2nd floor radiator not filling with water

[MasterPlumbersKeymaster]

The second floor radiators are not filling with water to the vent valve. The one radiator that is only a foot off the floor will vent air then water. Then loses water over night. The hot water boiler in the basement is carring 8 psi.

[SylvanLMPParticipant]

quote:

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Originally posted by john1330:
The second floor radiators are not filling with water to the vent valve. The one radiator that is only a foot off the floor will vent air then water. Then loses water over night. The hot water boiler in the basement is carring 8 psi.

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WOW John today is YOUR lucky day you found ME.

Having 8 PSI will elevate your water to a height of 18.5 feet above your boiler NOT Good Enough I am so sorry to say

You see the manufacturers factory set the automatic feeder for 12-15 PSI.

Now instead of just boring you with an answer let me explain WHY the pressure is so important so you can also be an expert.

If your boiler was installed by a professional you will have a gauge that shows the following.

1- Temperature of the boiler water

2- A red area showing 30 PSI and hopefully a needle never moving.

This never moving needle was set by the installing plumber.

Now lets get to the nitty gritty

The non moving needle was the COLD FILL static pressure.

In another words the Licensed professional let this system fill with cold water and manually bled this system until all air was out.

Then this highly professional Licensed Master Plumber said to himself “HEY this is great BUT how can I make SURE I have a positive system pressure?”

So he/she decided to add an extra 4-5 pounds just for good measure and here is where the needle was set.

Now we also know water when heated in a closed place will expand (we call this phenomena PRESSURE TEMPERATURE RELATIONSHIP)

But we now have already set our pressure and here we go firing up our boiler and WOW the pressure continues to build up HOPEFULLY less then the set pressure of the relief valve (normally 30 PSI)

With this increase of temperature and the pressure we know we have a pressurized system with no air BUT now we have a problem WHERE to put this EXTRA Expansion and here come the expansion tank to the rescue (unless you have a really old atmospheric system open tank).

So what you need to do is increase (Cold feed) the pressure on the automatic feeder by slowly turning the screw down after loosening the lock nut.

Try to keep your operating pressure around 22-25 PSI

For your information you take the pressure and times it by 2.31 and this should give you a close idea how high the water will rise.

Have a great one and if you have any questions please feel free to E mail me.

[kenny bParticipant]

with the boiler cooled to room temp increase the pressure on the fill valve until water comes out of the bleeder of your highest radiator,thats it. Don’t add an-tra 5lbs. thats just plain foolish, its not needed and causes higher working pressures. Congradulations on your good luck of finding him!

[GuestParticipant]

I can assure you that Sylvan does know his basics. He has expressed them here hundreds of times. This time he was using his New Yawk humor to stress some points.

As a lifetime trade teacher, I’ve learned, even in Education 101, that sarcasm is not a good teaching tool. The person has to know what the good information is before he can evaluate what must really be done. For this forum of experienced tradesmem, the post was clever and entertaining; not so for the novice. But that is the hazard and charm of the internet; this is not a public education institution where everyone must toe the line to teach. Masters can express in their own way – entertaining at times.

Sylvan is recommending some very influential educators in the industry.

Harold Kestenholz
formerly, Director of Education
IBR Schools
presently, NOTA Education Chairman

[Author]

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