Boilers - Steam and Hot Water Systems - Upper floor heating problem

My home is like a tri-level plus a basement. The original house was one floor and then the two story addition plus basement was added in the mid 80's. The original part had the heat changed to underfloor about 6yrs ago. There are 5 zones, basement, original floor, master bedroom, living room and 3rd floor where the rest of the bedrooms are located and the hot water for the home. I was sold the heating system and it was inspected by the heating contractor who designed and sold me the equipment and the local plumbing inspector. All the zones work well with the exception of the 3rd floor, it hasn't worked well since it was installed. The first couple years I messed with it, I thought I wasn't getting the air bled out of the system good enough, but I don't believe that anymore. The 3rd floor will work for a few days/weeks after I refill the system and get the pressure up to around 15psi, but then the pressure drops to below 12 and no more heat. This year I decide it must be the pressure regulator fill valve with the backflow preventer must be bad since it won't hold pressure, I replaced it and the system still won't maintain pressure. The new regulator valve has a bypass on it for fast fill, I still don't hear it working, filling to any pressure? I don't know where the water goes by the way, never any indication where it went. After reading stuff on the net, I wonder if the expansion tank is in the proper location in the system. The water line is attached to the backflow preventer to the pressure regulator through a tee that has the expansion tank to a tee for the zone return lines the pump and then the boiler. All of this is mounted low, about the height of the top of the boiler, except the expansion tank, which is right next to the floor. I've seen several diagrams showing the expansion on the line that feeds the zone control valves, and pictures quite often show it in the floor joists. I think the reason the 3rd floor won't heat is because I loose pressure and maybe because the expansion tank is not installed properly, does that make since? I can take pictures if that would help? The expansion tank is also mounted horizontally if that matters?

Pictures always help. There are three types of expansion tanks. One that is open and is usually in the attic. Not so common but they are still out there.

The other two types are a bladder and non-bladder. The non-bladder type is typically what you see hung in the joists above the boiler. This is just a big tank that allows the expanding water a place to go. Has a air pocket in the top of the tank.

The bladder type has a membrane separating the water from the air pocket. They can be place almost anywhere near the boiler. Some are even floor standing.

As for the pressure drop and lack of heat on the 3rd floor, what may be happening is that air in the system is working it's way to the upper levels. This happens over time with the result being no heat in that area.

This will also show up as a drop in pressure. As there is less altitude to the water that remains in the system. It doesn't go as high up and hence applies a lower pressure to the system.

But at the same time it sounds like the auto-fill valve is not adjusted properly or is bad. As it should maintain the pressure as the set point.

With the new backflow/regulator fill valve and even with the fast fill open, with no water entering the system. Is there another valve someplace in that pipe that is closed. Usually house hold water is at 35 - 60 psi, which is well above the boiler requirements.

Al.

Third floor combined with pumping into the boiler can cause these headaches.
When the pump is off, the pressure fills the rads an the third floor, but just.
Then the pump comes on and drops the pressure below 0 psi and it starts to suck air in from any auto vents or minute leaks.

May not be the exact problem but I'd bet it close to whats going on.
Bring the static fill to 18 PSI, and get everything back up and running.

If the pressure builds as the boiler heats, you may need to bring the fill pressure (air) in the expnasion tank to 15 or 18 psi as well.

I have seen an installation where I was called in to see why the system was never getting rid of the air.
Everything looked ok until i noticed a little bit of water near a basement baseboard rad. They where on there own zone pump, and of course it was after the rads. Pump turned on and the leak stopped. Luckily (for me) the rads where plumbed with Wirsbo PEX (translucent) and where I saw a leak before, I could now see air bubbles coming in from the leak.

