Boiler is working and heating up water but no heat

notoworking

My boiler is working and heating up water but does not send water up the hose. It starts to shudder and shake which I think there might be air in the system but when I try to bleed the air out it does not autofill the water. My autofill does not have a system bypass so I don't know what to do.

HVACNUT

Is there pressure on the boiler?
Is it possible the loop is frozen somewhere?
If it is air locked, you can try to increase the pressure to about 20 psi while purging. That should be enough to push through. If its frozen, not so much. 

pecmsg

notoworking said:

My boiler is working and heating up water but does not send water up the hose. It starts to shudder and shake which I think there might be air in the system but when I try to bleed the air out it does not autofill the water. My autofill does not have a system bypass so I don't know what to do.

That's very concerning. Without more information I'd error on the side of Caution and Shut It Down until you can get someone out there!

Jamie Hall

Indeed. Shudder and shake is not confidence building. Shut it off. Start with the simplest step: is there enough water in it? For that matter, is there any water in it? Let it cool down completely -- whatever else you do, don't try to add water to the system when the boiler is even warm. There must be a drain valve somewhere on the system -- open that and see if you get any water at all. Open a bleeder somewhere upstairs; you should get a nice steady stream of water.

You mention an autofill valve -- with no bypass? Does it have a manual fill lever? Most of them do. If you get no water in either of the above tests, see if you can persuade it to work. If not... unless you are handy with plumbing and heating system piping, you are in over your head and need to get a competent professional out there to fix that problem. If you can get it to work, run it (you'll need a helper) until you get a good steady stream of water out of that bleeder -- pick one at the highest elevation you can.

If you aren't positive at this point that the boiler is full of water and there is water in the rest of the system, even if there is still some air, stop. It's time for a professional.

If you are positive, leave the boiler off and start the circulation pump or pumps. It may be hard to discern, but you must get some flow out of them. If you can't tell, or if you think there might be no flow, again -- stop. It's professional time.

I have to admit... on the whole I think it's time you called in a good heating professional to take a look at the situation and fix what needs fixing...

notoworking

I think there might be a blockage somewhere in the system because the boiler heats up the water and tries to send it up but then after shuddering it shuts down.

notoworking

How should I try to remove the blockage in the pipes?

notoworking

Also everything in the system works. It heats up the the water to the right temperature the pressure is at around 20 psi. The pilot is working its just that the water refuses to to go to the top.

notoworking

The circulator tries to push the water upwards and doesn't succeed, hence the shuddering and shaking. I should also mention that when I try to bleed air out of the system only a little water comes out then nothing. The pressure stays at a constant 20psi

JUGHNE

Where are you located? Have you had severe freezing weather beyond the normal for your area?
Does all of your faucets flow water inside the house?

How many floors in your house?

If you go to the highest air bleeder (on a heater that you know usually works) and only get a little water and IF the pressure still is 20 PSI......you probably have frozen pipes on the heating system.

Getting a little water may mean that the frozen part is starting to thaw out and may open soon.
While you wait for the thaw, I suggest shutting the the power switch to the boiler off and also shut of the manual water supply valve for the boiler.

If frozen and then thaws there may be a split pipe. If the water fill valve is left on then it would continue to push water into the system and out of the split pipe.....if you have one.

notoworking

Sorry I was reading the gauge wrong. The psi is around 9 and I live in a 2 story building. This is a separate heater for the top floor. We have 2 different heaters for two different floors. The normal operating psi should be about 12-15 psi but the boiler is at 9 psi.

JUGHNE

Which one is the problem unit?

Show pictures of it?

Where are you located?

notoworking

The one that goes all the way up to the second floor. It is low on pressure at 9 psi and also has now started to turn on and off after I bled air out of the system. It says low water and the light blinks on and off with the boiler.

JUGHNE

I think this is beyond your DIY expertise.

You need to call in a professional.

EBEBRATT-Ed

@notoworking

If you want help we need pictures. The posters above have asked questions that your not answering. You best bet is to call your heating tech as @JUGHNE mentioned. 9 psi may not be enough to heat the second floor.

Is this hot water or steam? do you know?