Annoying whistling in pipes

llockett

I have a Laars Boiler for about 3 years now however 2 days ago it started to make annoying whistling noises. I went to put my ear to the unit and hear the whistle but can not pin point it. If I go upstairs and put my ear to the baseboards, I hear it. Should i drain the boiler in case of air pockets? This is all new, no changes were recently made or nothing. The whistle is surely not steam sounds. Thanks please help

Paul48

Don't drain the boiler. Call a professional to troubleshoot and fix the noise. Most likely a bad circulator, but needs hands on.

jonny88

Had a whistler today,check valve in circ had some debris in it.

llockett

I apologize however I am not knowledgable towards boilers at all, may I ask where and which valve you are referring to or and where is it located, thnx

billtwocase

You might want to add that to the above post johnny88. The thread about the "advantage" of IFC circs. Don't like them for just that reason and more

Paul48

llockett........... In my experience, if you let this go, it will fail in the middle of a blizzard, or Christmas Eve. If it was April, you could begin learning about the system, and we could walk you through repairing it. Every system is different, and requires handling in a specific way, based on its characteristics. I wish we could tell you how to simply fix it yourself, but we can't.

llockett

Hi all well after about 2 months the whistle still remains, to the point that my wife and I go to the Hotel for rest due to the loud humming throughout the pipes. We had NJ boiler techs come out 5 times with 7 techs and still no resolution. The boiler is only 2 years old, they changed the gas valve, the burners and I had gas company come out to correct the intake gas pressure....I am totally lost. I am desperate for advise....we looked at the heat exchange and it looks good however would you think that needs changing or cleaned? should I pour a solution in the attempt to clean the unit although its only 2 years old? Thanks

nicholas bonham-carter

who are these boiler techs, who are having such trouble with this?
this more than any cleaning can accomplish.
what needs to be done is the sequential disconnection of one pump or valve after another until the noisy part is located.
obviously, this will have to be done in a certain order to prevent the system from shutting down before the test is over.
the manufacturers rep for the boiler may have a part to play in this.--NBC

llockett

Hi Nicholas, these are certified NJ Gas Co. techs. Ok thanks, the pump is good because as the system shuts down I can hear the pump shut off but the whistle stays and slowly fades as the unit shuts off....do you think I have a Heat Exchange issue? on such a new unit

nicholas bonham-carter

that lingering whistle may give a clue.
call the manufacturer, and see if the local rep can get involved with this.--NBC

hot_rod

Could be the hx is limed up a bit on the inside. I've heard them whistle, moan, percolate, even jump around when the heat energy is not getting to the fluid due to a thin build up.

My go to product was Hercules Sizzle, run it for a day and flush as per directions.

Check and make sure it isn't taking on fresh water due to a leak of relief valve discharge.

llockett

Thanks Nicholas and Hot Rod, appreciate your time and attempts, well it was another terrible night as this tea kettle whistle kept the entire family up all night....NJ Gas company has told me that they pretty much don't know what it is, the boiler is good " 2 years old" and its pump is great but they just can't find whats vibrating that very annoying loud whistle / humming throughout the house. Hot Rod due to now having 8 techs to the house, I will like to try this myself...I picked up the Hercules product but I am not sure how to start, Where do I insert it? must the boiler be cooled down first? do I use the entire bottle? Should the boiler run all day while the solvent is in it? please help us, we need some sleep my friend. I don't know where or how to see if its taking on fresh water but I can snoop around...Here is a link of my boiler

https://www.youtube.com/watch?v=3xxMcUglqcE

http://www.homedepot.com/p/Hercules-1-qt-Boiler-and-Heating-System-Cleaner-35206/100207068

hot_rod

Directions on the bottle say 1 gallon per 30 gallons of system fluid for water heater cleaning. Not knowing what you have for fluid, maybe 1/2 that.

It is a closed loop, pressurized system so you need to pump or inject it into the system, or drain down the system and pour it in.

Best to inject it so you don't drain down and air lock the system.

You will need tools and a bit of knowledge how to drain off some pressure and fluid to add in the cleaner. A small drill motor pump will work.
Remember you are dealing with acid here, you need to be very careful, have safety glass, old clothes, etc.

It might be worth getting a pro one more time that has the tools and some experience with drain down, fill, purge, flush and refill.

