Flushing a boiler?

[siderman 1,137]

My hot water bsbrd boiler is hurting. Only 19 yrs old but it bangs & pops (aka kettling) like crazy during the heating season and I've procrastinated giving it attention too long.The likely cause of course is mineral scale build up inside the cast iron exchanger. I've altered the temp range over last season but doesnt change the kettling. Am wondering how effective a flush (power?)of some sort via chemicals or whatever if put thru would be. Anyone have success getting it done- or know someone who does it in Brgn area- or is my exchanger toast....also looked into replacing the exchanger but not really cost effective vs a new unit, which may be in play too.

[maintenanceguy 510]

What brand and model boiler.  Different boilers have different types of heat exchangers.  It's easier to flush the sediment out of some than others.  An acid flush can clear some of the scale but not all heat exchangers can handle the acid.

[siderman 1,137]

its a Crown ABF70 with a 3 section cast exchanger. Been very good to me not one issue ever except this but its the waters fault. I'd like to give an acid flush a shot to see if its worth it just dont know enough or anyone who did/does it.

[T Bill 649]

Sure your noise is not related to air trapped in the system?  Check your air vents to see if they are working. Have replacements on hand cause if they are scaled up and not working they will not reset just leak.  Do not go cheap either, good air vents are worth every penny.  Tasco 400-4 is one model. One on top of boiler, and at least one on top of flow air scoop.  Might find them on each zone.  

[maintenanceguy 510]

Not familiar with that boiler but it sounds like a cast iron sectional.  There are scale control/removal chemicals available from places like Johnstone Supply, United Refrigeration, or your local plumbing supplier.

 

I was a maintenance supervisor for several large commercial facilities for 20+ years.  I'm not a boiler guy but have spent a lot of time working on boilers of all sizes.   

If this was my boiler, I would:

1) replace all automatic air vents and see if that helps.

2) open the feed water bypass (so you get more feedwater flow) and open up the boiler drain at the bottom of the boiler and let it flow for a while.  Just blowing down the boiler can get out quite a bit of junk.

3) use one of the commercial de-scalers in gallon jugs.  Follow directions on bottle. After a few days, try blowing down the boiler again and see what comes out.

4) As a last resort, there are acid flushes.  They are just HCL or H2SO4.  You add the recommended amount, based on the volume of your boiler and let it sit for the recommended amount of time.  You want to keep this in the boiler.  The heavy cast iron sections can handle acid better than your piping and baseboard heat.   After the recommended time, flush and see what comes out.  I've only had this done a couple of times on boilers and plate type heat exchangers.   The results were always less than spectacular.

[siderman 1,137]

OK, thanx, will work on vents and a quicky blow.

[mipafox 438]

OK, thanx, will work on vents and a quicky blow.

I always love a quicky blow.

[ChrisJM981 924]

Ask Deerslayer. That's what he does for a living.

[siderman 1,137]

I looked at the vent, only one Maid O Mist on top of the boiler no scoops or in-line bleeders,  not leaky or corroded. I took the cap off, nothing happened then pressed on the needle and water gurgled out and wouldnt stop untill I put the cap back on, prob not a good thing. Still convinced the boiler is crapped on the inside but you always start cheap & easy first. Anyway will prob need to wait till it gets cool outside to run the 4 zone heat for any testing. The indirct hot water tank has its own zone but its so small not going to make a difference.

ETA: if there was air in the boiler/system wouldnt there have been some trapped at the vent to come out instead of just water?

 

Ask Deerslayer. That's what he does for a living.

He can chime in , not going to impose on him. besides I'm in Brgn cnty and he thinks we all have the kooties here lol.

 

I always love a quicky blow.

was wondering who the first responder to that would be.....

[DeerSlayer 241]

My hot water bsbrd boiler is hurting. Only 19 yrs old but it bangs & pops (aka kettling) like crazy during the heating season and I've procrastinated giving it attention too long.The likely cause of course is mineral scale build up inside the cast iron exchanger. I've altered the temp range over last season but doesnt change the kettling. Am wondering how effective a flush (power?)of some sort via chemicals or whatever if put thru would be. Anyone have success getting it done- or know someone who does it in Brgn area- or is my exchanger toast....also looked into replacing the exchanger but not really cost effective vs a new unit, which may be in play too.

"Only 19 years old" for a boiler is like saying "my car only has 250k miles on it. 25 years is about max life for a boiler. Definitely not working replacing the cast iron heat exchanger. You just replace the entire boiler. If you want it flushed out you call a coil cleaning company to do that.

