Air in radiators and low PSI....

Nick_27

I've screwed the reducing valve down (which should increase the pressure) with not much result. I'll try opening the air vent and see what happens. There is only one radiator in the basement in a room near the boiler and then 7 radiators on the first floor. None on the second floor. I've closed off the one in the basement for the time being. The B&G valve looks like it used to have a fast fill lever....

I don't know if the expansion tank is too small. I had the system checked in the fall by a professional and he didn't say anything about it....

Also, isn't the circulator on the wrong pipe? (The return instead of the hot boiler output)

Thanks,

Nick.

Nick_27

Air in radiators and low PSI

Hi there all:

I have been trying to bleed the air out of my old cast iron radiators, but there always seems to be more in there when I check. Also, the PSI in my system seems low, at least when it's cold, and it never gets much above 10 PSI.

It's a converted gravity system, but it's a little odd in that the circulating pump is on the return and not the output (see pictures).

I tried upping the pressure in the system by adjusting the pressure regulating valve. It also seems to lack the quick refill lever (or it was broken off).

Any suggestions?

Thanks!

Nick.

Unknown

is that a A O Smith

Is that a A O Smith coil bolier? Are you getting any water from the radaitors? If not, then the pressure gage is broken as well your boiler feed valve... I never seen pressure reducing valve with fast fill lever on the dual unit. You may have to replace both presure/relief valve as well the pressure gage, while you are at it, check the pressure on the exp tank as well and looks like it may be too small for the present cast iron raditors system.

Unknown

wait a minute....

I rechecked the first picture on my tidy screen of my pager.... U have another relief valve and another pressure reducing valve built in at the exp tank? Something wrong and if I were you, get a real BOILER pro to correct this for your safety.

william_5

air air air

looking at the age of the system i could see a thing or two.is this unit in a basement? and how many floors are there? first the b&g dule vale not all of them came with a fist fill are you screwing the stem up or down ? (up decreass pres. down increass pres.) but most likey the screen is pluger on the vale you have two relif vales so you can go with a single feed if you hade to making shore the other one works the circ is fine i would not re pipe just to re pipe it but is there a tee on top of the circ if so where does it go to?i would re place the air vent( they work,do work or leak the thumb nut on top should be open one turn or two if not no air can escape from the system. ) do you have any pipes in the concreat? if so i would look for leaks the feed vale trys to maintane a set pres.adding make up water and a lot of air with the air vent not working the air ends up in the rad. one last note you do not have an exp tank an exp tank is a tank that hengs up in the rafters or in the atic where air should be vented to also taking up the expanding water. it is a tank you would dran yearly. you have a amtrol #15 extrol tank it in fact may be two small for the system that would be address if you hade relife vales reliving all the time that tank comes pree charged to 12 psi it can be adj in the field to mach the boiler press that tank is a closed tank there is no water to remove when the tank goes the relife vales will dump the extra press hope this helps william

Unknown

I can`t even

see a flow-switch on that, they are a requirement on this boiler type are they not? Take rjbphd`s advice and get it looked at!

Dave

william_5

nick you have a maid of mist auto bleeder at the boiler its the clostest one to the wall not the one with the 3/4 pipe coming off thats a watts374 relif vale does that auto bleeder work? that cap should be loose it has vale like a tire niddle do you get any water out of it?

william

Nick_27

No More air ... but I think one valve isn't working

Well, I think I figured it out.

This thing is a real hogg-podge (see pictures). The black valve comes off the cold water supply and branchs into both the hot water heater and the orange valve. That orange valve leads to another orange valve, then to the B&G reducing valve and boiler. The red valve comes off the cold water supply directly into the radiator pipes.

First, I loosened the cap on the bleeder. Then I made sure the orange valves were open (counterclockwise right?). Nothing changed. I screwed the B&G reducing valve screw down (to increase pressure) - nothing happened. Then I turned the red valve and water flowed into the system and the pressure came up to 10-12 PSI (cold).

Then I turned the boiler on, but as it got hotter, the pressure went up and soon was at 30 PSI and the pressure relief valve started emptying. I opened the valve at the bottom of the boiler and bled some water out till it was down to 15 PSI.

It's working fine now, but the cold pressure is still low (around 5 PSI I guess). What PSI should the system run at when it's hot/cold?

Thanks,

Nick.