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Vent & Radiator Question

First of all, thanks for the valuable information on this site. I have gone from 6+ cycles per hour to 1 (thermostat), no main venting to pretty even main fills and too cold rooms to pretty evenly warm rooms. :) Hammer is basically gone and my next move is getting somebody to install a skim port for me.

2 main runs, 25' & 60'. 25' has one Gorton #1 and the long run now has a functional two Gorton #2s (on a tee).

My son's room (2nd floor) has what I think is a Maid 'O Mist #72 and I have no clue on the radiator maker. This room is off of the short run, which is also feeding 3 1st floor rads, including the thermostat room (living room), and is too warm. I have played with the screwdriver in the #72 trying to slow it down but I don't think it really does anything.

I have Ventrite #1 adjustables on all other radiators (6) except for 4 smaller radiators with Vari-valves (I know, I know, at least now I know).

As you can see in the photos (I hope) the location of the vent is very tight and the radiator is surrounded by a metal case. Are there any other options, vent-wise, for cooling down this radiator?


  • Hap_HazzardHap_Hazzard Posts: 1,349Member
    edited January 2013
    Wrong Vent

    The M-o-M 72 is an autovent for hot water systems. Totally the wrong vent for a steam radiator, and it's in the wrong place. If you pull the thing away from the wall (I know--easier said than done, the way it's installed.) I believe you'll find a boss sticking out of the left side about 5 or 6 inches above the base. There should be a 1/8" tapping in the top of the boss that should accept a vertical vent like a M-o-M 41-M or a USAV or Durst 881. The vertical Varivalve will work too if water isn't a problem, and if you can throttle it down.

    The trouble with these National Aero convectors is they have so much surface area that they just blast heat, and the enclosure gives them very efficient airflow. If you could block that opening at the bottom of the enclosure you might find it keeps the room considerably cooler.

    If you give me the dimensions of the enclosure I can tell you what the EDR is.
    1983(?) Peerless G-561-W-S
    3" drop header, CG400-1090, VXT-24
  • Dave_154Dave_154 Posts: 25Member

    40" x 14" (W x H). It also tapers from bottom to top but I guess you can see that in the first pic. There's really no gap on the sides for a vent, so I'm thinking an external (to the casing) vent might work. There a good 1.5" of exposed casing on the side, so some 1/8" piping and one hole should work. Maybe.... :)

    Since going to 1 CPH has created a leak from the attic radiator I'm going to have to have someone come out.  Also 1 CPH has made the 2nd floor much warmer (4-5 degrees) than the main floor. I guess some 'balancing of the radiators' is in order.

    Fair warning JSTAR. :)
  • JStarJStar Posts: 2,668Member
    edited January 2013

    Oh no...this radiator!! We may have to get creative on that one.
  • Dave_154Dave_154 Posts: 25Member
    If it

    was easy I wouldn't have to ask for help, right? :)
This discussion has been closed.


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