 

BTW I was just in Bergen county working on my father's 2 family house in Maywood. Both boilers needed service. Now i need a cootie shot lol...

[DeerSlayer 241]

Sure your noise is not related to air trapped in the system? Check your air vents to see if they are working. Have replacements on hand cause if they are scaled up and not working they will not reset just leak. Do not go cheap either, good air vents are worth every penny. Tasco 400-4 is one model. One on top of boiler, and at least one on top of flow air scoop. Might find them on each zone.

Remove all those junk air vents, and the taco air scoop and install a microbubble air scrubber. Like a Spiro vent. Problem solved forever with air.

[Old School 611]

Not familiar with that boiler but it sounds like a cast iron sectional.  There are scale control/removal chemicals available from places like Johnstone Supply, United Refrigeration, or your local plumbing supplier.

 

I was a maintenance supervisor for several large commercial facilities for 20+ years.  I'm not a boiler guy but have spent a lot of time working on boilers of all sizes.   

If this was my boiler, I would:

1) replace all automatic air vents and see if that helps.

2) open the feed water bypass (so you get more feedwater flow) and open up the boiler drain at the bottom of the boiler and let it flow for a while.  Just blowing down the boiler can get out quite a bit of junk. Good idea!  May want to pull the drain valve and have a coat hanger ready to probe the hole if it gets clogged

3) use one of the commercial de-scGoodalers in gallon jugs.  Follow directions on bottle. After a few days, try blowing down the boiler again and see what comes out.

4) As a last resort, there are acid flushes.  They are just HCL or H2SO4.  You add the recommended amount, based on the volume of your boiler and let it sit for the recommended for an hour in amount of time.  You want to keep this in the boiler.  The heavy cast iron sections can handle acid better than your piping and baseboard heat.   After the recommended time, flush and see what comes out.  I've only had this done a couple of times on boilers and plate type heat exchangers.   The results were always less than spectacular.

The other thing you can do is after you get all the loose scale out from a flush, circulate a de-scaler using a sump pump and hose in and back to the bucket..Circulate for an hour in each direction then flush.

[DeerSlayer 241]

The other thing you can do is after you get all the loose scale out from a flush, circulate a de-scaler using a sump pump and hose in and back to the bucket..Circulate for an hour in each direction then flush.

That's basically what a coil cleaning company will do. Saves you from buying a pump, acid, and having to get rid of it. Totally worth the money. A good pony pump is $250. You can buy something cheaper, but it won't last. I use Franks Coil Cleaning in Dover Morris County. They will definitely scale the boiler for less than what it costs to buy everything.

 

 

When they're done, you add a treatment so it doesn't happen again. Just have to be sure the back flow prevention device is working.

[Old School 611]

Little Giant sump pump $50 ebay

Ridlyme  $30 gal (may need 2)

Hoses free

5gal bucket free

 

ridlymemarine.com

biodegradeable

[DeerSlayer 241]

Little Giant sump pump $50 ebay

Ridlyme $30 gal (may need 2)

Hoses free

5gal bucket free

 

ridlymemarine.com

biodegradeable

It's a crown boiler, they have rubber gaskets between the section nipples. Unlike other boilers with steel push nipples. How does that stuff react with rubber?

 

 

Probably going to need a garbage can. A sump pump discharge is pretty violent, and may make a mess pumping it back into the 5gal bucket with the pump in it.

[djg0770 481]

When they're done, you add a treatment so it doesn't happen again. Just have to be sure the back flow prevention device is working.

 

Solid advice.  Also make sure that you have no leaks (some systems have piping buried in concrete...) cause constantly adding fresh water will also contribute to excess scaling.

 

The boiler flush company will be able to tell you whether their chemicals are compatible.

[djg0770 481]

Oh - here's an Installation Instruction sheet if you didn't have it:

 

http://www.velocityboilerworks.com/documents/Aruba-ABF-SPD-ABF-EID.pdf

[Old School 611]

Go to the site. I've used it every 4 years on the exchangers on the boat and they have neoprene gaskets. No problem

 

 

Sent from my iPhone using Tapatalk

[DeerSlayer 241]

Solid advice. Also make sure that you have no leaks (some systems have piping buried in concrete...) cause constantly adding fresh water will also contribute to excess scaling.

