Boiler making loud noise when filling storage tank

caboone

I just recently converted from oil to gas, which appears to be a great move for the efficiency and savings that comes with it. However, I have big problem that is bothering me?



- The boiler (Munchkin Contender) works great when it is heating the house, however, it makes a loud noise (sounds like thunder) when it is filling up the storage tank.



The plumber that installed the system has come by twice, but was unable to fix the issue and has stopped taking my calls.



Before pursing any legal means, I want to get an expert advice on what this problem is and what I should do next. The problem started happening only a fews days after the system went online.



Thank you for your help.

meplumber

Storage Tank?

I assume you are refering to the indirect Domestic Water Heater tank.  There are a few things that could be causing this and most of them are water flow related.  Can you take some pictures of your boiler and the associated piping and post them here.  Then we could try and assist you.

icesailor

Noises:

A "Munchkin" is a discontinued HTP Mod/Con Boiler. A "Contender" is a HTP indirect storage tank. The tank gets filled once with water. After that, cold water flows in and hot water flows out. There is no "Filling". If it is banging and pounding, it is usually piped wrong. There are explicit instructions and diagrams on how to pipe Munchkins. If you don't pipe it as per manufacturers instructions, it will misbehave.

You need to post pictures of the boiler, piping, and circulator locations.

If it is a Munchkin, it should have a 925 or 926 controller. What is the temperature on the controller when the pounding starts? Turn it down to 150 and see if it stops. If it does, the flow through the boiler to the coil in the Indirect is too low. 

gennady

noise

what circulator is installed for indirect tank?

what size piping installed for indirect tank?

on what side of hydro separator indirect is piped?

caboone

pictures

Here are some pictures

caboone

Munchkin Contender

Well, as seen in the picture above, the boiler is labeled "Munchkin Contender" and in the indirect water heater I use is a Top Performer Plus from Vaughn

caboone

Piping

I wish I could provide those info to you. The only thing I know is that I use 3 circulators from TACO. The one for heating the house is a multispeed. There 2 more and one of them push the water into the Inderect Water Heater. Check those pictures above and if you need another picture of a specific section I will take it..

gennady

pumps

could you provide pumps numbers (like 007 or 011) and speed they set to?

gennady

piping

Also, on last picture i see probably piping to the indirect heater (left pump) before twin tee connection, but i do not see 2nd connection there. do you have picture showing indirect piping in more details?

caboone

here u go

Hope this is what u need. if not I will post more. cold water comes from the back of the of the board to the indirect water heater weep. hot water from the boiler to the indirect water goes to the front and it's pushed by a taco circulator

gennady

taco 010

.taco 010 has 10' WC head available .



http://www.taco-hvac.com/products.html?view=ProdDetail&Product=6¤t_category=52

your storage tank has 7' WC head.

http://www.vaughncorp.com/pdf/TPPlusBrochure.pdf



your boiler ( i found it to be low end BTW) does not publish head data for heat exchanger, But for gianoni heat exchanger it is somewhere in 20+ feet of WC. Add to this some piping and fitting, and i think you have to move to next big pump. you have probably lack of water flow, and water starts to boil in the boiler, and because this boiler does not have advanced protection features, you might damage this boiler. I might be wrong, but this is my opinion.

furnacefigher15

First step

Have the installing contractor come back out. Most guys will have no problem coming back out to make system adjustments.



Do you have adequate hot water in the shower?



Could be a pump mismatch, improper boiler or pump setting, or as simple as air still in the piping. Likely a flow problem.

icesailor

Piping:

I think it is piped wrong. The primary pump to the closely spaced tees is OK but what is that other pipe coming off the bottom of the boiler with the circulator on it?

If that pump goes to the Indirect, and not through the secondary piping/closely spaced tees, you might not have enough flow. I personally think that both pumps should run together whenever there is a call for domestic hot water and the primary pump should run with the system pump. IMO, the boiler pump should always be running when there is any kind of boiler call.

A low loss header would have been a wonderful thing.

Paul48

In

your photos you show two circulators. One for the DHW, on the left, and one for the boiler on the right. The next time it makes that noise when the boiler is in DHW mode, try closing the valve directly below the circulator on the right and see if the noise stops. Don't leave the valve closed, open it again, then let us know.

caboone

Hot water

Yes. I do have enough hot water. Most of the times this issue happens when we are in the shower. However, I've noticed that happening during the night when the boiler is adding hot water the IWH.

caboone

Valve

I will run this test and post back.

