So, I'm here in the house today, the boiler ran this morning for a while, brought the house to 68 from 66 overnight.

Its 1:15 pm EST and all of sudden I hear 2 loud bangs coming from somewhere in house. Sounded like someone hitting metal with a hammer.

It has to involve the heating system.

If I am home, I have started to get in the habit of turning off the circulating pump once the rads have gotten back to room temperature and that is the case here now.

Last fall we replaced the expansion tank the circulating pump and the inlet regulator.
I have a burnham oil fired boiler in a 2 story home.

I wonder if the issue is sediment in the boiler? If that is the case, how do you get it out?

We have generally speaking the regular pings and clangs from the rads and pipes when heating and cool down but these loud bangs are starting to cause me concern.

TIA, Terry

 

Why do you do that? What does your being home have to do with it? Do you turn off the whole boiler system or just the pump, somehow? Leave the pump alone, and just adjust the thermostat - the pump shouldn't run unless there is a call for heat.

 

I turn it off to save on the electrical bill. The pump which circulates the water runs continuously, if it is on.

I do not turn off the pump until the rads have at least returned to room temp, while there is a lot of heat in the system, I let it circulate.

Our house is well insulated and it may only 1 or 2 times during a 24 hour period that the pump is circulating water that is providing heat.

Although not noisy, the rads do have this hum to them, when the pump is running. In one room the rad is close to the bed and it can irritate you after a while.

 

Your pump runs continously, 24-7, even without the thermostat calling for heat? If so, I think there is something haywire with your controls, or possibly your pump relay is stuck closed. I urge you to get your system troubleshot.

But how do you turn off your circulator? If you somehow turn off the circulator while allowing the boiler to fire if there is a heat call or by the aquastat if yours is a warm-start boiler, that is a bad idea.

 

Yes.

I understand they all do, although I read somewhere awhile ago that there is an aftermarket device available that senses the water temp and shuts the pump off at a certain temp.

I turn the whole system off, there is a switch at the bottom of the stairs to the basement. With that switch off, nothing comes on even if a call for heat.

Terry

 

I believe your understanding is incorrect about controlling the pump. The pump can be automatically shut off at the same time as the main burner. Can you post photos of your system and tell us the boiler mfg and model? http://forum.doityourself.com/electr...your-post.html

This should not require an aftermarket device. I'm not aware of boilers that are deliberately set up for the pump to run continously, 24/7. I can't imagine why anybody would want that.

Your turning off the whole system at the thermostat is fine. No problem. But it should not be necessary - and indicates something about your controls is not as it should be, in my opinion.

 

He is not using a thermostat to turn it off. Sounds like the switch to the boiler to cut all power.

 

OK, thanks, I misread that. But, anyway, my worst fears were unfounded. I was worried that he had some way to "turn off the circulator," and let the rest of the boiler run.

 

I remember that Terry has been here before... and I sorta remember that his system was wired up to run the circ 24/7 for some reason or other... I'm gonna hunt back and look at some previous posts.

No... I just read back and I don't think we were ever aware that the pump was on it's own circuit and not switched by the boiler controls...

 

Hi Trooper:

Here is a pic of the unit in question. Now tonight it ran and not a peep out of it, other than lots of clinks and clanks from the rads, after they have cooled and you walk by them.

Its a burnham boiler 1998 vintage fired by oil.
its a pv73wz tbwf3 model v-7 series.
D.O.E> ht. cap. 121 mbh is what is says on the tag.

http://img541.imageshack.us/img541/3889/boiler1.jpg

T.

 

OKAY, now I'm officially confused.

The gray box at the upper left of the boiler, you know that's your aquastat. The circulator is wired into that box. Is it wired to C1 and C2 terminals inside?

By the way, you really oughta fix them wires hanging outta the circulator like that.

 

You have a boiler bypass piped up on your boiler... is that valve open or closed?

 

The by pass valve is fully open.

I will confirm the wiring in aquastat once it shuts down.

Yes, the wiring is on the hit list, I will do that today...T.

 

back again.

white wire from circulating pump goes to c2
The black goes over to I think its 3. C1 nothing is connected.

Hopefully the pic helps.

http://img198.imageshack.us/img198/3189/aquastat.jpg

Thanks, Terry

 

It does help... but I'm sitting here trying to second guess your installer, wondering whyinthehell he wired it for constant circulation... there must have been some thought process involved, he must have had a reason... pourquoi diable aurait-il le faire?

If you remove the jumper from 3 and put the black wire from the circ on C1, the pump will only run with a call for heat, and shut down when it was done.

I don't want to advocate making the change without knowing the reason it was done like that though... since it's obviously a high water volume system, probably cast iron rads, judging by the size of the original piping, I wonder if they had some concern for 'thermal shock' to the boiler casting?

What speed is the pump set on?

I would use a 90° sheathed cable connector for the wire entering the circ.


image courtesy monumentalelevatorsupply.com

and there should also be a 'redhead' insulator bushing to protect the wire from being cut by the metal sheath. These get inserted around the wire inside the metal sheath:


image courtesy drillspot.com


image courtesy frostelectric.com

 

I would think that shutting the circ pump off right after a long boil would waste a lot of the heat in the system.

I've seen, somewhere, a system that turns off the circ pump after the water has reached a certain temp. Having the pump run 24/7 is wasteful, that is why, when I'm home, or remember to do it, I turn it off If I determine the system won't be required for awhile.