I'll get some pictures this weekend. The tank is quite small, I would say less than 5gal's. The backflow/regulator fill valve is brand new, I replaced it because I couldn't find anything else. It says it is suppose to be preadjusted for 12psi, suppose it could be wrong? Even when I lift on the manual fill, it doesn't seem to change anything. I was it to push the air out of one of the bleed valves on the 3rd floor baseboards. I also expected the pressure to eventually start to go up as the system filled. There is a valve by or part of the tank setup, it's turned all the way counterclockwise, so I believe it to be open.

I'll try to see if it says whether it's a bladder type or not, the boiler and original system was installed when we built the addition in the 80's.

I've filled the system 3 times since I replaced the backflow preventer a couple weeks ago.

Is there a place to check how much pressure is in the expansion tank? Do I need a special gage? The gage I'm looking at now is on the side of the boiler.

The flooring upstairs is carpet, so I suppose it could be dribbling there, never noticed it wet before I start messing with it though?

I think we should wait to see the pics before too much 'guessing' happens... but I've got one 'guess' to think about:

you said:

There is a valve by or part of the tank setup,

And this makes me wonder if you have a "FILL-X-TROL" setup?

If so, a pressure reducing valve in the line is redundant, and the FILL-X-TROL will set the sytem pressure itself, based on the air pressure charge in the tank.

We'll know when we can see...

Not sure if this is how to add pictures, there may be an easier/better way? A picture of the zone valves, one of the regulator and backflow preventer, one of the expansion tank and one of gauge showing less than 12psi.

new regulator and backflow preventer picture by Shaf_bucket - Photobucket (http://s634.photobucket.com/albums/uu66/Shaf_bucket/?action=view&current=Pictures00325.jpg)
expansion tank? picture by Shaf_bucket - Photobucket (http://s634.photobucket.com/albums/uu66/Shaf_bucket/?action=view&current=Pictures00425.jpg)
below 12psi picture by Shaf_bucket - Photobucket (http://s634.photobucket.com/albums/uu66/Shaf_bucket/?action=view&current=Pictures00525.jpg)
5 zones - one zone is the hot water heater picture by Shaf_bucket - Photobucket (http://s634.photobucket.com/albums/uu66/Shaf_bucket/?action=view&current=Pictures00725.jpg)

1) you are pumping into the expansion tank, therefore you will decrease the pressure at the suction side of the pump. This will decrease the fill pressure up on the third floor.

2) there needs to be more than 12 psi in the system for the third floor I would say. You should be able to get the system pressure up to 20 PSI no problem. There must be an issue with water getting into the boiler (or in this case the fact no water gets into the boiler).

Find out why there is no water getting into the boiler.
Fill pressure regs are directional, I have put one or two in backwards before. Makes for areal head scratching few minutes.

Once you have the pressure problem licked then you can decide on moving the expansion tank and getting it placed pointing up the way it should be.

Mike, what is the distance from the boiler to the top of the third floor rad. The general rule of thumb is 1psi for every 2 ft. of height. The water feeders come factory set at about 12psi but that is just a general setting because it is enough to fill a 2 story system in most cases. On your new valve if you open the fastfill you should hear water come in. If you don't check for another closed valve somewhere. When you changed the valve you must have had to shut something off. You can also adjust your pressure by unscrewing the top lever of the valve, loosen up the nut and turn the screw clockwise until you get the pressure you want. I usually run 20psi in systems and if they are set properly they shouldn't increase by much when running. When I say 20, that is 20 with the pump off. Remember, every time you bleed air out you're going to lose pressure and if it drops below what the valve is set at it will just feed back in bringing air with it. Bring the pressure up to about 28 and bleed the rads if you have to. You don't want any water filling the boiler while your bleeding. If the pressure is high when you finish drain the boiler a little to get what you want. If there are no leaks in the system you should be good to go.

Guys, take a close look at the expansion tank... and the valve it is attached to... looks like a FILL-TROL, don't it?

Take a look at the label on the tank and see if it says FILL-TROL...

