Limit Control for steam valve on S&T??

I know that you need a hard-wired limit control for gas-fired heating applications, and I've also used hard-wired limit controls for electrical heating applications.

BUT

What about a solenoid valve that opens up the flow of steam through a Shell and Tube heat exchanger? Seems like a reasonable thing to put in, because its so close to the other heating applications.

Has anyone ever been directed by an Authority Having Juristiction, to install such a thing?

Has anyone ever been directed by an Authority Having Juristiction, to install such a thing?

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No, never have, but Think Safety anyway.

Of course, if it were my money, I'd have one on there in a minute.
But I need some compelling reason to share with the end user...Chapter&Verse.

I'm working under the impression that a high limit control is for fire protection (NFPA 85/86), due to the ability of the energy source to raise the temperature to levels that can ignite either the vessel (oven, furnace, heater, kiln, whatever) or the surrounding area.

A methane gas flame temperature is 900-1500°C

However, steam vessels must be pressure rated to contain the pressure. So the shell can get as hot as the steam is. The temperatures that saturated steam can achieve are substantially less than vessel or surrounding ignition temperatures (paper's autoignition temperature is 842°F)

100# steam is 337°F. That'll burn your skin, but it won't ignite paper.

160# steam is about 370°F, still not enough to ignite paper.

I don't see the fire hazard.

The safety control on a steam system is the pressure relief valve, but it's not for fire prevention.

Possibly the most common example of steam solenoid is on laundry and commercial kitchen equipment. Kitchen dishwashers used to use 205 F water for rinsing and final sanitation. Steam was used to heat the water via shell n tube heat exchanger.

Other examples are space heating tank heaters etc.

Compelling reasons
1. Common sense (OOOOPS)
2. Like a thermostat on any electrical equipment - you need to turn off to prevent overheating - ESPECIALLY so if heating domestic water with steam.
3. If you do not turn off steam and you do not have steam trap then the condensate return pump will have difficulty pumping steam. Same situation with failed trap.
4. If he does not want to do the right thing tell him to have someone else do the install
5. He is severe cheapskate with a very bad rectal cranial inversion.
Dan Bentler

leitmotif said:

Possibly the most common example of steam solenoid is on laundry and commercial kitchen equipment. Kitchen dishwashers used to use 205 F water for rinsing and final sanitation. Steam was used to heat the water via shell n tube heat exchanger.

Other examples are space heating tank heaters etc.

Compelling reasons
1. Common sense (OOOOPS)
2. Like a thermostat on any electrical equipment - you need to turn off to prevent overheating - ESPECIALLY so if heating domestic water with steam.
3. If you do not turn off steam and you do not have steam trap then the condensate return pump will have difficulty pumping steam. Same situation with failed trap.
4. If he does not want to do the right thing tell him to have someone else do the install
5. He is severe cheapskate with a very bad rectal cranial inversion.
Dan Bentler

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@Dan:
Since my customers, workmates, and students read my comments on here, I need to say that I did not mean to indicate a non-willingness to spend money on his part..only that if it were MY money, I would do it.
Yes, some "people" are really tight with money, and they have their reasons for it. But it has not been stated (yet) in this case.
And, thank you for your insight...we apparently think alike in this regard.

One thing to watch out for with steam is to ensure as much as possible no residual water left in item to be heated. This is cause of "clanking radiators" in buildings. Water left can flash to steam then condense. Has been known to break pipes.

You may (probably ??) need a steam trap for the condensate off your heat exchanger.

Like any other energy source steam is great stuff if properly installed maintained and operated. Improper leads to all kinds of exitement at minimum and in severe cases major damage and possible severe injuries.

Dan Bentler