Only one baseboard in zone working

1_cold_Kid

Hi All,

New to the wall and definitely not a plumber.  I have a problem with non working baseboards on a forced hot water system.  We had an addition done 5 years ago and have had the following problem since day 1.  2 zones were added to the existing system.  In the furthest zone, the baseboard in bedroom 1 heats up just fine and the room is toasty.  The baseboards in bedroom 2 and a short baseboard in the hallway are always ice cold.  We've had the plumber back multiple times with no resolution.  He's said it's an airlock, the pipes are on an outside wall, and there's nothing wrong.  The system has been bled at least 3 times.  There are no valves that I can see on the baseboards.

The airlock idea seems possible but that should have been resolved by bleeding the system.  Also, can the first baseboard in the zone heat up fully without the others heating up as well (doesn't the water have to flow through all of them to return to the furnace?)?

Any ideas?  Suggested direction going forward? It's been a mild winter so far but that's changing.  I need to get this room heated for my daughter.  Thanks.

JK_3

Need more info

I s this a continuous loop system or a venturi type system? can you see the piping connected to these baseboards ? can you post photos ?

There are many configurations of piping and each one behaves differently. With out more info it is very difficult  to help you, If you follow the piping from one of the baseboards what do you see ? Are there tee fittings going to the next baseboard or does the pipe just go directly the next baseboard ? Have you checked that there are not bleeder fittings at any point on these baseboards? How are you bleeding the system? Is the person trying to bleed it the same person that installed it ? Pictuers of the boiler , the piping near the boiler, and the baseboards(old and new) would help. If you cant post pictures then try drawing the boiler and related piping so that we can try to help.

Jean-David Beyer

This is not my problem, but it could have been.

When were venturi type Ts first an article of comemrce? My house has two baseboard heated rooms that are part of a single loop. The pipes are buried in the floor and I would have to rip it up to be sure if I have them, or if they are just connected in series. One gets hot before the other, so I guess they are just in series. The house was built in 1950 or perhaps 1951. The two rooms heat just fine, so I do not have to fix anything, but I am curious. If these things were invented after the house was built, it would settle this.

icesailor

Mono-Flo/One Pipe Fittings:

Venturi Tees go back way before your house was built.

More than likely, the loop was split and the other non-heating loop isn't able to be purged or vented properly. Unless the piping is wrong, there is no way it shouldn't work.

I think that the above person needs new eyes to cast their vision upon the problem. Obviously, the installer doesn't know how to resolve it or what is wrong with it.

What is that definition of "Insanity"? Doing the same thing over and over and expecting a different outcome?

1_cold_Kid

pics attached

Thanks for the rapid response.  I'll try to answer your questions and have attached pics of furnace and piping (sorry for two pics - cramped space).  The horizontal pipe in the top right corner goes to a ball valve but was cut off in the pic.

I can't see the piping for the affected baseboards but did go in the crawl space to see how other rooms in the addition are piped.  No T's that I could see or feel.  I remember two pex pipes coming up for each baseboard and assuming that the baseboards in each of the two new zones were plumbed in series.

Didn't know what venturi means but looked it up.  Still not sure but what I read seems to describe how the old, and still functioning, radiators in zone 1 are plumbed.  There are T's on these and, if I remember correctly, have a feed pipe and a return pipe that each radiator ties into rather than technically being in series where water goes through one to get to another.

I've bled the old radiators numerous times in the past by turning the screw at the top and allowing air and water to escape until it is a steady stream.  I've also had the installer bleed the system two or three times at the furnace (a friend also tried once in between installer's attempts).

Return valves seem to work fine for all three zones.

Can't take the covers off of the new baseboards right now because kids are sleeping.  Don't see any visible bleeder valves anywhere and distinctly remember a family member commenting on that after the install.  Mentioned it to installer and he said they weren't necessary.  I'll check again after work tomorrow though.

And yes, it is absolutely time for other eyes.  This entire project's been a nightmare. Just trying to educate myself so I don't get hosed again.  I truly appreciate the help.

 

Alan Welch

Zone valve problem?

It appears  that you are zoned with zone valves sharing a common  circulator , On each zone valve there is a little silver lever alongside the wires . When you turn up the thermostat the zone valve should open  and the lever should move easily. It is possible the valve is not opening and the baseboard that does heat is on a different zone.  If you know which zone valve you can manually open the valve with the lever and it should heat when either of the other zones are heating.