Sorry about the headaches, that is not an uncommon noise in copper tube HX if they have flow limitation from some cause. Generally if it worked and was quiet for a few years, then it's a problem that have been slowly developing, like scale build up. Sort of like plaque on teeth

Are you sure that circ pump is sized correctly? Copper tube heat exchangers want a lot of flow to scrub out heat and keep the tubes clean. Laars should be able to advise you also.

llockett

Thanks Hot R. ok I think I will call in the techs again, besides...I am paying a monthly service charge for such type issues...I called Laars and they were no help at all....they pretty much said they do not support residential unit owners....I think the pump is good being that it did us justice for the majority of the 2 seasons, this specific sound came instantly 2 months ago in the midst of the night "from no where" However I do admit that during that time my Hot Water heater went bad...not sure if that has something to do with it...but again this whistle came about before that point...I drained a little water from the unit and its very clear looking so I didn't think it was dirty.... but if its a lime build up perhaps its sticking against the internal pipe.

Paul48

That noise oscillates slightly. I'd hot-wire the circs and run them without firing the boiler, to eliminate them. My first impression was.....gas valve.

hot_rod

There are a lot of potential noise-makers in a boiler system The mineral build up is usually a slow gradual symptom, not one that just starts from one day to the next.

Other sources could be bearings in the circ, or gas valve regulators. Good troubleshooters just keep eliminating the variables.

If it stops making noise instantly when the burner goes off, then I look at the gas valve.

When the HX is limed up the noise sometimes continues, after the fire goes out, until all the heat is pulled from the copper tube. Not unlike when your tea kettle gets a mineral build up, burner goes off but the percolation continues until the heat energy is gone from the mineral build up. Same with a water heater that is filling with mineral build up.

If the system is leak free, and the water has not been drained and changed, then mineral build up would be less likely, but still an easy fix by circulating a cleaner, which all systems should have at initial start up.

The acid base cleaner is generally only needed when the hx has hard mineral build up. Start up hydronic cleaners are more of a soap based product intended to cut grease, oils, flux, etc , assembly products.

Abracadabra

Paul48 said:

That noise oscillates slightly. I'd hot-wire the circs and run them without firing the boiler, to eliminate them. My first impression was.....gas valve.

+1

I'm leaning towards something in the gas train as well. Did that Laars come with a pump attached to it? If so, then it should have a Auto/Off/On switch to control the pump. Set it to On and it should fire up the attached pump with the boiler off.

llockett

Thanks! No attached pump was with the unit "Mini Therm"...gas valve and burners were replaced with new ones hot rod and that whistle remain...when I shut the unit off, the whistle fades away slowly as the unit shuts down...it sorta winds down, sounds like it fades with the drop of pressure....I can hear the actual pump going off and no whistle in it directly...I can actually hear the sound coming from internal of the boiler near the center left corner of its body...so so so annoying. Here is my youtube link of the issue
https://www.youtube.com/watch?v=3xxMcUglqcE

llockett

This is the order of this annoying whistle...turn therm up to 70, I hear the boiler kick on, I hear the Flu open automatically, I then hear the pump kick in, then the flames come on at the burners, then exactly one minute later the whistle starts at a very low sound as it gets higher and higher to a ongoing hum

hot_rod

Hmmm, if it is a minute or so delay, I'm back to the scaled HX. Gas train noise often starts when the burner ignites and stops instantly when it goes off. Unless it is a step fire or modulating gas valve.

Even cast iron boilers can make strange noises when they scale. I have heard it described as everything from a soft moan, damped boiling, popping, Rice Krispies, even an elk bugle.

If you, or someone has tried or replaced everything else...

If you contact the local Laars rep, boiler scale is usually near the top of their list of noise causing complaints. Low mass, low water content type of HX don't need much of a layer of build up to start talking. Not unlike tankless water heaters.

Of course performance goes down as HXers start to scale up also.

Here is a graph our lab generated showing the effect of scale build up. Same issue in heat emitters as heat exchanger or generators, like boiler HX.

In the UK there are still a lot of open system hydronics, as well as panel rads. Many of the de-scale chemicals you see on the market, Fernox, Sentinel, were developed in and for the open system hydronics in the UK.

