We have a relatively new gas boiler - 5 years old I think. This last
year I've been hearing a lot of gurgling in the pipes and I figured it
was time to bleed the system.
Well, I seem to have done more harm then good. I bled the upstairs
radiators and at first I heard some air come out - or maybe it went in
through the bleeder valve. I'm not sure. But now there is no heat at
all on the second floor which has 3 radiators. Downstairs seems to be
Upstairs I did not get any water coming out of the bleeder valves.
Downstairs I did get water coming out when I bled the radiators.
I am thinking the system must need a lot more water in it which I know
is supposed to fill automaticaly but maybe that part is not working.
Prior to my trying to do this we were getting some heat on the second
floor. Kind of strange. I think I must have let more air into the
system probably because it is already full of air and not functioning
I guess it's time to call a professionsal.
Any ideas what is going on here?
Thanks in advance,
The water level is likely low, is the pump running, what is the water
pressure when cold. Wait for it to cool and open up the feed, I have an
auto feed but dont trust it and keep the line valves to it closed, many
people keep them closed or lift up on the little bar across the top of
the feed valve to see if you can get it to feed water. With only air
comming out upstairs you are low on water, start by adding only 2lb note
pressure cold and hot. For 3 floors I run 12-14lb.
On Nov 22, 9:35 pm, firstname.lastname@example.org (m Ransley) wrote:
Where is the feed? I see a few turn valves and a few levers but I'm
not sure which one turns puts water into the system.
The pressure is almost 0!!
Water temp says 140 at the moment.
Thanks for the tip about cooling the system first. I was wondering
about that. Cold water in a hot boiler seems like it could spell
Should I call the expert here or is this really a do it your self
project for a moderately handi person? Actually moderately may be
overestimating my abilities.
Is the boiler also used for domestic hot water? If so, there are two feed
valves, one for domestic water, the other for the heating water. Follow
the cold water line to the boiler. It is probably running across the
ceiling and then drops down to the boiler. At some point, it will split
off. One valve will be on the line feeding the domestic water. It will be
full open. The other line will go through a setup (often made by Watts)
that has first, a fill valve that has a lever on the top, then a pressure
relief valve that have a pull handle on the top and may have a pipe on the
bottom to direct any blowoff. The feed valve is in that line ahead of this
assembly. In my case, the fill and pressure valve are on the back, but the
fill valve is on the front. Find it, and see if it is open. If it is
closed, when you do open it you will probably hear water running.
Once you are sure it is open, then you can go back and bleed the air. . It
may take a couple of tries to get all the air out. Do the bleeding cold,
but then turn the heat on and while the circulator is running, if you hear
air, bleed it again. If needed, again and again. Air sometimes get into
pockets. I have a baseboard system and it took four times to get the first
floor bled properly and the water to circulate properly. If there is not
enough water, the pump can cavitate and not push the water through.
You probably also have a drain valve on the return pipe of the heating
system. You may want to drain some water there while the pump is running.
That is where I finally got all the air out. Just open it a crack and it may
sputter as the water passes and air comes out.
Keep in mind, as long as you have some water in the system, you won't do any
damage so try it a few times before spending $100+ for a service call.
You have a hot water output pipe and cold return on the boiler. does
the pump run? The fill valve-valves should be on the boiler return
going to city supply. I would not just turn it on and leave it since you
could overfill it fast if your system is small, at 35lb your pressure
relief would open, you don`t realy want to get above 8-10 cold to start.
I run 12-15 on a boiler in a basement of a 3 story, less hight you need
less pressure. You only want enough water in it to get all the air out
and heat radiatore evenly when hot. I have never blead a system
cold,[but try it], and not running since pressure builds as the boiler
On Nov 23, 8:25 am, email@example.com (m Ransley) wrote:
The way mine is set up the cold water feed is turned on but there are 2
red valves on the way to the main line. One says "reducing" and the
other says "relief". So the cold water feed is already turned on but
it doesn't seem to be working properly.
Is there any thing else I can try to get some more water back into the
system? The pressure is reading zero so it must be very low.
I tried bleeding upstairs again and I heard a little air, but no water
came out and not much air really. Seems like if I wait 1/2 hour I get
a little pressure build up but nothing much, and no water yet upstairs.
Thanks for the feedback,
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