bleeding the air from a HW system

[sstan]

ok .. hooked up my OWB and of course had to tare apart the oil burner. My system is a pressurized system with four zones with seperate pumps. All back and running but not heating as I expected .. transfer from OWB to Oil burner is fine .. just not getting the heat from the baseboards. I wondering if I have air trapped in the loops. There is no bleader valves in the upstairs .. only down at the burner .. each loop has a bleeder there. How can I tell if there is air trapped? will that cause the bad heating? Bleeding suggestions?

 

[Corey]

Hopefully, this will get moved to the Boiler room - there is lots of knowledge there. But it sounds like you may have some trapped air - possibly around the circulation pump if you've got one. Is there any chance you can loosen a fitting at or near the highest point in the loops? If you can do it without flooding anything, that would be the best place to purge air.

 

[Gene C]

If you hear water movement in the pipes or fin tubes when you turn on the circulator pump then you have air in the lines. Normally all that you will hear is the "ticking" of the heating pipe. Bleeding air at the highest point in the system on each zone is the easiest, fastest and most effective. However, if installing bleeders there is not an option then flooding each zone 1 at a time is another option. However, before we start we need to know if you installed an automatic bleeder or any bleeder at the highest point of the OWB. If you have a bleeder or hose fitting at the highest point of the boiler you can use that to bleed the house system. (Especially useful if above the highest heat point in the house) Remember, 1 zone at a time until all air is out of that zone. Then close that zone and move on to the next.
I usually input water at the oil boiler and force it thru the zone and out to the bleeder or hose at the top of the OWB. This also keeps the mess outside.

 

[sstan]

Hmm .. not a real plumber so I am not sure I know what your talking here .. but maybe. I am affraid to admit it here but I put in the oil burner 11 years ago when I built the house .. it's not pretty but does work. No way to bleed at the hishest point (bad design on my part). So in the basment at the boiler .. each zone had a pump .. vales on both sides of that. Above the ball valve is a .. well not sure what it is called ... but it has a fitting for a garden hose and a pepcock to open and drain that one zone .. above that at the elbow before the celler cealing is a little .. well tire valve thing. Wow .. now you really know I am not a plumber! I have purged air from the tire valve thing in the past. I will try and post some bad picts of it.

 

[Gene C]

I see you are using a heat exchanger hooked to the OWB to heat the oil boiler. I didn't know that before, so you can forget about most of the process I suggested earlier. I guess you can try to bleed as you have in the past using the bleeders located above the boiler.(" tire valve thing")
You may also need to hook a hose to the valve above the circulator pump and bleed from there a large quanity of water to force the air thru the system. Make sure you close the ball valve above that same pump to insure that you are pumping water into the oil boiler and thru the baseboard and out thru the hose. Put the end of the hose in a 5 gallon bucket and watch for bubbles. When water flow is constant with NO bubbles, close that zone and move to the next.

Good Luck!

 

[sandman59]

If the bleeders on the elbows above the pumps are manual valves, replace them with automatic bleeders. They will continously bleed any air that gets in the system. When I was in the plumbing business in my younger days, on problems jobs, we would do one zone at a time and sometimes have to increase the water pressure to force the air out. Note - always keep the pressure below the relief valve setpoint and remember to reduce it back when done)

Question - After seeing the plate heat exchanger in his picture, is that the way to go when tapping into another system? I also have an oil-fired boiler and I connected in parallel as shown in the EKO manual.

 

[Dave T]

In my limited experience with hydronics Bondo is right splice your lines while air is already trapped in the house piping because you do not want to go through this again,on my system I have to loosen little bleeder caps that are at every radiator yes some time and paitience involved go with automatic bleeders if possible.. The reason that the plate exchanger is being used in his system is because he is running an open system OWB to a pressurized oil boiler,in your case Rich you are pressurized with both boilers no need for an exchanger..Dave

 

[sstan]

Thanks for all the advice guys! I have thought about the bleeders upstairs but to be honest the cutting soldering and such upstairs is not appealling. In the 13 year .. till I messed with it to hook up the OWB I never had a problem. I did hook the hose up to the port above the pumps last night .. opened up the automatic fill valve till I got a steady stream. After I got it all done It sounded like I got the air out .. no more rattling noise .. guess I have to wait and see at this point. I am going to consider replacing the manual bleeders with automatic ones in the celler!

off subject .. anyone know where I can get an inexpensive Temp gauge to intall the the OWB loop..?

 

[trehugr]

Temp gauge http://www.pexsupply.com/product_dtl.asp?pID=7228&brand=Boshart&cID=864

 

[digger104]

How about using a tap on fitting like they use on a line for a ice maker, for the water, you just put on the clamp and screw down on the screw and now you have a place to bleed the air. These work on copper or plastic.