Abracadabra

llockett said:

This is the order of this annoying whistle...turn therm up to 70, I hear the boiler kick on, I hear the Flu open automatically, I then hear the pump kick in, then the flames come on at the burners, then exactly one minute later the whistle starts at a very low sound as it gets higher and higher to a ongoing hum

Has the heat exchanger been checked for sooting? Is there sufficient combustion air being provided?

llockett

Thanks hot rod, Abracadabra no it has not, I actually took the cover off the boiler and looked at the top of the HX and it visually looks good....I was afraid to start the unit while the flu and top housing was removed from the unit...I thought that maybe by doing so, I could narrow down the sound but I didn't start it, afraid to make things worst. As of now, my wife turned therm down to 62 so that it don't cycle much within the night but I admit, its cold in here and our kids are looking at me as if I know what too do. so so so lost here and the whistle at night is louder than day cause its quieter. I am wondering if I should add a cleaning solvent but I don't no where to start or even where it goes...hot rod and nick suggest I get a pro, one of the 7 thats been here already, do you think I can do this soot cleaning myself by removing the units cover and accessing the HX or is there more to it?

nicholas bonham-carter

perhaps speaking to someone higher up in the pecking order of the service company would convince them to send over their best tech would work. have them get laars tech support on the line, as well as reading this post.
this is not a completely unusual, once in a million problem.--NBC

llockett

Thanks so much Nich, however after the 3rd tech I called the service company complaining that no one can seem to find the issue and that I insist on a senior tech to come to my home...well they sent him and he arrived "as a mr. know it all" and said...I have been doing this for years and I promise you its a gas valve, so there we went, we ordered a new valve and BANG, nothing. I then called and requested another senior tech and he too stated that he is unaware so I asked that he call Laars and they asked that he clean the unit with a solvent. None the less, my contract does not cover cleaning and if I have them do it, it will cost $550, I don't want to pay this and then the issue remain. I will like to take a chang=ce with cleaning the HX but will love to have advise and guidance...Thnx

nicholas bonham-carter

That doesn't seem like a good contract to me!
The only thing which could be predicted is "a need for periodic cleaning"! Did they install the boiler?
I would think everyone should steer clear of this company -who are they?--NBC

llockett

Hi Nich, yeah well I figured if I have a contract it should be honored to completion of a job and not ti be told, we don't know your issue....I think I will call them today with a threat and perhaps they will come up with something...unbelievable....8 techs in total, at one point there were 5 guys here at once for over an hour.The unit is a small mini therm and not so big....although this is not my career field, I would figure 8 "supposed" professions would have known the issue. I had it installed brand new form a local plumber whom has moved on since....it worked perfect for the 2 seasons and actually still gets nice and hot as needed but this crazy noise is new....last night my wife and I went to a Hotel again...its so loud and annoying, NJ Natural Gas Company

hot_rod

You might want to try Laars again. At their website they list Laars trained service centers. Joanie from Laars hangs around here from time to time, maybe she can help out.

llockett

Thnx HR I will seek out Joanie

llockett

Well finally had someone come look at this unit and they state that its a bad HX, they did not take the boilers jacket off however they "I guess" figures its the HX. The part is under warranty but the guy wants $2,500 to install...is that a lot? do you think that I should continue having someone troubleshoot to see if its another possibility thats causing this tea kettle whistle?

nicholas bonham-carter

have you spoken to Laars yet. 3 years is a short time to have damaged the HX. surely there is a warranty, longer than that. this doesn't pass the smell test.--NBC

Paul48

There is NBC....Parts, no labor, no shipping

Paul48

I'd put something like a Munchkin Contender in, before I'd pay to have that POS fixed.

llockett

I tried reaching Laars but they refuse to talk and support a residential client...they forwarded me to a local service provider...however I had NJR services at my home 8 times and they have yet to have found the issue...unit still whistle like a tea pot

icesailor

For that kind of money, and the length of time it lasted, I'd be seriously considering another brand of boiler. One that last longer than 3 years.

I personally would be getting out my OCD hat to know why it whistled. What makes it whistle. Does the vent pucker when it does it? Does it sing a tune? What tune? The Whistling Gypsy Rover?

RobG

I agree with Ice, I would figure out why it's whistling. Three years is way to short a life for any boiler (unless it was a HydroTherm Pulse) . I would try cleaning the heat exchanger as has been recommended earlier. If that fixes it you then need to figure out why it's scaling up.

llockett

Thanks guys, I will like to see where the sound is coming from but don't know where to start first...can I take the jacket off and run it bare in attempt to narrow it down? an I clean the HX with solvent, where do I insert it? Thanks