Take a look at this brochure:

http://www.amtrol.com/pdf/extrolbrochure.pdf

scroll down to the section on the FILL-TROL and if this is what you have, this is the reason you are getting no water into the system. You need to put some air into the expansion tank! If you have less than 12 PSI in the tank, you will get less PSI in the system... that's the way them things work (or DON'T work).

Mike, in addition to the heli-coil, it looks like the exhaust valve is stuck on that one cylinder... ooooops, wrong pics!

Did you ADD the other regulator? or just change it out? There's no need to have two regulators. I would get rid of the fill-trol valve, and get a standard expansion tank (the one for the FILL-TROL system is different! There is a 'plunger' inside that operates the fill valve).

Wow, lot's of good questions and info. I'll try to answer all as best as I can understand you. Thanks for all your help.

If that is a regulator on the expansion tank, yes, I did add a second one. What I originally took out was a backflow preventer, by itself, the new backflow preventer I bought also had the regulator as a whole unit. Guess I need to remove one of them? The regulator and backflow preventer were together as a unit, and there is also a flow direction arrow cast on the side of one of them, don't recall which one at the moment. You can't see it in these pictures, but the shut off valve is upsteam a couple feet from the backflow preventer, it is on. I did try once to adjust the regulator per the instructions, did a couple full turns and didn't hear any flow, so I turned it back? I did try the fast fill, I couldn't hear any water filling. Maybe the original regulator is not working and that causes the new one not to work? I don't ever recall hearing the fill valve do it's job, even when new, maybe it has never worked? Two of you guys mentioned getting rid of that expansion tank, what should I get and where in the system should I put it? Physically, should it be in the floor joists above the furnace or does that matter? In the system, should it be in the inlet or outlet to the boiler? How do I measure what PSI I have in the tank now?

I agree the helicoil is a problem! :) Now how to fix that?

I didn't answer the heighth question, I am at work, but I'll try to estimate. The expansion tank is mounted near the basement floor. From basement floor to the first, is approx 8 feet, another 8 feet to the ceiling, there is about 2 feet from the 1st ceiling to the 2nd floor and the baseboards are up 8 inches or so. Estimated 18 1/2 feet?

Mike, the reason that you aren't getting any flow through the new valve is because the old valve is preventing water entering the system. Check that link to the brochure I posted and read about the FILL-TROL system... also, take a look at your old expansion tank and tell us what the label says... does it say FILL-TROL, or EXTROL?

In lieu of the brochure, I'll put a small explain here:

The FILL-TROL system uses a special expansion tank that has a 'plunger' in it. When the SYSTEM pressure goes below the TANK AIR PRESSURE, that plunger extends from the tank and presses into the VALVE, which then opens, and admits water to the system.

The net result of this is that the SYSTEM pressure when cold will (should) always match the AIR CHARGE on the tank. If the system pressure is low when cold, it's because the air charge on the tank is low.

If you remember how much you turned the NEW valve, SET IT BACK to the way it was. You might be able to tell by looking at the paint on the adjustment screw.

When your system is cold, look at the pressure gauge. If it is below 12-15 PSI, all you need to do is add air to the tank with a small compressor or bicycle pump (on the end of the tank there is a tire valve, under a plastic cap). When you start adding air, you should see the system pressure start to rise, and possibly hear the water filling the system. Go slowly with adding the air, and let the pressure stabilize before adding more air. You don't wanna blast a ton of air in there before the water has a chance to catch up...

There's nothing wrong with leaving that tank and both fill valves in place if everything is working. As long as the NEW regulator is set a few PSI ABOVE the old valve, everything will work fine.

It could be that the expansion tank has a busted bladder though, and if that's the case, you can either get a FILL-TROL replacement tank, ( remember, you can't use a standard tank with that fill valve! It HAS to have the plunger!) OR:

Remove the fill-trol valve and tank, and install a new tank...

My suggestion is try adding air to the tank FIRST. Try to get the cold pressure up to 15 PSI by adding air to the tank. I really don't think that November is the time to be ripping into a system if you don't have to. You need heat, not a learning experience! :thinker: