Boiler Noise at Startup

cbrillante23

Hello all! I am new to this site and am hoping to get some help from all the knowledgable folks here. I recently had my gas-fired steam boiler serviced (flushed, systems check, inhibitor added, etc). My plumber noted that he removed a decent amount of buildup while flushing. I don’t think the previous owners were doing the level of maintenance they should. Since the service, however, the boiler is making quite the loud noise during each cycle start. Sounds like popping/banging - I don’t think I can attach a video here but I will attempt to take an audio file. Once steam starts to be made the noises stop and the boiler is as quiet as it should be. Rads all get hot, are all pitched properly (one-pipe system). Main vent seems to be operating properly too. It’s really just the noises at startup. Had the plumber back. He pulled some more water from the system. A bit of sediment seemed to come out. He asked me to take a bit out for the next week to see if there is any residual sediment. 

Now that all that previous sediment/sludge has been removed, is it possible that there’s a bit still in the system and that’s reacting with the water during start-up? Sorry for the long run-on of a post. I look forward to any insight! Thank you!

ethicalpaul

Here are the questions I have for you:
- Where is the noise? (I would guess it's in the boiler since you said it happens before the steam is being created)
- Is it in fact only noisy before the steam is being generated?
- How much and what kind of "inhibitor" did your tech put in?
- Does your water level change during a heating cycle, and what level is it at during the cycle?
- If you drain off just a little water what color is it?

If you want to make a video that is great. You can upload it to Youtube, and keep it private if you want so that only people with the link can find it then post the link here.

If you do that (and I would urge you to) then after recording the sound, step back and show us the piping around your boiler in the video. Don't move too fast. Get it from floor to ceiling.

EdTheHeaterMan

What Paul said!

cbrillante23

@ethicalpaul @EdTheHeaterManThank you gentlemen for taking the time to respond. 

ethicalpaul said:

Here are the questions I have for you: - Where is the noise? (I would guess it's in the boiler since you said it happens before the steam is being created) - Is it in fact only noisy before the steam is being generated? - How much and what kind of "inhibitor" did your tech put in? - Does your water level change during a heating cycle, and what level is it at during the cycle? - If you drain off just a little water what color is it? If you want to make a video that is great. You can upload it to Youtube, and keep it private if you want so that only people with the link can find it then post the link here. If you do that (and I would urge you to) then after recording the sound, step back and show us the piping around your boiler in the video. Don't move too fast. Get it from floor to ceiling.

Answering your questions first:
1. Correct, the noise is in the boiler, seems to be towards the back a bit more but hard to say for certain.
2. Correct, the noise is only at startup. Once steam begins to be made the noise stops. And the noise does not return at the end of the cycle. 

3. I’m not sure exactly what type and how much. I can get that info though. It has changed the water green if that helps a bit. 

4. I have not noticed any surging or drastic changes in water level during the heating cycle. It seems to stay right around the 3/4 mark where it’s been established since the service. 

5. I recently drained a little to see if any additional sediment would come out and the water is pretty much all yellow/green (you can see in the video the coloring on the sight glass - of course when draining it’s got some brownish tint mixed in)

Here is the link to a YouTube video of the boiler at startup https://youtu.be/O_kKyExbaB0. Please excuse some of the louder noises in the beginning, my dog was doing laps up above. I think you should be able to get a good idea of the sounds and overall piping through this video but please let me know if you need additional views. I appreciate the help!

Chris_L

It is hard to tell for sure from the video, but it sounds like you've got kettling especially if it happens just as or before water starts boiling.

This means you still have sediment in boiler. I'd try carefully blowing down the boiler from both of the drain valves while it is running to get whatever sediment you can out. If that doesn't work I would drain the boiler completely, refill with water and turn it on for a while to produce steam. (Always do this after adding water to eliminate the oxygen in it.)

And if that doesn't work, you might try this: https://www.oatey.com/products/hercules-boiler-heating-system-cleaner--1728813847 I've had good luck with it in eliminating kettling in a couple old boilers.

cbrillante23

@Chris_L Thanks for the feedback. Just a few follow up questions for you:

- what’s the best approach to blowdown from both of the drains?
- if I were to drain it completely, should I have the inhibitor added again? Or just water?
- and regarding the cleaning product, do you have any insight on how best to use it? What is your process? 

I appreciate the help!

ethicalpaul

I agree with Chris_L this is probably kettling probably due to sediment.

The sediment separates water directly adjacent to the bottom of the boiler (where the fire is), so that water gets to boiling temperature while cooler water remains above the sediment. Then the bubbles of steam hit the cooler water and they collapse causing those sounds.

If you have little or no sediment then of course the water circulates within the boiler due to convection and it all warms up pretty much at the same time so there is no/little collapse (like you see in a pot on your stovetop.

That green treatment I have tested and it gave a bad result for me. I would let it live in there for a couple weeks though in hopes that it might break up some sediment, then I would drain the boiler and see if you get any chunks or cloudiness or sludge out of it.

I like to drain immediately after boiling (if I'm going to--but I try never to drain due to the damage caused by fresh water), but you have to be careful not to burn yourself of course.

