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# Steam Pressure Guage for new installation

Member Posts: 5
A great steam guy (and I) just installed a Peerless ECT 3 section steam boiler. I have a bunch of comments I will share that may be helpful to you all, but I have a simple question: the pressure gauge on the boiler ranges from -30 to +30 PSI. We are trying to operate at 1/2 lb PSI which barely moves the needle. Is there a gauge that ranges from 0 to 5 PSI? What about a combination temp and pressure?

• Member Posts: 1,320
It is essential...

That we install 2 pressure gages!

One to meet code, which states: "A pressure gage rated at twice the maximum boiler pressure rating shall be installed."

Since virtually all steamers have a 15 pound burst rating, the gage is compliant at 30#

Those of us in the real world of steam, know a 0-5# gage is required to make them sing and dance. This is why we have tees; to hook up a second gage that is relavent to the real world we embrace...
• Member Posts: 5
Steam Pressure Gauge for new installation

So now I know why the gauge goes up to +30#. Is there ever a situation where the system will see negative pressure --- the gauge also goes to -30#?

Do you have a favorite source for the lower PSI gauges?
• Member Posts: 1,320
All steam systems...

Will go into vacuum when the steam collapses from the combination of temperature and pressure drop. Some will not be measurable. But given that steam occupies about 1,000 times as much volume than the droplets of water they are spawned from, some serious contraction takes place!

Many of the older steamers were designed to release the latent heat at temps well below 212, the boiling point at sea level. By inducing a vacuum, we could release the latent heat at temps, down to the mid 100's by simply making the system hold a vacuum. Making combination gages just as relevant as the zero and up/only ones common today.
• Member Posts: 1,405
Vacuum Range

the gauge also goes to -30#

I think you will find that the gage goes to -30 inches of Hg (mercury) which is about -15 PSI from atmospheric pressure. [I know, minor technical bullscat]
• Member Posts: 183

I like the idea of 2 gauges, but my supply house said they did not sell a pressure gauge below 0-30. The 0-30 on my boiler says "Internal Syphon" and is made for steam, but I can't find a "steam" gauge below 0-30. Is there a brand that works? If not, should I use a pressure gauge like a wika one that only goes up to 140 degrees? Do I need an external siphon in that case to keep it cool enough? Or does it not matter?

Thanks,
Tim
• Member Posts: 8
steam/vacuum guage

After trying numerous of the cheap guages (even the ones with the right range in pressure and vacuum)and getting tired of inconsistant readings I found a stainless steel panel guage(us guage) that is meant for critical applications. It cost more but now I can get my 8 oz pressure and also found that the vents on the returns were intermittently working (vents bad) by watching the vacuum after firing cycle. The other guages showed pressure but vacuum was not displayed until it was at max for the system. The old guage(at least 40) worked great until last year. It was a 30lb (with a long scale up to 5 pounds and a vacuum scale to 15 ")
• Member Posts: 324

FWIW. I bought the Wikai 0-5 psi gage last year, at the suggestion of a Wallie. Works great so far. Shows clearly what the boiler is really doing pressure-wise.
• Member Posts: 8
Try State Supply Company

I did just what you want and I now have a 0-10 PSI pressure gauge. Cost \$10. While I was at it I also installed Vaporstats instead of my pressuretrols.
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