Being from the south, boilers and baseboard hot water are new to me so excuse all the inaccurate descriptions. But that's what I've had in my New England home the last two years. Everything has been fine until just recently. Let me first describe the system:

Burnham series 2 boiler (natural gas) with Taco 007 circulator.(see pics) Four heating zones in my 2500 sqft 2 story colonial. One in basement with the boiler, two on first floor and one upstairs.

I think I've always heard a bit of a trickle in the pipes when a zone calls for heat, but two nights ago we were awoken by the loud sloshing of water upstairs. Louder than it had ever been. (I assume this is a lot of air in the system?)Then last night when the heat was turned on, upstairs never got hot at all. I turned on the two zones on the first floor and they both worked fine.

I read these forums for a while today to try to learn a little, and when I got home I turned up the heat again (only upstairs) and waited/watched. I first hear the circulator buzzing, then the burner fires up. The temp rises, but the outpipe for that zone never really got hot past the taco zone valve. The pipe up to the expansion tank got really hot. And surprisingly, the return pipe (going IN to the circulator) got really hot too. I'm thinking this was hot water backing up from the boiler, not circulating through the house.
So, no hot water upstairs again, (even after manually opening the zone valve) but there was a lot of sloshing around i heard in the basement zone, and the occasional creaking/trickling at the pipes right at the boiler.

The only thing visibly questionable is the air purger after the expansion tank. It's rusted, but it's not wet. Looks like in the past water has leaked from the top? Nothing is actually wet. Again, see all the pics.

So, where do I start? I'm 99% sure there are no bleeder valves in any of the zones throughout the house. Should I be bleeding it somewhere else or troubleshoot something else entirely.

Here are the pics - please let me know if I can provide more info. Thanks!
http://i253.photobucket.com/albums/h...r/IMG_2278.jpg
http://i253.photobucket.com/albums/h...r/IMG_2282.jpg
http://i253.photobucket.com/albums/h...r/IMG_2288.jpg
http://i253.photobucket.com/albums/h...r/IMG_2284.jpg
http://i253.photobucket.com/albums/h...r/IMG_2285.jpg
http://i253.photobucket.com/albums/h...r/IMG_2287.jpg

 

If you hear water sloshing about you don't have enough water and you have air in the piping.

First, look at the pressure and temperature gauge on the boiler. The pressure should be about 12 to 15 psi when the system is at room temperature and higher (although not much above 25 psi at the highest) when the system is hot. If the pressure is not between 15 and 25 when the system is hot then you need more water and you will likely need to get rid of air.

Your system probably doesn't have individual air vents on the baseboard convectors because I see purge valves on the return piping. You need to get on the step stool and check the little cap (tire valve cap) on the top of the float air vent that is on top of the air eliminator. The cap needs to be loose to allow the vent to work properly. If it is tight and when you loosen it water squirts out you need a new vent.

Get back to us with the pressure and temperature gauge readings and we'll go from there.

 

Hmm...I'm thinking this can't be good....



The cap on top of the air purger was loose, though.

 

No, it ain't ...

Since you already have Zero PSI in the system, it is a perfect time to check the air charge in the expansion tank.

Remove the red plastic cap from the bottom of the expansion tank (EXTROL). Using an ACCURATE tire pressure gauge, check the pressure in the tank. It should be between 12 and 15 PSI. If it is not, use a bicycle pump, or a small compressor to add air to the tank until it is.

If any water comes out the tire valve, the tank must be replaced before you go any farther.

All the air you put in that tank should STAY in the tank... if you hear what sounds like air bubbling up out of the tank into the system, and you pump and pump and can't build any pressure ... the tank is bad and needs to be replaced. It has a ruptured bladder.

Follow the water feed pipe into the boiler ... you see that brown bell shaped thing above the boiler? that's yer feedwater pressure regulator. Below that is a valve with a red handle on it.

