Another banging pipes question


  #1  
Old 12-22-07, 11:18 AM
J
Member
Thread Starter
Join Date: Dec 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
Another banging pipes question

I have a 1500sq ft Cape with a Utica natural gas boiler in the basement. 2 zone heat (UL/LL), Taco circulator, hot water system using fin baseboards. Upper level was recently finished by the previous owner, either with or just after the new boiler (we moved in Jan 06).

Problem is banging in the pipes that service the upstairs zone. I do not hear any noise on the 1st floor zone. It bothers us more now because we have a 7-month old w/ an upstairs BR. Not sure what I need to do to fix this.

I did look at the gauges and it looks like the pressure is about 15 and the water temp was 150-170*. Any help is appreciated.

Thanks!
 
  #2  
Old 12-22-07, 03:33 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 12,682
Received 41 Upvotes on 39 Posts
Banging Pipes

When do the pipes "bang"? Is it when the thermostat shuts down? Do you have zone valves & if so, what kind?
 
  #3  
Old 12-23-07, 06:40 AM
J
Member
Thread Starter
Join Date: Dec 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
They bang when the heat turns on mostly. I don't think they are noisy when they turn off.

How would I know if I have zone valves? I can take a pic of the boiler setup if that would help.
 
  #4  
Old 12-23-07, 07:24 AM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 12,682
Received 41 Upvotes on 39 Posts
Pictures

Pictures are always a help. You can post them for free at www.photobucket.com & provide a link here.
Pix of the boiler & nearby piping.
 
  #5  
Old 12-26-07, 07:39 PM
boilersrus's Avatar
Member
Join Date: Nov 2007
Location: Long Island, NY
Posts: 269
Upvotes: 0
Received 0 Upvotes on 0 Posts
GRADY:

I read your mind. (I took mindreading 101 in school-hehehehe) Water hammer? Not usually the case with Taco circulators and even with zone valves. I suspect with all the construction and remodeling UPSTAIRS where the problem is, the pipes are banging because someone didn't do a good installation (ie. supports, straps, clearances around the pipes or copper, etc...).

I would suggest JFON101231 examines the UPSTAIRS while someone tinkers with the thermostat on and off, to SEE and HEAR where the banging is coming from. Maybe even 'shake' some of those pipes to see what is not supported.

How much may I wager?

BUT, make sure it is when the HEATING system is calling for heat and not when someone is using the sink, shower, toilet, bathtub, etc... because that would be a 'water hammer' situation.

Keep it simple!

Charlie
 
  #6  
Old 12-26-07, 11:41 PM
T
Member
Join Date: Dec 2007
Posts: 12
Upvotes: 0
Received 0 Upvotes on 0 Posts
Similar problem

Originally Posted by boilersrus
GRADY:

I read your mind. (I took mindreading 101 in school-hehehehe) Water hammer? Not usually the case with Taco circulators and even with zone valves. I suspect with all the construction and remodeling UPSTAIRS where the problem is, the pipes are banging because someone didn't do a good installation (ie. supports, straps, clearances around the pipes or copper, etc...).

I would suggest JFON101231 examines the UPSTAIRS while someone tinkers with the thermostat on and off, to SEE and HEAR where the banging is coming from. Maybe even 'shake' some of those pipes to see what is not supported.

How much may I wager?

BUT, make sure it is when the HEATING system is calling for heat and not when someone is using the sink, shower, toilet, bathtub, etc... because that would be a 'water hammer' situation.

Keep it simple!

Charlie
Grady and Charlie:

I had a similar problem. I think it was when the house was heating, i.e. demand for heat. The knocking was in the walls of a 1911 ilk hot water system with a 1950 replacement gas boiler.

I am writing now, because I have ripped it out and putting in a Munchkin 140. I have a question just put up about how to size the circulator. Pump. I have cut down to a 1/12th 100 series B&G, thinking if the water is hot, then it will circulate anyway and with less electricity draw and less noise.

