Rookie mistake -- Air in the lines

The rest of the list may shoot me, but if you have a drain for your pressure relief, pop the valve and let the make up water flow back in. Quick fix to a nasty problem. Try to isolate your circuit is possible.

Having helped many people with boiler startups it would appear that air trapped in the boiler is the #1 problem when first starting up a boiler.

Even with air seperators and air vents it is diffucult to get the air out of the system during the first several burns.

I have used the method of purging the air out with the pressure relief valve in addition to the following:

1.) Turn the circulator pump at the return side of the boiler pump on/off, on/off, on/off many times until the air "pockets" are gone.
2.) Crack open a fitting on the top of the storage tank so that the air can be bleed out of the top of the tank while initially filling with water.
3.) Make sure to fill the boiler from the bottom while cracking the pressure relief valve open.
4.) I always recommend the installation of an analog T & P (temperature and pressure gage) so that the temperature of the water exiting the boiler can be compared to the temperature of the water inside the boiler itself (via. digital readout). Quite often if there is air in the boiler than the temperature of the boiler (internally via. digital readout) will be higher than the analog gage is showing.

Good luck in getting all the air out. After a few burns the air will be all gone and operating the boiler will be a much less frustrating task.

Brian

turfman said:

Well I got my Vigas 40 plumbed and wired and all was well, no leaks, everything tested fine, fired up the boiler, started gassification-- everything was great until..... I have an air lock. I didn't put any air purgers (bleeders or whatever you want to call them) on the lines through my attic (I have a slab house). Now I don't know how to get the air out. Anybody have any good ideas???
My boiler is in a room off of my garage. I have shut off valves and unions on both ends of the return and supply.
Any help would be great.....

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What is your fill pressure? And are you running a multispeed pump by chance?

Increasing the velocity of the pump will help purge any air out of the system. If your fill pressure isnt high enough, that will also make it hard to squeeze the bubbles out of the lines.

If you are sure its air up in the attic, can you shut down the system, cut in a fitting, and put an air vent up there? A manual vent up there would get you back in business.

I'm almost embarassed to admit that it took me 2 years and the addition of one extra vent to finally get all of the air out of my system. It can be a huge pain. I battled a few problem spots for the whole first year before I finally sucked it up and tore some pipe out to add a vent. Vents...properly placed...shall set you free. The trick for me was that the proper location of a vent is not always entirely logical. Pumps can move air into some interesting spots during normal operation.

I agree with all the above. It took me a few burns to get all the air out of my 700' feet of 1 1/2" UG PEX that goes uphill from the boiler to my house. The highest point in the house was the pex fastened to the floor joists the fed my HX in the furnace air handler. I added a vent and a bleed valve here thinking I could get it all out while filling the boiler cold. Never could get it out cold. Finally realized that getting the boiler really hot allowed me to get it out through that vent and the one by the boiler.

turfman said:

Thanks everybody!! I finally bit the bullet (I ran black iron pipe) and drilled and tapped to put in the little air vents and that has most of the air out and it is pumping through!! YAY!!
Always scares me to tap something -- I feel like my threads will not be as good as factory threads, but it worked.

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Glad to hear you are in business turfman. Did you have a wood burning boiler before and move into the new one? Good luck with the new system! And keep us posted. Have you posted pictures yet? I have a thread going for boiler system pictures and wood fired forced air furnaces. I'd like to see your heating system. Have a good one man.

turfman said:

Thanks everybody!! I finally bit the bullet (I ran black iron pipe) and drilled and tapped to put in the little air vents and that has most of the air out and it is pumping through!! YAY!!
Always scares me to tap something -- I feel like my threads will not be as good as factory threads, but it worked.

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I drilled and tapped 2 pipe plugs and put in my air purge vents and it worked fine.

Rob

where is the best place to put your air vents? should you have someon the manifolds for the pex along with supply lines? should i have air vents on my supply from my wood boiler to my fossil boiler?