a nice guy. Since none of us were a party to the telephone conversation we will never know.


The building inspector called Jim at Keystoker and discussed the issues with him and they also faxed him all the specs on the boiler construction. I wouldn't think the inspector would put his job on the line and a huge liability risk just to approve a boiler if he didn't feel it was built to standards. My insurance agent, who also owns the company, said as long as it's been inspected and he has a copy of the inspection everythings good. I wouldn't have felt good about it if the ok came from just any agent in the company. I think if this was such a big issue here in Ma. than it shouldn't even be legal to sell these boilers here unless they are going to be installed in an out building.
vtec350
 
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KA-6

Re: ASME Boilers

PostBy: Flyer5 On: Tue May 13, 2008 9:31 pm

CapeCoaler wrote:Ask anyone who worked/works with steam if they want to be near anything that blows.
The problem begins when the relief valve fails to open.
The pressure will then rise till the next “relief valve” opens, usually with very destructive force.
Myth Busters did a show where they removed the relief valve and cooked the water heater till it blew, at 300 psi, turned it into a missile that took a very long time to return to earth.
It makes sense to allow the boiler to be installed with the stamped relief valve because water heaters use 40 -80 psi working pressure and, I believe, do not require the stamp on the vessel.
The part that everyone is relying on to work is the pressure relief valve. If it does its job the boiler is usually under 20 psi



I always install 2 PRVs . Less chance of them both failing .
Flyer5
 
Stoker Coal Boiler: Leisure Line WL110
Hot Air Coal Stoker Stove: Leisure Line Pioneer

Re: ASME Boilers

PostBy: stoker-man On: Tue May 13, 2008 9:37 pm

I know some of the techs don't touch test the PRVs because they're afraid that they won't seal up again.
stoker-man
 
Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
Coal Size/Type: Anthracite/Chestnut
Other Heating: Hearthstone wood stove

Re: ASME Boilers

PostBy: coaledsweat On: Tue May 13, 2008 9:59 pm

Once tripped, a lot of them will drip. Some eventually stop, some do not. It gets worse with steam.
coaledsweat
 
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Re: ASME Boilers

PostBy: Freddy On: Wed May 14, 2008 6:06 am

My entire childhood I thought they were supposed to drip! My Dad kept a bucket under it and weekly chores called for emptying it. He was so cheap! LOL In later years I realized that it dripped more when the expansion tank needed emptying. That was back before bladder tanks.
Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

Re: ASME Boilers

PostBy: Yanche On: Wed May 14, 2008 4:02 pm

coaledsweat wrote:Once tripped, a lot of them will drip. Some eventually stop, some do not. It gets worse with steam.
My approach to the dripping after testing is to make it easy to replace. I install them with a full port ball valve. Then when one continues to drip after testing it's easily removed. I just reuse the cleaned or refurbished one from last year's removal that continued to drip. Almost always, only the gasket or seat needs cleaning. To assure the ball valve doesn't get closed I remove the handle or wire and tag it in the open position.
Yanche
 
Stoker Coal Boiler: Alternate Heating Systems S-130
Coal Size/Type: Anthracite Pea

Visit Lehigh Anthracite