I was thinking, perhaps the circulator was too large. I repeatedly bled the radiators, and didn't find air problems.

If you have thoughts, I will appreciate it. Three floor house with four radiators on first, five on the second and two on the third floors, plenty of windows on first and second floors. About 160 feet longest run from the basement boiler to the third floor radiator and back. Need 14 gal/min for the 140,000 max load.

Thank you.
 
  #7  
Old 12-28-07, 07:07 PM
J
Member
Thread Starter
Join Date: Dec 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
OK, I finally took some pics and got them on photobucket. Here is the link:
http://s269.photobucket.com/albums/jj64/jfon101231/

I don't believe it is an issue with the pipes moving around, which would only happen for 1-2 seconds when it turns on, but I will double check. I did have an issue with that on the pipes to the upstairs bathroom making noise when they were turned off, but a few j-hooks took care of that. Also, the noise is not always consistent nor coming from the same place (sometimes at the MBR radiator, sometimes in the bath radiator, sometimes I can hear it in the walls on the first floor), and sounds more like a bang then something moving around.

EDIT: It is from the heat because I can be in bed at 2am and hear the thermostat click then the banging will start a few seconds later, no sinks or toilets running.

Any thoughts, please let me know!
 
  #8  
Old 12-28-07, 11:34 PM
boilersrus's Avatar
Member
Join Date: Nov 2007
Location: Long Island, NY
Posts: 269
Upvotes: 0
Received 0 Upvotes on 0 Posts
Pipes will move around as long as there is expansion and contraction present, in other words, when temperatures are changing in the pressure vessel (pipe) expansion or contraction will take place until a stable state is reached.

The greatest change in temperature in the shortest amount of time occurs during a call for heat, regardless of which system is being used.

On a call for heat everything expands very rapidly.

After equilibrium is reached, there is no moving around of pipes as long as the temperature still remains constant in the pressure vessel.

When the call for heat ends, guess what, now once again you have a change of temperature. Everything contracts, slowly.

MOST of the noises occur on call for heat, not during cooling down, because [delta temp/delta time] is much greater on call.

Just posting to clarify what actually happens.

I have my trusted and trained snoop dog certified K-9 checking out your pics as I'm typing.

Get back to you soon.

Charlie
 
  #9  
Old 01-02-08, 03:51 AM
boilersrus's Avatar
Member
Join Date: Nov 2007
Location: Long Island, NY
Posts: 269
Upvotes: 0
Received 0 Upvotes on 0 Posts
Nice pictures! Looks like a neat installation too!

Have you properly bled all the air out of the system? If you have, since this is pretty basic, then..........

The only other thing that comes to mind that I did not think about before----------at what temperature are you running the system at? I know you said 170* BUT........IF you are running it TOO high, it's possible that the water is percolating in the system, or even boiling within the boiler.

Without getting too technical about temps. and pressures and boiling points, try lowering your high limit to 170* and no higher. DON'T go by the aquastat setting numbers, usually they are off a bit, better NOT rely on the tridicator reading since you stated it is running [max] at 170*. Use a thermometer capable of reading 200* or so and measure some drained boiler water from the boiler drain AT the boiler. See if that makes a difference. If no difference read on.

We need to determine if the noise is because of expansion or not. So-----for testing purposes only---lower your high limit on the aquastat as low as it will go. This will probably be about 120-140* I presume. Lower your lo-limit on the aquastat to the lowest setting (must be BELOW the high limit amount if you have a lo-limit on your aquastat). Now when the boiler reaches operating temp., try your thermostat to call for heat and see if you still hear the noises.

Make sure that your circulator (pump) turned on when the thermostat called (clicked) for heat.

Any noises?

Let us know what you find.

If you still hear noises and banging, it is NOT the thermal expansion that is the cause.

If there are no noises this time set the hi-limit lower than it was (check with the thermometer) to about 170*. Let us know on a post what you found.

