Question? Just ask us!
Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
InspectAPedia ® Home
AIR CONDITIONING & HEAT PUMP SYSTEMS
BACKDRAFTING HEATING EQUIPMENT
BACKUP HEAT for HEAT PUMPS
BANGING HEATING PIPES RADIATORS
BLOWER FAN OPERATION & TESTING
BOOKSTORE - InspectAPedia
BTU USAGE MONITORS
CARBON MONOXIDE - CO
CIRCULATOR PUMPS & RELAYS
DIAGNOSTIC GUIDES A/C / HEAT PUMP
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DIAGNOSE & FIX HEATING PROBLEMS-FURNACE
DIRECT VENTS / SIDE WALL VENTS
DRAFT REGULATORS, DAMPERS, BOOSTERS
DUCT SYSTEM & DUCT DEFECTS
ELECTRIC HEAT, DIAGNOSIS, REPAIR
ELECTRIC MOTOR DIAGNOSTIC GUIDE
FAN, AIR HANDLER BLOWER UNIT
FLOODED HEATING EQUIPMENT REPAIR
FLUE SIZE SPECIFICATIONS
GAS BURNER Flame & Noise Defects
GAS PIPING, VALVES, CONTROLS
GEOTHERMAL HEATING SYSTEMS
HEAT PUMPS, DIAGNOSIS, REPAIR
HEATING COST SAVINGS METHODS
HEATING OIL PIPING TROUBLES
HEATING OIL TANKS
HEATING SYSTEM NOISES
HEATING SYSTEM TYPES
GAS LP & NATURAL GAS SAFETY HAZARDS
MANUALS & PARTS GUIDES - HVAC
MIXING / ANTI-SCALD VALVES
MOTOR OVERLOAD RESET SWITCH
NOISE, HEATING SYSTEMS
ODORS FROM HEATING SYSTEMS
OIL FILTERS on HEATING EQUIPMENT
OIL FILL PIPE LEAKS
OIL SPILL CLEANUP / PREVENTION
PLASTIC Plexvent / Ultravent RECALL
PUFFBACKS, OIL BURNER
RELIEF VALVE LEAKS
Reset Switch - Heater Primary Control
RESET SWITCH - ELECTRIC MOTOR
Reset Switch - Stack Relays
SAFETY, HEATING INSPECTION
SAFETY RECALLS CHIMNEYS VENTS HEATERS
SOLAR HEATING SYSTEM DESIGNS
SOOT on OIL FIRED HEATING EQUIPMENT
STEAM HEATING SYSTEMS
THERMOSTATS, HEATING / COOLING
VIDEO GUIDES: Heating System Videos
WINTERIZE A BUILDING
WOOD, COAL STOVES & FIREPLACES
WOOD STOVE SAFETY
ZONE VALVES, HEATING
Heating boiler chemicals, treatments, & leak-stop: this article describes various chemical additives & treatments used in hot water & steam heating equipment to condition water, prevent corrosion, adjust pH, and to stop boiler leaks. We list products & product sources, describe boiler chemical properties, and include links to the products' MSDS information. We also discuss & link to additional heating equipment troubleshooting information such as how to find and fix leaks.
Green links show where you are. © Copyright 2014 InspectApedia.com, All Rights Reserved.
Reader Question: using Leak-Stop in a Hydronic Heating Boiler: how to fix clogged zone valves & air bleeders
2/4/2014 Ray said: [originally posted at ZONE VALVES, HEATING]
Ray, I took a look at the Hercules Boiler Liquid described as stop-leak for warnings about clogging of zone valves or circulators and didn't see any warning. It is significant that at least some of the products I reviewed, including Hercules Boiler Liquid explicitly assert that they do not clog heating systems. Quoting:
Watch out: nevertheless a quick search for "boiler leak stopper clogging" will indeed disclose some complaints by HVAC techs and others who cite occasional problems with clogged check valves, boiler drains, and other components following boiler stop-leak products. Typically the complaints I found did not name the product used.
Steps in Un-Clogging your Stop-Leak Clogged Boiler [suspected cause]
1. If your zone valves have a manual-open position and latch, use that to move the zone valve open - at least you'll have heat, and moving the valve (rarely) might free it up
2. Try (with the heating system cooled down) opening and cleaning a manual air bleeder if that's what you've got; if you've got only the float type air bleeder devices, indeed the bottom opening or float could be stuck. Those are inexpensive devices; I'd remove an old one, allow a small amount of boiler water (ounces) to blow out the mount opening, and install a new one.