 

The boiler flush company will be able to tell you whether their chemicals are compatible.

Easy way to figure that out. Close the supply valve, and watch the Guage for the pressure drop. If there is sub slab piping.

[DeerSlayer 241]

Not having a water softner is the leading cause of scaling lol... may want to think about investing in a softner as well.

[DeerSlayer 241]

Go to the site. I've used it every 4 years on the exchangers on the boat and they have neoprene gaskets. No problem

 

 

Sent from my iPhone using Tapatalk

This is what most guys in the business use. Comes as a complete kit.

 

http://www.flow-aide.com/

 

 

Same basic idea as yours, except the pump moves the solution through much slower than a sump pump will.

[DeerSlayer 241]

Oh - here's an Installation Instruction sheet if you didn't have it:

 

http://www.velocityboilerworks.com/documents/Aruba-ABF-SPD-ABF-EID.pdf

I used to install crown. Now everything gas is wall hung usually these days. Stainless heat exchangers high efficiency. I still do a ton of oil fired cast iron boilers though. But I usually sell Burnham. Had too many warranty issues with crown. They make a few wall hung units now as well.

[DeerSlayer 241]

And for the record I have nothing against you guys in Bergen county personally. I just can't work there, and profit because I waste 4 hours a day driving there, and back. 2 hours down 80 east in the morning, then 2 hours back in the afternoon. It's only 30 miles from my house. But the traffic going each way is insane. I can't handle sitting in that.

[siderman 1,137]

swapped out the vent, drained about a qt and it actually was pretty clean except for the first couple oz's. The safety discharge tho was black and mucky till that blew clear when I wanted to clear out a little pressure for the vent.  I may try a "coil cleaning co" never heard of that. If the price is right may buy a few more yrs but honestly i think its time for a new unit, dont want to start the money pit hole going. My Crown boiler, not one issue ever but for this scaling  and thats not a boilers fault. Might be time to get some quotes before the busy heating system. 

[Brownie^HP 6]

Siderman, have you checked your expansion tank? 

[siderman 1,137]

Siderman, have you checked your expansion tank? 

yes, has a nice hollow ping to it and doesnt feel heavy and sloshy.

As to the flow-aide device, dont see how i can isolate the boiler exchanger into its own dedicated loop like on the hot water heaters w/o having to run thru an entire zone of baseboard. By then its all guess work on how much solution to use as they want at least 50/50 mix and thats a lot and then flushing and purging...meh. If I can get a hold of a coil cleaner maybe they'll know the trick.

[Brisco 130]

Siderman,

 

I'm in the business also. 95% of the noise issues I come across- are air related. I would give the system a good purge first, as long as your near boiler piping is correct. Next, I would do as Deerslayer suggested, and add a micro-bubble removal device (Spiro-vent, Honeywell PV, B&G). Remove the can vent.

 

Check your piping- Is the pump pumping away from the expansion tank/fill valve? You can find a ton of useful info on heatinghelp.com regarding near boiler piping. 

 

Your heating system is a closed system, it shouldn't be getting fresh water so it shouldn't see scale build up like a water heater.

 

If you could, take a video of the noise and post it. Deerslayer or myself could probably tell right away from the noise if it is scale or air.

 

Shane

[Handyman 5,682]

I always love a quicky blow.

 

 

Ask Deerslayer. That's what he does for a living.

 

 

Isn't that illegal in New Jersey?

[djg0770 481]

Easy way to figure that out. Close the supply valve, and watch the Guage for the pressure drop. If there is sub slab piping.

Yup... If the gauge is there and if it works.

[DeerSlayer 241]

Siderman,

 

I'm in the business also. 95% of the noise issues I come across- are air related. I would give the system a good purge first, as long as your near boiler piping is correct. Next, I would do as Deerslayer suggested, and add a micro-bubble removal device (Spiro-vent, Honeywell PV, B&G). Remove the can vent.

 

Check your piping- Is the pump pumping away from the expansion tank/fill valve? You can find a ton of useful info on heatinghelp.com regarding near boiler piping.

 

Your heating system is a closed system, it shouldn't be getting fresh water so it shouldn't see scale build up like a water heater.

 

If you could, take a video of the noise and post it. Deerslayer or myself could probably tell right away from the noise if it is scale or air.

 

Shane

Dan Holohan pumping away, is my favorite book. Heating help is one of my favorite sites too. I answer a lot of stuff on the wall there. Been to a few Dead men seminars too.