BEFORE YOU OPEN THAT VALVE, SHUT OFF THE BOILER AND LET IT COOL TO 100° OR LESS! You can crack a boiler by adding cold water to a hot boiler! Then, check that valve is open. If it is closed, open it and watch the boiler pressure. It should come up to between 12-15 PSI and level off. If it rises above 15 PSI, close the red valve again. Your regulator isn't controlling the pressure properly and probably needs replacement, because it's 'leaking' through.

If the valve is already open, your regulator is probably plugged and not letting water in to the system... again, probably replacement time.

So, first thing, check the expansion tank while the boiler is at zero PSI, second, try to determine why there's no water in the system.

BTW, that gauge cracks me up ... who ever heard of SIX degrees per division? that's sick...

 

Wow - thanks for all the info, Trooper. I'm going to try all these things when I get home tonight.

So its starting to make sense....the system SHOULD keep the same amount of water in the pipes at all times by way of that pressure regulator, right? If the system loses some water and the pressure drops below 12psi, that regulator should open up and feed water until psi is in that 12-15 range? If the regualtor is bad, is that a Home Depot thing?

I hope this isn't a dumb question, but I suppose just turning down all the t-stats for the day should cool everything down enough...if there's another way, let me know!

And yeah, that 6 degrees per tick...I thought that was strange. But it must be a "boiler thing", or something. hehe.

I'll report back later...thanks again.

 

Exactly. If that thing is working properly, the pressure in the system will never go below it's 'setpoint'. System pressure obviously can go above setpoint. The amount it rises depends on the expansion tank sizing for the most part. Less tank, more delta P , and vice versa.

Usually ... Watts ... 1159 ? or is that the number for the 'combo' unit that includes the 9D Backflow preventer ... which BTW is required by code in many towns on any new installations. It's a good idea really ... if you do have to change the valve, might consider adding one to your system.

Yes, that would do it... but there should be a big red switch somewhere ... most folks call it the 'emergency switch' ... you can turn that off too and the boiler shouldn't fire. Or, if it's on it's own circuit (ought to be), you can flip the breaker off, and 'tag it out' ... make sure you tell anyone that might turn on a switch though, that you are working on it... maybe the breaker is a better choice...

Phroberry rost sumsing in transrayshun!

 

Well, before I even got to the regulator, the expansion tank is giving me problems.

I pried off the red cap, unscrewed the valve cap and a drop or two of dirty water ran out. There was no pressure in the tank, so I went ahead and filled it to about 14psi. I can now hear air very slowly escaping from that valve and see an occasional splatter (more like a "spit") of water.

If this is like a standard schrader valve on a bicycle tire, can I not just replace the valve core? Or do I need to replace the whole tank?

 

Yes, it's a standard schrader valve core ... but here's the thing... if you've got water on the air side, that means that the bladder in the tank has got a rupture in it ... tank needs replaced ...

That red plastic cap didn't need to be pried off, it would have unscrewed.

 

Boy, do I have a lot to share...

Last Thursday I found out how I got all that air in the system and why there was no pressure. One of the heating zones (a little room off the basement, never used) burst a pipe the night before. Water everywhere. Luckily, it's 1st floor, tile, and a bunch of rugs/blankets had soaked up the water.Almost no water damage.

Then that night we lost power due to the ice storms in NH. 5 days later (Tue night) power was restored. I had a small generator and our pellet stove kept the house from freezing, so I was lucky there.

Wednesday, had plumbers come by and repair the broken pipe (and replace expansion tank while they were at it). They put antifreeze in the system which should prevent this from happening in the future. So power's back on, boiler/heating system is back online and all is back to normal. What a week!

Thanks for all the helpful advice. Even though I wasn't able to repair it myself, I now know a lot more about how my heating system works. I think I can quickly diagnose any future problems now.

Thanks!

 

Great... a happy ending to a harrowing week+. I'm glad to hear that.

Sounds like the glycol was a good idea... it should be monitored for PH periodically, so keep that in mind. You could do that yourself with a cheapie test kit I think.