I'll look to see if I can find my video where I tested that green junk. I use 8-way but I only add enough to get my PH up to 11 (keeping your PH at 10 or 11 will greatly reduce corrosion in the boiler)

ethicalpaul

Oh also I wanted to tell you good job on the video once you moved around that massive green support post LOL. Your boiler is piped nicely, not like most of the nightmares we get here.

Update: I looked back at my videos and I remember now that green stuff is probably Surge-X. I don't have my video up yet for SurgeX but I do remember that it caused surging in my case, which is the opposite of what it's supposed to do.

I don't think you're getting surging based on your video, which is good, so yeah I'd keep that garbage in your boiler for a couple weeks to see if it will break up some of your sediment and then drain it out and then if I were you, I'd try some Rectorseal 8-way. Buy the 16 oz container from Amazon or wherever, and put maybe 1/2 cup in and see what that does.

My old boiler had a lot of sediment from the previous owners and I could never get it all out but 8-way did bust up a lot of it and helped me quite a bit.

Think of this as a process...you aren't going to clean out your boiler in one attempt...you should expect to put in some treatment, run it for a couple weeks, then drain some to see if you can get some gunk/cloudiness out, then repeat.

If you get surging you'll know you maybe used too much treatment, or it worked too well and busted loose a lot of sediment. If that happens just drain off the sediment and try again with a little less treatment (again, I highly recommend 8-way). You'll know it's surging if your water level drops more than an inch or two during your steaming cycle. You are going to learn so much about your boiler!

If you want to see what surging looks like, here is one of my early videos from when I didn't know hardly anything:

https://www.youtube.com/watch?v=WSRvvNQ5WLc

Chris_L

cbrillante23 said:

@Chris_L Thanks for the feedback. Just a few follow up questions for you:

- what’s the best approach to blowdown from both of the drains?
- if I were to drain it completely, should I have the inhibitor added again? Or just water?
- and regarding the cleaning product, do you have any insight on how best to use it? What is your process? 

I appreciate the help!

1. To blowdown, just open each of the valves, one at a time, after the boiler has been running for 10-15 minutes and drain off about 1/2 to 1 gallon. Be careful not to scald yourself. Let the boiler cool and add water to the fill line. Restart the boiler for the same time to get the oxygen out of the water.

2. I don't know what you are using for an inhibitor, but I would refill it with plain water after draining.

3. To add another treatment, you'll need to access the boiler above the water line. If you don't have a plug or valve for this purpose, you may have to remove the pressure relief valve, add the treatment, an put the relief valve back on.

4. For the Hercules boiler treatment, I follow the instructions on the bottle. (Though with some of these products it is better to start with a half-dose or less.) Don't mix treatments in any case.

cbrillante23

@ethicalpaul That support column is in such a great place right?? Lol. Thanks for all the information. This is super helpful. Kettling makes sense based on how much debris was removed during this servicing. So just to recap, I’ll leave the “green” stuff in for another week or so (it’s been in about a week thus far), then drain the system fully? Ideally after it’s finished a cycle, then add the 8-way (or treatment of choosing) and let that run in the system for a few weeks, drain again, rinse, repeat, etc. like you said, this is a process and that makes sense. Especially on a boiler that may not have been serviced as well as it could have been in the past. And just to confirm, should I drain the system fully between treatments? And I guess it would be beneficial to add some water in before adding something like the 8-way. Thanks again!

cbrillante23

@Chris_L Thank you for the responses. This information is also super helpful as I put together an action plan to getting this boiler cleaned up. I appreciate it! Just curious, is it beneficial to hook some sort of hose up to the drains when opening? I’m tight on space as you can see in the video, I can jam a bucket in the fortunately just curious if there was a benefit with a hose. 

ethicalpaul

In a week I would drain the whole thing, then refill to about 1/2 way up the gauge glass (no sense filling it all the way up during this process) and put in your treatment of choice (not SurgeX in my opinion) like Chris_L said.

Then for additional cycles after this, no I wouldn't necessarily drain the whole thing. You have to judge. Normally the most dirt will be in the first couple gallons. If it starts to come out clear (or clear plus the color of the treatment), you can stop and refill and add some more treatment.

If it's coming out solid brown like you see in my video above, then yeah I'd drain all that out.

Eventually you'd like to get to clear with just the tint of the treatment, but again, you don't have to rush it. Fresh water is harmful in that is causes increased corrosion, but the treatment will inhibit that. When you heat the water the first time, it drives out the excess oxygen. The real damage from fresh water is when the system is leaking steam or dripping water somewhere and a gallon per week or even per day throughout a whole heating season occurs.

cbrillante23

@ethicalpaul Appreciate the follow up. Sounds like I’ve got some tinkering to do but I feel like I have a much better understanding of what is happening. I’ll be sure to update along the way. Also, I see you are from Cedar Grove. Good to chat with another North Jerseyan (I’m from Pompton Lakes). Cheers!

ethicalpaul

Nice! There's a lot of steam in NJ for sure