Good luck!

Charlie
 
  #10  
Old 01-03-08, 06:34 AM
J
Member
Thread Starter
Join Date: Dec 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks for the compliments, but we bought the house with the install already done by the PO, so I'm not sure if they purged all the air correctly. I wasn't sure if the zones would be isolated and that is why the air is only on the UL or just because the "bubbles" always rise to the highest point.

Thanks for the clarification and the thoughts. Its too cold today and tomorrow to turn off the heat for too much time with the baby but I'm scheduling this for Saturday and I'll keep you posted.

The more I thought of it last night, I'm thinking it may be the pipes moving, because it seems like alot (but not all) of the noise comes from the wall between the bathroom and MBR...
 
  #11  
Old 01-14-08, 11:05 AM
J
Member
Thread Starter
Join Date: Dec 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
A little more info needed for the rookie

OK, I'm pretty handy with cars, and have soldered etc, but you lost me Not sure what an aquastat or a tridicator is, although sounds like the latter is the gauge that reads temp, pressure, and ???.

I have a meat therm that goes to 220*, so that should work. The only drain I see is right before the circulator, so I assume to drain from there. FWIW, I did see it rise to 190* once when I was in the basement and looked, but right now it is at 170... Not sure if that is normal because I think when I originally checked I waited until after it cycled off...

After I do this, where is the aquastat and how do I lower the hi (and if I have one, the low) limit?

Also, just as a side note, how hot should baseboards get when the water is running through them? At my in-laws I think I would burn my foot, but at our house I can put them right on there bare-foot and they only get warm... This is more true on the first floor than the upper level. Is this due to changes in design or age since the UL is new?

Thanks!

Originally Posted by boilersrus
Without getting too technical about temps. and pressures and boiling points, try lowering your high limit to 170* and no higher. DON'T go by the aquastat setting numbers, usually they are off a bit, better NOT rely on the tridicator reading since you stated it is running [max] at 170*. Use a thermometer capable of reading 200* or so and measure some drained boiler water from the boiler drain AT the boiler. See if that makes a difference. If no difference read on.

We need to determine if the noise is because of expansion or not. So-----for testing purposes only---lower your high limit on the aquastat as low as it will go. This will probably be about 120-140* I presume. Lower your lo-limit on the aquastat to the lowest setting (must be BELOW the high limit amount if you have a lo-limit on your aquastat). Now when the boiler reaches operating temp., try your thermostat to call for heat and see if you still hear the noises.

Make sure that your circulator (pump) turned on when the thermostat called (clicked) for heat.
 

Last edited by Jfon101231; 01-14-08 at 11:07 AM. Reason: Added subject & additional question.
  #12  
Old 01-15-08, 09:05 AM
boilersrus's Avatar
Member
Join Date: Nov 2007
Location: Long Island, NY
Posts: 269
Upvotes: 0
Received 0 Upvotes on 0 Posts
The tridicator is the guage that reads pressure and temperature. I am not sure why the name, but the old ones used to read atmospheric pressure too, maybe that is why TRIdicator? Some models also have a movable RED arrow that is adjustable and in MOST cases should be adjusted to point to 30#. This is only a visual guide and does not do anything to the guage or your system.

You should TEST the water temperature after the boiler reaches HI setting by sampling the water at THE BOILER DRAIN on the BOTTOM of the boiler to get a true reading, not at the circulator.

If you are convinced that the noise is coming from thermal expansion of the pipes, then work on that and leave the boiler alone. Your water temp. at the boiler drain should be 180-190* during heating season, and perhaps adjusted to 150* during the summer.

The AQUASTAT is the BOX with the adjustments for temperature. DO NOT start moving things around until you write down where the dials were originally.

The HIGH side controls the boiler water's set point. The set temp. is the temp. the boiler should shut off at---the HIGH LIMIT.