Paul48

clarity

It's just circulating hot water through a coil in your indirect water heater. The water you use for showering and domestic use never mix with boiler water. The coil serves as a heating element.

caboone

Confused

Yeah.. I am a little confused about this. According to the installer, the TopperformerPlus is like a storage tank. The boiler heats up the water and stores it in the TopPerformerPlus. As a matter of fact, the pipe that goes into this tank connects directly to the the boiler and home heating piping. So, yes, I do believe the water that goes into this tank is the same that I heat up my house with. At least this is how it was explained to me...

Paul48

Yes

It is the same water that you heat the house with, being pumped through a coil of pipe in the tank, with the water you use,being heated by that. If it's easier, visualize a tank within a tank. If you fill the inner tank with hot water, it will heat the water outside of it.In this case, instead of a tank they use a coil of pipe with many twists in it to increase the surface area that the water is exposed to. Does that make sense?

Charlie from wmass

Could be out of adjustment

Has a combustion analyzer been used? The boiler is on high fire when heating the indirect tank. If you can post an audio of the noise that would help.

Mark Eatherton

Chris...

IF, there are check valves on the boiler pump AND the DHW pump, it is piped like the manufacturer wants to see. I'd say the DHW dedicated pump does appear to be somewhat undersized, and if there is NOT a check valve on the boiler pump, then it will rumble when firing on high to satisfy the call for DHW. When properly done, it works as designed. When improperly installed, or missing a check valve, or having a failed integral check, it won't work worth a darn.



And as the photo says, it is a Munchkin CONTENDER boiler, formerly known as the MC, not their DHW storage tank of the same name. If I am not mistaken, this is the boiler that has a carbon fiber water way (except for the combustion chamber) and is the same unit I have in my home in Denver. I have mine set up per the manufacturers instructions and I

ve never had any issues (other than plugged condensate drain from slime) with the system. And to Gennady, it has the intelligence to determine when there is a no flow condition, and will shut the burner down if it see such a condition. But in a situation where there is partial flow, it's not enough of a delta T to shut it down.



EDIT: Upon further photographic review, the DHW pump is NOT piped correctly. Both pumps (DHW and Boiler) should be pumping into the boiler inlet, and both MUST have a functional check valve either integral to the pump or on its discharge. Tell your installer that he needs to come back and install it per the manufacturers instructions, because if you do choose to go the legal route, he WILL lose. It's cheaper to fix it than it is to expose himself to the possibility of legal actions.



ME

Mark Eatherton

The reason you hear the IDHW firing at night.

Is because it is improperly piped, and during a call for space heat, it is robbing stored energy from the IDHW tank and sending it to the house heating system. It shouldn't fire more than a couple of times at night to recover the IDHW tank losses. The pump that is dedicated to doing the DHW is allowing partial flow through the tank due to improper piping and the lack of a check valve in that circuit.



ME

Paul48

Mark

I thought I saw something wrong that could create a suction at the check of pump#1, that's why I suggested that test. But, it is per manufacturers spec., according to the I&O.

caboone

Boiler

I dont know much about plumbing. However, I know what is happening is not supposed to. I will try to make a video and place on youtube for you to see.



Unfortunately, I cannot get a hold of the installer. I have called multiple times, and left messages but I cannot get him to come by or call me back. I am at a point where I cannot deal with this for any longer.



He seemed good at first, did a clean job and was responsive before and during installation. Now I can see him...



I will call him a couple more times and if I dont have any responses, I will send him a letter and lawyer up, right after.



Thank you all for the help!

Paul48

Did

you try the test?

caboone

Circulator and Pipe Coming Off the bottom of the boiler

From this picture:



The circulator on the right pushes cold water into the boiler as well as the Indirect WH using a pipe right on the bottom that comes up thru the back of that board and into the Indirect WH. The circulator on the left pulls hot water out of the boiler and into the Indirect WH. There is another Multi-Speed Circulator that is further to the left (Does not show on this picture) that sends the water thru my house for heating and that uses the pipe right on the middle.