Paul48

purging

Has any of the attempts at purging resulted in the baseboards working at all? If all the plumber could do, was identify the problem and not resolve it, it's time for a new plumber.

icesailor

Purged:

From the photos, there is no reason that the system wouldn't run. Venting air at the heat emitters is a waste of time. It needs a good purge by someone who knows how to do it.

However, make sure that the zone valves are opening all the way and they start the burner and circulator. That boiler and install isn't all that old. Is the boiler high limit set too high and because that circulator is placed in the location Du Jour, did it "lunch" from hot water and need to be replaced?

If the fill is in the location Du Jour, and you purge it, and the fill water doesn't go through the boiler, you will never know when it is purged and hot water is coming back. When you "purge", you can ONLY have the zone valve calling on the zone you want to purge. If another zone is open, it will take the path of least resistance and you won't get the air out.

JK_3

Venturi ?

The two pex lines comming from each baseboard connect to what? Does it go directly to the next base board or do the connect to a common pipe with tees?

1_cold_Kid

getting new eyes on problem

Thanks for the feedback. 

Yes, the circulator has been replaced once. (nice call)

I watched the purging pretty closely once and believe it was done one zone at a time at the boiler.  All attempts tp purge were done at the boiler.  I've bled the old radiators a few times.

There are no T's in the affected zone although there are in another zone. 

I believe the pex goes from one baseboard to another.

I've thought about the idea  that the cold baseboards are on a different zone.  I've turned off all zones and fired up each individually.  The cold baseboards never show any signs of heat at all no matter what zone is operating.

The zone valves are all working.

Lastr night I went into the crawl space that all pex runs through before running up through the walls. When the affected zone was the only one running I could feel two hot pex lines (assuming one is the feed and one is the return).

I just don't get it.  It's like the two cold baseboard aren't tied into anything.

I am going to contact another heating company once pay day rolls around.  I'll post the resolution if there is one.

Thanks again for the feedback!

Harvey Ramer

Just for kicks and giggles

take the front cover off the affected baseboards and make sure the fins aren't full of dust and stuff. The air needs to be able to flow freely through the baseboard.

Gary_17

The baseboards are probably teed

after the pex leaves the crawl space. If it were a continuous loop and both the supply and return pipes are hot there is no way all the baseboard couldn't be hot. The hot water is just taking the path of least resistance back to the boiler. There will probably have to have some type of air bleeders installed on the baseboards to get the air out and then they should get hot. Is it 1/2'' pex? If it is I wonder just how many BTUs you can shove through it to even get to the baseboards.

icesailor

Purge It:

OK,

The PEX zone is the one that doesn't work. You said that it was hot at both ends? Supply and return? Trace that back and mark them with red and blue tape. Red for supply, blue for the return. Your supply is the side with the circulator on it. The return has the zone valve. Turn the PEX zone thermostat all the way up. Turn all the other thermostats down as low as they will go (Off) Check to see if the lever on the side of the valve goes easily all the way down. Close the valve where the return goes back into the boiler and put a short hose on the draw off. You need a 5 gallon bucket. Check the pressure reducing valve/fill valve. Check the system pressure. If it isn't 15 #, it's too low. Raise the bypass lever and raise the system pressure to 25#. Open the drain valve and drain the water into the bucket. Put your hand on the copper pipe. You should feel the temperature changing. If it starts to get cold, you are being successful. Let it keep running with the bypass open. When the water starts to get warm, you should hear rumbles and thongs as the air bubbles come. When the water starts to get really hot and the hose isn't dancing, close the fill valve bypass and close the purge drain. Open the ball valve and the pump should make it flow.

Someone mentioned a Tee. If it is split, only one side may work. If you have that problem, write back.

If the pressure in the system is low, like around 10#, raising the pressure to 25# might make it start working. It needs a good purge.

Alan Welch

Probably right

That  the 2 bedrooms  are not tied into anything but themselves.   3 sections of baseboard =6 drops into the crawlspace, sounds like who ever looped it together looped the wrong drops, but the best way to prove it is another trip into the crawlspace..  

Alan Welch

Probably right

That  the 2 bedrooms  are not tied into anything but themselves.   3 sections of baseboard =6 drops into the crawlspace, sounds like who ever looped it together looped the wrong drops, but the best way to prove it is another trip into the crawlspace..  

icesailor

Dropped:

I don't understand.

You have three radiator sectiions. How many drops do you think you need?

Did you purge it like I suggested?