3. Depending on where the boiler leak was, is it possible your system is air bound? If so we can point you to diagnosing and fixing that problem.
4. If removal of a boiler component confirms that it was clogged, I would contact the company for advice. But before calling them, review the product use instructions I quote below - it might save some embarrassment.
Product instructions for the Hercules boiler liquid you used are quoted from the company's information
Boiler Leak-Stop Product Sources
I list Hercules boiler liquid stop leak first because it's the product used by the reader above and because it's widely available at heating suppliers and from other sources. A common ingredient in many of the boiler stop-leak products listed below is sodium silicate. Some products contain additional or alternative chemicals and sealants.
Im a journeyman plumber and I know how to braze but I'm not sure how to go about repairing a pinhole leak in a copper hot water baseboard heater. Obviously it has to be dry before I can braze it but how do I drain it and once repaired how do I properly fill it up with water and bleed the excess air?
Reply: solder repairs of small leaks in copper heating baseboard piping
The proper repair of a pinhole leak in copper piping would be soldering not brazing. But you'll most likely need to remove the water from the baseboard heater first. Or one can cut out a bad section of tubing or piping and solder in a short section with unions and copper piping of the same diameter. Be sure to properly sand and prep the copper pipe surfaces, remove any burs, and use a soldering paste or flux to assure a good solder connection.
Watch out: often the presence of a single pinhole leak is an indicator of more trouble ahead. Corrosion, or too-thin or defective copper piping may be prone to developing multiple leaks. I'd go ahead and patch or repair the present leak, but I'd keep an eye on the building heating distribution piping and baseboards for more leaks down the road.
Josh asked: I have an old one pipe steam radiator that has a small crack about 8 inches up. It drips a bit but my concern is the steam. Is this dangerous to have expelled into the air as far as breathing quality. I am not sure If it is a health issue. I have some concerns about having It replaced with a cheap one from china. Thanks so much for your help. - Josh (also by email) J.F. Thank you so much for your help.
R said: Today at work, a few pipes and radiators blew in some of the rooms. The leak and steam got so bad you could hardly see your hand held out in front of your face. I was in there for a while trying to find the shut off for the water and keeping the water from leaking out into the hall. I was breathing all that steam in for quite some time and I was wondering if there is anything I should be worried about. My lungs and eyes were a little irritated, but I am wondering if there could be something more. - R. 1/30/2014
That said, here are some things to consider:
Follow-up comment: Harmful chemicals in steam from steam boilers?
Thanks for the quick reply Daniel. I was unsure if chemicals were commonly used in the w
Reply to R about steam radiator leaks & chemical exposure:
While residential and most commercial steam systems operate at very low pressure - under 1 psi, there are some commercial systems that work at higher numbers - where an actual explosion would be potentially dangerous.
List of common chemicals found in steam boiler water treatment compounds and reference to their MSDS information
For an explanation of pH and its importance see WELL DISINFECTANT pH ADJUSTMENT
Carbonic acid (H2CO3) formation in heating boilers and the resultant need for boiler water treatment is discussed at HEATING SYSTEMS
Check with your boiler service company and take a look at the boiler service tag - let me know if any additives were used in your system (unlikely in residential steam boilers) and we can research further by reviewing the MSDS for those products.
Corrosive liquids used in some treatment compounds are skin, lung, and eye irritants (and considered unlikely to be ingested), but you would not expect to find these being released at harmful levels into occupied space from a steam radiator steam leak, since the same steam is also vented quite normally through steam radiator vents during normal system operation.
Try JB-Weld Epoxy for Cracked Home Heating Radiator Repairs?
Some readers have reported and we consider that it may be possible to repair a small crack or leak in a cast iron radiator using an epoxy product. One source to consider (we have not tried this) is JB-Weld, a producer of a range of epoxy and sealant products sold most readily in automotive supply stores and some building supply stores. firstname.lastname@example.org.
However if the radiator leak or crack is not in a location at which you can thoroughly clean and prep the surface, we're doubtful about this approach.
For repairing leaks in cisterns see CAULKS, NONTOXIC
Green link shows where you are in this article series.
Frequently Asked Questions (FAQs)
No FAQs have been posted for this page. Try the search box below or CONTACT US by email if you cannot find the answer you need at InspectApedia.
Try the search box just below or if you prefer, post a question or a comment in the Comments box below and we will respond promptly.
Search the InspectApedia website
HTML Comment Box is loading comments...
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.