Air Temperature from Slope Top Radiation

bill nye_3

It really depends on the water temperature, the room temperature, the cabinet size of the convector, the room size etc.

But I'm sure some one here will find a chart. Why do you need to know? Just curious.

Dave Elovitz

Where can I find what the temperature of the air should be coming out of commercial slope top perimeter radiation?

Brad White_191

Dave

I wonder if you saw my response to your first posting- Probably not what you are looking for, just my own experience recollected.

http://forums.invision.net/Thread.cfm?CFApp=2&&Message_ID=404745&_#Message404745

Dave Elovitz

Slope top radiation

The hot water leaving the boiler is 200F, the room is 70F. The concern that was raised is about a patient possibly getting burned off the baseboard with the bed right against the outside wall if a hand or foot dangles off the side of the bed.

Dave Elovitz

Slope top radiation

No, I missed your response. If you would answer again, I would appreciate it.

Thank you

Brad White_191

Try

pasting the link into your browser and it will take you there.

If that does not work, I will e-mail you the text off-line.

EDIT: Here it is: In reading your focus, that of patient scalding, coincidentally I did address that as a specific for NY State. To add to that though, I can see if there is an outlet damper which is closed, the surface would get much warmer than otherwise.

So, here is the text:

Date: July 06, 2008 09:34 PM
Author: Brad White
Subject: Surface temperatures

Hi Dave!

I do not have specific data but as part of commissioning several buildings with fin tube, I got readings of about 105-110 by my memory at the tops with about 180F entering the tubes. To be fair, at the time, the water temperature was not specifically noted but was "up there" being in the dead of winter during a heat soak.

My measurement were with a Raytek IR gun, more as a binary function of "yes, radiation is on" than for recording specific temperatures. This was on two-tier 18-inch high cover by the way.

A recent school with fin-tube (system playing catch-up and running 170F to the spaces at the time) under old brass fret grilles behind bleachers, I measured 94-95 degrees at the top. Of course there was a lot of bypass air dilution.

On a more recent building with condensing boilers (using 140F design in the top tube and descending in series to the bottom tube in counterflow) I read about 90-95 F.. Again, no concurrent water temperature noted and measurements for binary check purposes.

You can imagine a taller enclosure drawing more air in dilution even if not bypass, not knowing the temperature of that air- (always 65? HA!), all of those variables, I can see how it would take a lab setup to determine what you seek.

A more specific application was for some hospital work I was doing in NY state some years ago. The NY Dept. of Health stipulated a maximum 125F surface temperature to avoid scalding.

Specifically they allowed fin tube but forbade standing cast iron or in our case, Runtal panels unless we had a "fail to cold" mix-down system of compensated water. So, in NY state at least, fin-tube gets the "under 125F nod" FWIW.

Not definitive data (someone else may chime in) but my experience anyway.

Brad