HVAC boilers leak after amateur repair attempts
13 posts across 2 communities in the last 60 days; 54% from r/Plumbing.
“Just looking for some advice on an issue we’re having with our heating. We have a conventional boiler system with a hot water cylinder and a cold water storage tank in the loft. Around November last year, we noticed that the radiators would come on whenever the hot water was…”
“I’ve been working on my hydronic boiler after repairing several leaking connections. The good news is that everything is now sealed and I’m no longer seeing any leaks. However, I’m having a circulation/overheating issue that I could use some help diagnosing. I’ve purged the…”
“I need some advice on what could be causing this issue please. A few weeks ago I had a gas safe guy come and reroute my boiler flue (moving it higher to clear extension roof). Same boiler, just a new flue. Anyway, shortly after the new flue was fitted we had a solid day of rain…”
Homeowners are experiencing boiler failures and leaks following DIY repairs, specifically involving the removal or replacement of coils. This results in costly replacements and unexpected breakdowns.
SOURCES (18)
“Just looking for some advice on an issue we’re having with our heating. We have a conventional boiler system with a hot water cylinder and a cold water storage tank in the loft. Around November last year, we noticed that the radiators would come on…”
“I’ve been looking to fix a leak right at the joint visible in pictures and I can’t remove this am I just not twisting hard enough or is there a bolt I’m missing anything submitted by /u/Leather-Account8560 [link] [comments]”
“I’ve been working on my hydronic boiler after repairing several leaking connections. The good news is that everything is now sealed and I’m no longer seeing any leaks. However, I’m having a circulation/overheating issue that I could use some help diagnosing. I’ve purged the system multiple times, but it still sounds like there may be air trapped somewhere in the system. When the boiler fires, I’m getting fairly significant banging/popping that sounds like kettling. I have two circulator pumps, a”
“Hi Everyone, I have a 13 year well mclain combi boiler. This morning after using some hot water I heard rumbling downstairs and the boiler was leaking with a fair amount of steam in the room. I turned off the emergency switch and contacted our HVAC company who services it annually. We tried to restart the unit but it just stays in standby and won't fire (all lights blinking). They diagnosed as bad relief valve and bad aquastat. I am not sure which caused which. My main question/concern is co”
“Purchased an old home with a 14 yr old Burnham oil boiler RSAH135TH-TB that was converted to gas. With all the damage pictured, how far would you take replacing what’s damaged? Include the coil? Is it worth the trouble? Switching to central air would be a plan over the next 5 years if maintenance can help this to the finish line. From my understanding the unit is no longer in production. Thank you submitted by /u/No_Voice_2149 [link] [comments]”
“Any techs familiar with New Yorker PVCG boilers? PVCG40PI-2 (Propane) Replacing my draft inducer, and one of the four mounting studs broke off the flue collector. It appears to be tack-welded from behind, with no access to the back side. Is there a safe way to repair the stud without removing the entire collector? The original resealing kit is discontinued, but it looks like its just cerafelt and RTV? Looks like this is something thats normally removed to clean these things. What can I use to se”
“I stupidly knocked a section of my baseboard heating pipe while doing a renovation, and created a pinhole leak in a 1/2” copper pipe. Very small leak (a drop every 10 sec or so) and it’s relatively low pressure since it’s a part of my baseboard heating system - maybe 20-25 PSI max when it's running. I found a Rothenberger repair clamp at HD which is super tight on the pipe and has a rubber gasket on the inside. This was back in January of 2026. The clamp lasted through three months of the he”
“I need some advice on what could be causing this issue please. A few weeks ago I had a gas safe guy come and reroute my boiler flue (moving it higher to clear extension roof). Same boiler, just a new flue. Anyway, shortly after the new flue was fitted we had a solid day of rain, after which I noticed the boiler wasn't firing. I was going to look more into it but a few hours later (for seemingly no reason) the boiler just started working again. However today we had another few hours of rain a”
“Hi everyone, looking for some input. Houston, flat roof, gas furnace in an interior closet with B-vent going straight up through the roof. Found a droplet hanging off the seam of the 90° elbow inside the closet, with white mineral staining streaking down it, so it's been going on a while. Also water pooled on top of the furnace. Ruled out combustion condensate (furnace hasn't run since spring) and a clogged condensate drain (poured bleach a month ago, heard it run all the way to the sink”
“Live in apartment with communal boiler so we have heat exchangers in each flat. Found mine randomly leaking today and look in to see it’s got a slow leak along with corrosion on a component. Anyone have any idea what this is, what I can do and is it something I could fix myself? submitted by /u/Wilksy20 [link] [comments]”
“Yesterday our hot water turned brown, started sputtering and I found the heater like this. Leaking from the seams everywhere. I'm assuming it's dead. I'm trying to figure out the cause, and if it's going to be covered under warranty, as it is only 2-3 years old. I drained it, and no sediment other an a little rusty water. I haven't been able to get the top off to check the anode rode - the perimeter ring won't budge in the back. Any suggestions for how to approach this? &”
Came home to water in floor. Caught this early. Leaking from hairline crack in this nut. What is this valve name/used for in our laundry? Should I be able to just unscrew…
“Well I did something stupid. Have an oil hot water heater system with boiler for hot water. Hoping to save some oil during the summer we decided to shut off the furnace and only have it on when we need hot water or heat. Well now it leaks when it is off but not on. So I assume the boiler cracked. But have no idea why it only leaks when shut down. Hopefully we could have only that part replaced? submitted by /u/Individual-Ball-9862 [link] [comments]”
“Can anyone see what might be the cause and solution? submitted by /u/apples-and-apples [link] [comments]”
“I noticed my furnace had a bunch of water under it yesterday and after checking the pump worked and the condenser coil tube and fitting were clear, I took off the service panel and saw all this rust. I assume the drip pan is rusted through and causing my leak. I got a new heat pump installed in Jan of 2024 and they supposedly installed a new coil but this looks really bad. They are charging me 200 dollars to come out and look at it and depending on what needs to be done it might cost more. I'”
“I have a new kitchen being installed and they had to lift the 15L boiler a bit (it used to be in the ground), that caused the cold water pipe to be a little bend, can that cause future problems or is it “okay”? submitted by /u/sexMeisterxx [link] [comments]”
“Pressure relief valve. Something has failed either on a boiler or water heater and the safety valve is dumping to prevent explosion”
“Long story short I dropped a bolt into the water jacket of my boiler and have no clue how to get it out. The hot water coil on my slant fin liberty 2 boiler had rusted to the point of leaking. I installed an electric water heater years ago and haven’t used the boiler for hot water so I figured I’d just rip out the coil and replace it with a blank plate. Got 5 of the 6 bolts out no problem but snapped one. Had to drill and tap new threads, while I was waiting for a drill bit to arrive I put the b”