 

Wide-range pH test paper. Should be available at a swimming pool supply. You also want to periodically test the percentage of glycol in the system, especially if you leave the make-up water valve on. I like a refractometer but they cost about $50 to $80. Harbor Freight sells one as a combination anti-freeze and battery charge indicator for less than $50. Harbor Freight Tools - Quality Tools at the Lowest Prices

Ideally you would test the strength of the corrosion inhibitor too but that requires knowledge of "what" corrosion inhibitor was used in the formulation.

 

Wow - what a great thread! I had the same water flow / trickle noise inmy pipes. Went down and looked at the guarge - pressure was about 5 psi. Also, the makeup water ball valve was closed! But I opened it slowly, while the boiler was running, and the pressure came up to 20 psi. I also checked the expansion tank pressure, which was low (10psi) and upped it to 14 psi. Now hopefully the waterflow noise is gone.

One question - how does one bleed the system of any air?

 

Pictures of the boiler & nearby piping would help. You can post them on photobucket.com or similar site & provide a link here.

 

I have a system very similar to jdmclemore. I had been hearing whooshing sounds in a few of my zones and decided to read here in the DIY forums to see if anyone else had posted similar issues. Then I found this thread...excellent info!

My pressure tank had little/no pressure in it and I raised it to 14psi. The air stayed in the tank...no air bubbling sounds. BTW, when I put a pressure guage on the schrader valve, the small amount of air that came out smelled disgusting.

I do have a question for you: My feedwater pressure regulator is in line differently than jdmclemore's. My cold water supply goes like this:

cold water supply > valve > feedwater pressue regulator > return piping (w/air purge valve)

My cold water supply valve was CLOSED. Should I keep it closed or keep it open?

Here's a photo:

 

Automatic water feeders (pressure reducing valves) are a double edged sword unless you have a low water cut off safety installed. If you do have a low water cut off (LWCO), I suggest leaving the valve off.
If you don't have a LWCO, this where the catch-22 comes in.
Leave the valve open & possibly mask a leak. A lot of fresh water coming in will rust out a boiler; close the valve & if there is a leak, take a chance on damaging the boiler due to low water.
Best solution: Install a LWCO & close the valve.

Any numbers on that "pressure regulator"? The handle on it looks more like one on a relief valve than a reducing valve but the bottom looks like a reducing valve??????

 

On the left side it is stamped "B3"

On the right side, it is stamped, "CASH ACME"

 

That valve is a reducing valve not a relief valve. The handle shape threw me. Thanks for the pic & numbers.

 

I'm still getting air or "swoosh" sounds in my baseboards. Any ideas?

 

The cap on the air purge valve should be loose so air can escape. Any air bleeders on the baseboard ends?

 

I'm new to this forum, so I hope I'm not being intrusive here.

I have a hot water system similar to the ones described above, but older; I don't see an air purge valve. I'm not sure how professional the installation was, but it seems to me that is an important part, right?

Also, in trying to bleed the air from the system I have added a lot of water, so I'm wondering about cleaning out the system and/or adding chemicals. I can't get anything into the expansion tank since it is a 25 gallon tank in the rafters with only a faucet on the bottom.

Thanks for your help. I've enjoyed reading the discussions here.

 

The fact you have a conventional tank with no air bladder dictates NOT installing an auto vent (air purge valve).

 

Dennis, how's the system pressure? Does it run around 12-15 when cold, and maybe low 20's when hot?

Have you (or anyone) ever drained the expansion tank?

If you post pics of the system, we might be able to look them over and offer some suggestions... free account at Image hosting, free photo sharing & video sharing at Photobucket ... upload there, provide link here to the picture album page...

 

Hope you're having a good holiday!

Nothing urgent about this; the system is working; I'm just worried about the long term prospects.

Here's a few pics:

dennislee - Photobucket - Video and Image Hosting

I hope that link works.

To answer your questions:

1. The pressure was at zero, and I determined that the pressure regulator valve was faulty, but haven't yet replaced it.

2. I added water via the drain valve to get the pressure to 15. It stays there, without much variation, whether cold or hot.

3. I did drain the expansion tank (about 7 gallons).

Thanks for your attention!