The LO temp. controls the temp. that will enable or disable the circulators from operating. LOWER than this set point will disable the circulators until the boiler recovers its temp. When the boiler water goes above the LO setting the circulators are enabled and can be operated with the thermostat. when the water temp. is below this set point the circulators will not operated even with the thermostat, until the boiler recovers.

Enough of 'Aquastat 101' and let's go to the videotape.......................

If you want 'grandmas' radiators adjust the temp. to 190* at the boiler drain. Your oil consumption may increase a bit, stay the same, or go down. It all depends. Your radiators will be hotter and the house will heat up faster.

TOO much temp. and the relief valve may pop, the boiler may produce unwanted steam, etc.... BE CAREFUL in this area!

ALWAYS adjust the LO setting AT LEAST 30* lower than the HIGH limit so that you will not disable the circulators.

Grandpa Charlie
 
  #13  
Old 01-15-08, 11:11 AM
J
Member
Thread Starter
Join Date: Dec 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks

I'll look again, but I didn't see any other drain. I hope it is not between the (two) cinderblock supports...

I think it is expansion of the pipes, but I will check the output temp at the drain just to make sure. What is the general rule for clearance when passing through a wall etc.? The house is finished so I'm hoping I can take of this on the UL by removing the covers and making the wall hole bigger etc. and there are no problems on the vertical run from the basement to the UL.

I don't remember seeing a box with adjustments/dials, but I'm sure its around. Is it normally on the bottom by the burner (maybe ref my pic again?

Is less than 190* the "normal" temp? I would like it to heat up faster. We keep it set at 62 overnight and 71 during the day, and it takes about 2 hours to get from 64 to 71...

We have NG so I don't think it will affect oil consumption

Should the LO setting be more than 30* lower than the high? Does it matter if the high is at 180 vs 190? Just trying to "set it (right) and forget it".

You guys are awesome
 
  #14  
Old 01-15-08, 12:04 PM
boilersrus's Avatar
Member
Join Date: Nov 2007
Location: Long Island, NY
Posts: 269
Upvotes: 0
Received 0 Upvotes on 0 Posts
I meant oil on your salad!

Just kidding.

When you are jumping back and forth, at my age, you forget what was what sometimes.

IF the noise is coming from where the pipes enter a cement block or something similar I would line the opening through which the pipes go through with PVC pipe. I am the 2nd McGyver so I would make it this way:

I would cut an appropriately sized piece down the middle (the long way)so I have two halves and slip the bottom one in place and then the top one, and either cement them together or hose clamp them together. ANY liner with a low coefficient of friction between the pipe and the cement would do----maybe you have a better idea.

Many jurisdictions require a single UNCUT piece to line any concrete, cinder block, etc... for oil lines, gas piping, water lines, electrical lines, etc... but not usually through wood.

Short of doing it this way, you would have alot of plumbing to do. Then you would also have to drain and re-fill the system! Alot of work!

When winter is over you can have us all over for a boiler party! Have that MEAT thermometer ready and I'll show you how to cook on the grill. NJT will bring the beers, have the oil and vinegar for the salad ready, and I'll bring the steaks! AND some Long Island potatoes!

Charlie
 
  #15  
Old 03-06-08, 02:23 PM
J
Member
Thread Starter
Join Date: Dec 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
Finally got around to poking my head downstairs. I absolutely do not see any drain(s) other than the ones in the picture by the circulator...

I installed some j hooks etc. in the basement to support the pipes running upstairs, but it didn't help. I double checked where the pipes come through the wall and they have clearance. I'm afraid the issue is in the wall!!!
 
  #16  
Old 03-10-08, 02:43 PM
F
Member
Join Date: Dec 2007
Location: hull, quebec
Posts: 79
Upvotes: 0
Received 0 Upvotes on 0 Posts
hey boilersrus, did you say you keep your boiler at 150* in the summer? so your boiler stays hot year round?
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: