How do I bleed my radiators?


Hi, I just bought a Cape Cod and the second floor is freezing at night. It seems the radiators don't get as hot as they do downstairs. It's hot water heat, could this be an issue of the radiators needing to be bled? I can't figure out how to do it. I turned the knobs pictured below and nothing happened. Do these type of radiators get bled from the basement?
http://img85.imageshack.us/img85/9620/dscf0640fy6.jpg
http://img152.imageshack.us/img152/6781/dscf0641qk1.jpg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
That silver canister is your bleed valve. Air rises. Remove the small valve cap and using a small screwdriver, press the pin down under the cap until you get water. Joe wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Looks like you have an automatic air vent (The fat cylinder on top) isolated by a manual shut off valve.
Open the manual shut off (turn the handle so it is inline with the pipe). Unscrew the cap that looks like a tire valve cap. Press on the little pin inside untill all the air flows out and you get some water flowing out.
If you don't get any water, then you don't have enough water or static pressure in the system, or you have a solid air lock; probably time to call a pro.
If you get water, then screw the little cap on but leave it a turn or two loose and leave the manual valve on. The automatic vent has a float inside that should automatically bleed air but not leak water. If water continues to leak out, the automatic vent has failed. You can have it replaced, or you can turn off the manual valve and remember to bleed them periodically by hand.
You may need to repeat this a few times over a few days to get all the air out.
HTH,
Paul
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Paul Franklin wrote:

I believe it is already inline with the pipe from the picture correct? So once the heat starts working properly I should turn to shut off to the perpendicular position?
Unscrew the cap that looks like a tire valve cap. Press on

I just unscrewed the cap and a little air and some water flowed out for about 2 seconds then stopped. There was no pin to press down just an open end. Do I need to do this when the furnace is actually running? - seems like it could be a little dangerous but I could use gloves to keep from getting scalded.
Also do I need to do this to all the radiators in the house? The downstairs ones seem to be working fine so I'd rather not mess with them if I don't have to.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yes, it's on in the picture. I'd leave it on unless you get water leaking from the auto-vent.

The boiler doesn't need to be running; the static pressure should be high enough to get water to all radiators without the circulator running. But sometimes if it is really airlocked it helps to try it when the circulator is running. It doesn't sound like you had much air in there if it only came out for 2 seconds. You can try repeating a few times over a day or two and see if you get hot water flowing.

Usually the air collects at the highest point, but it's not a bad idea to bleed all the radiators once in a while. If they are working well you can skip them if you like. But be sure to bleed all the radiators on the upper level.
Good Luck,
Paul
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

iT'S amazing how complicated this "automatic" stuff is. In college I lived in what had been a 3 story private house, that now had 10 bedrooms and 3 baths, with radiators in every room (plus the living room, dining room, kitchen and a couple in the basement.
We had no automatic, and all we had to do was bleed the radiators once in the fall. And only the ones that weren't hot all the way to the top.
I suppose if there are air leaks in the pipes, it wouldn't last a year, but the house was already proably 60 years old, built in 1905 or so, and the apartment building I lived in next was built in the 30's (it was 1968 then) and they didn't have any leaks.
Hot water is good, btw. Quieter than steam and slower temp changes than hot air.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Call in the professionals for this job. It's a real bloody mess and you could do severe damage to your carpeting, walls and more. You dont want blood all over the house, do you?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
posted for all of us...

He'll use leaches - like the maroons that ask questions without doing basic research.
--
Tekkie Don\'t bother to thank me, I do this as a public service.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.