ASME Rating for Hot Water Storage Tanks

[akronme]

At what operating pressure does a domestic hot water storage tank need to be ASME "stamped". I know that when a storage tank goes above 120 gallons then it required the ASME rating. The domestic hot water system in my case will be operate at 60 psi, at this pressure does the tank need to be ASME rated?

 

[vpl]

60 psig or psia? Either way, yes. You may want to look at your local building codes. Fortunately, there is a free site where you can look:

http://publicecodes.citation.com/st/oh/st/OH-P-2005-000004.htm

Patricia Lougheed

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[DVWE]

akrongrad,

Have a look at Section VIII, Div. 1 Part U-1 Scope. Specifically U-1(c)(2)(f) and (g).

 

[stanrick]

Excuse my ignorance. My understanding is that any vessel "needs" an ASME Stamp only when the customer requires it. In turn, the customer requires it because his insurance company or local regulations or his good sense tells him he should have it.

Strictly speaking, a manufacturer who only cares about a sale can turn out any piece of junk and sell it, as long as he doesn't misrepresent it as safer than it really is. A customer who is not constrained by regulations, good sense, or ethics (in an undeveloped country perhaps?) is free install the junk vessel.

Please enlighten me if I am cynically over-simplifying here. I'm kind of playing the devil's advocate.

 

[ANII1085]

The following are exempt from stamping

Hot water heating boiler operated at a pressure not in excess of 30 psig and having a rating not in excess of 200,000 B.T.U per hour.

Hot water supply boiler boiler that are directly fired with oil, gas or electricity when none of the following limitations are exceeded.
A. Heat input of 200,000 BTU per hour.
B. Water temperature of 200 degrees F.
C. Nomimal water containing capacity of 120 US gallons.

leem

 

[moltenmetal]

These rules vary from jurisdiction to jurisdiction.

The Ontario Technical Standards and Safety Act (TSSA) boilers and pressure vessels regulation has a water heater exemption, as does CSA B51 which these provincial standards usually reference. "Vessels" containing "liquids not more hazardous than water", less than 65 C and less than 250 psig, are exempt.

 

[JohnGP]

And stanrick, on the global stage, a vessel that must be compliant with the European PED can use ASME VIII to demonstrate that the essential safety requirements have been met, without the need for the "U" stamp.

 

[Bobfromoh]

I think you should be looking at Section IV, not Section VIII for domestic water heaters.

 

[GenB]

the 30 psi may be wrong, is more than that.
Since hot water can kill, most Jurisdictions accept/enforce ASME rules for stamping 120Gl and over at temp.
Smaller <120Gl shall meet ANSI Stds.
I'm not afraid of Steam, I am afraid of the steam the hot water produces.
GB