What confused me is that how can you have a hot water pipe(water flowing up / pipe in the middle) and cold water pipe (water flowing down/pipe on the right) on the same horizontal piping. Perhaps it is right, but I am confused. But, why do we need to have the horizontal pipe connecting?



Hopefully that is a little clearer now.

caboone

Probable damage to the boiler

I totally agree with you. I have been worried about damage as well. Unfortunately I cant get a hold of the installer. Last time I spoke with him, maybe 3 weeks ago, he said that he need to come by and change the circulator. I havent heard from him since.

caboone

Test

I havent been home much lately and when I am home, the boiler does not make that noise. However, I will make it act the same today again and will perform your suggested test. Thanks,

caboone

Hot water

 I have not problems with hot water.

Mark Eatherton

Paul,

I stand corrected. See this PDF



http://www.htproducts.com/literature/lp-171.pdf



If you go to page 31, and look at figure 12, the DHW extraction pump does NOT pump towards the boiler pump. Regardless, the missing check valve on the boiler pump is the cause of the problem. The water is NOT flowing 100% through the boiler during a call for DHW. It is partially bypassing the boilers heat exchanger, causing it to flash to steam. The onboard controls will eventually catch up with the fire and shut things down.



Based on the boiler pumps appearance, it does not appear to have an integral check valve on it, and I think that this is the main problem. If it had an integral check valve on it, the impeller suction inlet would be MUCH deeper to allow for the installation of the integral check valve. To the original poster, give us a good picture of the nomenclature plate on the left hand DHW pump and the right hand boiler pump to confirm. If it doesn't say IFC after the model number, then it doesn't have an integral check valve, and they MUST both have checks.



Sorry for the confusion. I'm crossing up the I&O manuals from the different boilers I've installed over the years. Here is a link to my preferable way of doing this sort of piping from Lochinvar.



http://lochinvar.com/_linefiles/XL%20Near%20Boiler%20Piping%20Diagram.pdf



You can see where the confusion arises. I can see on the HTP drawing how it would be possible to have bypass even with check valves in the pumps, but I'd have to be standing in front of it, putting hands on the pipes, doing an Ohhh, Ahhh test to be sure.



ME

Paul48

There's

a good picture of the DHW nomenclature, and it is IFC. We need to see one for the boiler pump.If that's the case,it's an easy fix.

Mark Eatherton

Yeah...

Provided he can get the attention of the installer if he's still around... A quick and easy swap out to an IFC would do the trick.



ME

icesailor

Correct Piping:

ME is right.

Just because you don't notice a problem with the DHW, doesn't mean there isn't a problem with the piping. If it was piped correctly, it wouldn't be doing what you describe. If it was piped and wired correctly, it wouldn't be doing what it is doing.

What you describe isn't common and is usually only seen with incorrect piping, wiring or both.

I once heard someone say that water doesn't care where it goes. Maybe yes, maybe no. But it will go where it can if you let it. A good Navigator always knows where he/she is. Same with piping and where the water can go. You need a good Hydronic Navigator to navigate and plot a course of where the water is going, when and how.

JLC

Boiler Noise, damaged, 3rd one, plastic impella thingy.

Munchkin, 140M installed winter 2008, 1 st year plastic impeller disintegrated, replaced impeller and added 24" in of  3 in plastic piping  per the repair MAN.  2009 BOILER WORKED ok no noise, quiet power on, 2010 same issue, had to replace impeller again this time it cost me $290.00, they said out of warranty same as 2008 repair, no noise 1st year, some very minor noise nothing to really get my attention, winter 2010/2011, 2011/2012 some rubbling noise now and again never really heard it when I tried to monitor the boiler, cycling power on and off.  Winter, Oct, Nov and Dec 2012 noise increased monthly now the "roar/rushing shakes the boiler and vibrates up through 2 floors the impeller is destroyed again, brittle and falling apart.  Just started research in last 2 weeks, being a penny wise and pound foolish I've delayed getting repairman in..  Will contact Munchkin tonight/tomorrow and try to buy stainless impeller and see if I can change it out myself.  

caboone

PROBLEM FIXED

Hi,



The reason why my boiler was making that noise, was because the plumber had installed a regular Taco Circulator. He switched it to a Taco 3-Speed Circulator and left it at HIGH. Since then I have had no issues with noise.



Thanks