On Jun 19, 11:17 am, coustanis wrote:
On Jun 18, 11:58 am, "Edwin Pawlowski" wrote:



"coustanis" wrote in message

Ok, the room that has the radiator pipes in the concrete slab has been
isolated and I put about 22 pounds of compressed air into it. After 4
or 5 days it had lost most of the pressure. In a day or so it will
probably be empty.
I assume then that there is a leak in that room unless there is some
other furnace phenomenon that would cause a system to not hold
compressed air. Since I don't see any water I assume it's in the
concrete pad.

Your connectors or your valve may have a leak also. Check them with a
bubble solution to be sure they are not part of the problem.

BUT...

The furnace it still losing pressure.

You don't have a furnace, you have a boiler. Furnaces heat air, boilers
heat water.

Since all the pipes are either
visible or within the walls if this wood and sheetrock
house, I would assume that if there were an additional leak that I
would see a wet wall, a puddle or water dripping from a ceiling. I
see no water.

You are probably correct.

Someone in a previous thread said it could be a bad expansion tank.
The expansion tank is brand new and was installed after this pressure
problem started. The auto feed valve is closed and has always been
so, even when the system was not losing pressure. I'm not sure what
to do next or what to check. I can isolate another loop but I'm
wondering if it's a leak at all in this part.
Does anyone have any ideas?

At least twice I've suggested you leave the valve open to be sure all the
air is purged. Have you tried that? Seems as though no. Another poster,
hvacmedic, also stated the valve should be open and gave a detailed
reasoning behind it all. Listen to the pro.

I took off work today to mess with this.

I replaced the boiler feed valve. The old one had the adjustment
screw loose and it was easier to spend 40 bucks on a new one that
was factory set. When I took the old one off I saw that it was heavily
damaged by electrolysis. Some of it's internal parts fell out through
the fitting
holes.
After install I left the new one in the auto position with the
isolation valve open as was suggested.

I verified that the expansion tank was good by checking that air, not
water came out of the snifter valve and that it's pressure equaled the
boiler pressure.

I isolated the entire second floor of the house by cutting and
capping. I know this sounds extreme but it only required two cuts and
two caps.
Total time for that was 10 minutes and 3 bucks. This allows me to
have no pipe connected to the boiler except what I can directly see.

Closed the air purge valve at the top of the system.

I filled he system to 20 psi. The feed valve kicks in at 12 psi.
If it maintains 20 then I fixed it. If it drops to and holds 12 then
I assume I still have a leak somewhere
although I can't imaging I have a leak that I can't see, at this
point.

Nothing to do now but wait a week and see what happens.

Look folks, I know I've been a pain in the ass with this. I get that
way when confronted with expensive things I don't understand.
I learned a lot and saved a pile of money. I needed to learn this
system. I couldn't go and spend a hundred bucks an hour every time
the system burped
or did some weird thing.

I do appreciate the patience and the advice.
The offer for beer still stands.

Which doesn't change the fact that I have a leak in the pipe under the
concrete slab but, that's a separate issue I'll deal with that later,
after I get the main system set up properly.