As long as there is not some hidden problem that I may be causing by shutting the system off manually, I will do that until such time as I research the automatic system.

My neighbour is a master electrician and loves to right electrical wrongs, so I will show him the issue.

But what of the banging and clanging going on with the system? There are some alarming banging sounds from it now and then.

Another issue, for another day is having the asbestos wraps removed from the pipes in the basement. Someone mentioned to me to have it removed and to leave them unwrapped and the heat from the pipes will help heat the basement and the floor above.

Terry

 

Maybe mine? I took a queue from EK ... I added a second aquastat to a well on the boiler which is wired between 3 and C1, as your jumper is. When boiler fires the circ turns on normally but when the water reaches about 125-130 it closes and bypasses the relay in the a'stat. Then after the heat call is completed, the circ will run until the water cools to appx 115-120 when the added a'stat opens and the circ shuts off.

The only possible problem with this is that the room may overshoot the setpoint of the room t'stat. I have only one zone, and the thermostat is a 'semi' intelligent model that 'learns' when to shut the boiler down in ANTICIPATION of the overshoot. If one had a high water volume system and cast iron, I don't know that even the thermostat would be able to compensate for this overshoot.

Yeah, we have kinda gotten away from that... have you heard it again since your first posting about it?

Are you sure it's the "A word" ? It's true that it may heat the basement a wee bit, and possibly the floor above, but keep in mind that heat radiates in ALL directions, from warm objects to colder objects. That's what's called 'driving force'... the colder the distant object, the more force the heat rays exert in trying to reach that object (or space).

Yes, a portion will drive upward and heat the floor. A portion will heat the walls and floors in the basement. A portion will be lost to the earth.

I personally would rather save the heat for the living spaces.

 

I'm back, got busy there....

The banging sound is still there, although it seems to be more prevalent as the system is cooling down after a firing.

It is really difficult to tell where it is coming from exactly, so kind of hard to analyze it.

The rads make a lot of popping and what I describe a tinking/thud noise. Some of the big rads really startle at times, because they do it when you are walking near them. Our house still has the original 85 Y/O hardwood floors, so I imagine a little deflection is causing them behave that way, just a theory.

Yeah, I'm pretty confident that it is the A word.
I'm going to have it removed eventually, it will give me a little piece of mind and it will help the re sale value.

Thanks for all the help, I appreciate it.

 

Just heard that big bang now. 2 of them bang bang. second bang not as loud as the first. I'm upstairs and it sounded like it came from the hallway up here where there is a rad.

The boiler has been off for about an hour now, circ pump is still running.

t stat set at 68, although, when I got home the temp in the house was 64, so the boiler was running for awhile.

 

IT could be that the pipes aren't well secured and when they contract during cooling, there are a couple places where they get a good bang. My system will bang a pipe as well. It's not really loud though.

 

That type of sound is usually due to a pipe rubbing on a wood part as the pipe expands. It's like a very very very low frequency violin... if you are able to localize it, you might get lucky and find where the pipe is 'hanging up' and slip a plastic shim between the pipe and the wood. The problem is localizing the sound because it's going to 'telegraph' through the whole system.

 

Were you referring to my noise or the OP's? For me it's definitely a bang. I was saying is wasn't that loud compared to what the OP described. You can hear it just fine, but it won't startle or wake you up at night. It might actually be pipe on pipe.

 

I have those approximate 8" cast iron baseboards all around my house. I used to hear that samel4 oud banging noise when the cast iron baseboards would heat up or cool down. The longer they were usually translated into a louder bang. They were originally installed right onto the hardwood floors. As I gutted and re-did each room, I solved the problem by placing 2 small 0.040" pieces of aluminum sheet under each foot of the baseboard. On one surface of each piece of aluminum, I placed a piece of teflon tape, the sandwiched the 2 pieces together before placing them under each foot. The Teflon tape provides a very low friction bearing surface and allows the baseboard radiator to expand and contract freely without jumping across the floor. Since I also redid the plumbing to each, I made sure each pipe was secured by a bracket, but with a small piece of pipe foam insulation around the pipe and under the pipe bracket. Where the pipes came thru the floor, I made sure there was enough clearance around the pipe so the pipe wouls not touch the wood.

Ever since, it has been very quiet.
I am sure you will not go to these lengths, but if you have access to the pipes, follow them around to see where they are secured to floor joists to see if you can do something to correct some of the noises. Mosy likely, you will not be able to slide something under the feet of each baseboard.

 

Thomas, you might be onto something....

I don't have the rads like you describe, mine are monsters. I have 3 on the main floor that are about 40 inches high x 5 ft long, they must weigh at least 500 lbs each when full of water.

They have, over the 85 years or so they have been here, become quite intimate with the floors on which they rest. Certainly I have seen worse, but mine have settled into the floors about a 1/4 to 3/8 of an inch, creating a binding effect if you will.

Not that they likely ever did slide across the floor as they expanded and contracted, but being locked down like they are now must be a factor to the banging and clanging?....as an aside, I have kind of gotten accustomed to the noises and expect them now....but, my wife, still about jumps out of her shoes when they do and always asks, "what's that noise?" She's so cute like that I can't resist her.

 

Then why on Earth would you want to 'fix' it?

When I read Thomas' solution, I thought to myself "that is brilliant!" that's much 'slicker' (pun intended) than my personal choice of cut up plastic milk bottles.