Dennis

 

What kind of emmiters do you have (baseboard, cast iron radiators, convectors)? Check the ends of the emmiters for small manual bleeders. Most need a special key to open but some you can use a screwdriver.

 

I have baseboard heat. One contractor took off all the bleeders, and told me to bleed with valves he installed in each loop from the basement. I added a picture to the photos:

dennislee - Photobucket - Video and Image Hosting

It seems fairly effective, but requires a lot of new water each time.

Dennis

 

The way that expansion tank is piped will not allow any air to find it's way back to the tank... that's what's supposed to happen... air circulating in the system should be able to go back into the tank.

Since it's got that 'trap' on it, it can never get there. In general, it's good practice to use 3/4" (yours looks like 1/2", but pics can be deceitful) and have it slope upward about 1/4" per foot, all the way back to the tank. I suspect someone at some point got tired of banging their head on the pipe and thought that would be a good idea... it's not.

How/where does the pipe to the tank connect to the rest of the piping?

 

You're right, it's 1/2 in., I included a pic to show where it's connected (Sorry it's rotated)

The pipe is coming from the hot water pipe from the boiler.

dennislee - Photobucket - Video and Image Hosting

I hope it's clear. The tank is about 15-20 feet from the furnace so it's hard to get it all in one shot. It does seem to slope up except for the trap.

 

In that case, I wouldn't worry about the 'trap' at the tank, cuz the way it's connected to the boiler isn't going to allow much if any air back to the tank anyway.

Your only choice seems to be using the bleeders on the radiators... and accept the fact that it may be a 'constant' thing. A more permanent solution would be to have some type of air scoop installed near the boiler, and the expansion tank connected to the top of that to collect the air and send it back to the tank, where it belongs.

 

Thanks, I'll look into the air scoop idea.

Should I worry about all the new water I'm putting into the system? Anything I can do about it?

 

Try to keep the addition of fresh water to a minimum. That's one reason I prefer individual bleeders to purge stations. If the baseboard is installed properly, with a slight pitch, & the bleeder is on the high end, air will want to go there anyway making bleeding easy.

 

I saw somewhere a description of how to clean a system, then add chemicals to control the pH. I'm guessing that's not really possible with this type of system.

 

Usually hot water residential systems are left alone in regards to water treatment. As long as you are not adding fresh water the water in the system becomes "neutral" neither leaving any more deposits nor attacking the metals in the system.

 

OK, I'll try to avoid putting more water in!

Thanks for all your help!

Dennis

 

In regard to the air scoop:

The supply pipe is a 1&1/4 inch vertical pipe that goes straight up to a T (with that 1/4 inch pipe to the expansion tank off to one side)

dennislee - Photobucket - Video and Image Hosting.

I'm guessing that an air scoop needs to be on a horizontal pipe, so do I need to put a loop into the vertical to make this work?

How important is is to collect the air and send it back to the expansion tank? Seems like a difficult proposition.

Thanks,

Dennis

 

Rather than trying to recycle the air, it would be a lot easier to simply do away with the existing tank & install a bladder tank.

 

That sounds like a good plan!

Where would be the best place to plumb that in?

Would I still need an air eliminator of some sort?

And where would that go?

 

Does the supply come straight up then split equally at the tee?
Return is piped the same way?

 

Yes, both up straight and then teed.

Make-up is plumbed to just below pressure relief valve at top of boiler.

 

A horizontal section of pipe is required for the air separator. There are a couple types... some require 18" of straight pipe ahead of them... others don't.

If you convert to the bladder tank, you also need to add an air scoop. The cast iron type have a tapping on top for an automatic float type air vent... and a tapping on the bottom for attachement of the expansion tank. The tank will hang from this connection, so you need room below...

The tank doesn't HAVE to be installed at the air scoop. So, you might have to install the air scoop in one location, and the tank in another.

It's actually probably LESS work to add the bladder tank, because you won't have to re-do the piping to the old one ...

I need to look at your pics again ... might need more pics ... let's see... back soon...

 

The tee makes it difficult & almost requires two air scoops.