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Boiler still leaks after changing out relief valve, Expansion Tank, Regulator, Air Vent....

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yekasi
yekasi Member Posts: 14
edited January 2 in Gas Heating

Hello. I had a previous post from a year ago that i had leaks coming out from the Relief valve and my boiler reads 30 PSI all the time. I received suggestions on changing out component and i have done that already , however it is still leaking. I am at a point that i am unsure what to change next. Yes i am aware that my old post was more than 12 months old, and life got busy with different things, and i just let it leak into a sump pump … and my sump pump recently failed (I am guessing may be due to water temperature from the leak?) so i want to fix this problem.

Question: How do i continue from here, and what else could be the problem? The PSI is constantly at 30 and i believe thats why the water is leaking. (So it is doing its job)

Old Post Link:

I did have an handy man to help me change out the relief valve and the regulator because the relief valve was in a very awkward position and i am a bigger guy and couldnt fit my elbow/hand into that area. While he was here, i also asked him to change out the relief valve… we did drain the system to replace all these components. The only thing i regreted was i had bought a Taco regulator for him to replace, but he didnt see it, and replaced it with one of "his" usual ones. When i saw it, it was already replaced, so i just left it. It seems to read the same specs.

The boiler is a CG Boiler (CG-5-SPDN Model) and it is a rather complex system (I feel)… It has 4 zones like this,

  • 1st floor
  • 2nd floor
  • Sunroom (Radiant heat)
  • To the Indirect water heater

Things already replaced:

  1. Same exact pressure relief valve from Supply house
  2. Same Expansion tank from Supply house
  3. Same air vent from Supply house
  4. New Regulator from the handy man. (It was a green Taco)

The water leak is like a little water stream now, and it is no longer dripping. It first started as a drip a year ago and now it has developed a small water stream… See picture below.

Here are a new set of Pictures that shows the replacement.

IMG_6070.JPG

IMG_6072.JPG IMG_6071.JPG IMG_6069.JPG

Comments

  • Grallert
    Grallert Member Posts: 1,062

    Right off the top of my head I suspect the coil in the indirect water heater has a hole allowing domestic water pressure at perhaps 60psi to pass into the the boiler side which should be around 12psi. You can test this by closing the cold water to the water heater for some amount of time. You can hasten this by draining a bit of water out of the boiler to lower the pressure to about 12psi and see if it climbs or leave it and see if the dripping stops when the pressure get to a tad below 30.

    Miss Hall's School service mechanic, greenhouse manager, teacher, dog walker and designated driver

    Intplm.HomerJSmithbjohnhykcopp
  • hot_rod
    hot_rod Member Posts: 26,721

    With the fill pressure lowered in the system to 15 psi, turn off the new fill valve. Does pressure increase?

    This would eliminate the valve leaking past.

    Was the expansion tank pre-charge checked before it was installed? does the tank feel heavy if you tap or shake it gently? It may be waterlogged. On rare occasions the diaphrams are stuck in the tank and they do not allow expansion.

    The SuperStor tank could have a tiny leak in the coil, so water pressure from the tank is over-pressurizing the boiler. This would be my bet if everything else is new and checked.

    I see a valve on the pump that supplies the SuperStor, is there a valve on the other side of the tank? You need to isolate both sides of the tank coil to rule this out. How old is the SuperStor?

    Seems like a lot of checks on the system, but I don't see that the expansion tank is checked away from boiler expansion, so that is okay.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    GGross
  • yekasi
    yekasi Member Posts: 14

    The expansion tank was pre-charged, and i have checked the PSI level before installing. I knocked on the tank for the "ping sound" and i can feel the half hollow and half solid which i believe is working correctly.

    the superstor is likely about 15 years old.

    Which valve near the superstor pump are you referring to? I am attaching another photo that shows the indirect water heater.

    Screenshot 2026-01-02 111857.png

    I am also not following this comment. Can you elaborate? —> but I don't see that the expansion tank is checked away from boiler expansion, so that is okay.

    There was an error displaying this embed.
  • hot_rod
    hot_rod Member Posts: 26,721
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    bjohnhy
  • Grallert
    Grallert Member Posts: 1,062

    The red handled valve that's next to the ladder in the picture stops the domestic cold into the tank. If you close that the street pressure will stop feeding into the tank. The over pressure will drop if in fact there is a leak in the coil.

    Miss Hall's School service mechanic, greenhouse manager, teacher, dog walker and designated driver

  • hot_rod
    hot_rod Member Posts: 26,721

    That is another option.

    If you shut off water to the tank and someone opens a hot faucet, dropping the house pressure then boiler water could be pushed into the tank from the 30 psi in the boiler. If there is a coil leak.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • yekasi
    yekasi Member Posts: 14

    I see what you mean now. And no there is no more valve on the other side.. There is only 1 valve to shut off the water going back into boiler (The return). It passes through the green flow check valve and then into the water heater directly.

    i have attached a few more pictures to show the system.

    Q1) Could i just somehow got a bad expansion tank even tho its new? it was prechecked at 12 PSI before i installed it. If i use a tire pressure gauge to measure hte PSI now, i will accidentally let some how, is it safe to pump air back in while the heater is in operation?

    Q2) You said, "With the fill pressure lowered in the system to 15 psi, turn off the new fill valve. Does pressure increase? This would eliminate the valve leaking past." Did you mean to adjust the new handyman regulator (aka the Fill Pressure valve?) to 15 PSI? How do you lower the pressure to 15 PSI to begin with? ANd by turning off the new fill valve, you mean turn off water into this new handy man regulator? (Regulator and fill valve is the same thing, right?)

    IMG_6084.JPG

    IMG_6085.JPG

    IMG_6086.JPG

    IMG_6087.JPG
  • hot_rod
    hot_rod Member Posts: 26,721

    1 yes on rare occasions the diaphragm in the tank is stuck to the connection nipple and will not allow expansion in.

    But at 30 psi you should feel water in the tank, shake or tap to see if it has fluid in it. It should also warm up if fluid is being expanded into it

    2 you need to get the pressure in the boiler below 30 psi to track down where and why it is getting to that pressure

    My thought is the indirect, if in fact you have checked the other possibilities

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Grallert
  • yekasi
    yekasi Member Posts: 14

    I just did a test following steps to test..


    1) I hand feel the pipe where water feeds into the regulator, i can feel water flowing inside... 

    2) turn off water supply into regulator and turn off boiler.

    3) release some water through the hot water heater valve.  (See picture of the green hose).

    4) I was only able to get the pressure to about 15 PSI after bleeding some water out from that hot water valve for the return water.. 

    5) the leak stopped and temperature slowly dropped to 140. (was 150-160 to begin with)

    6) I hand feel the pipe into regulator and this time no more water movement.

    7) I turn on the water into the regulator and i still do not feel water movement.  Pressure remains at 15 PSI and no water leaks.

    8) Turn on boiler, and boiler fired up right away... and i can feel water movement inside the pipe going into regulator and out of retulator.

    9) pressure reached 30 again, and leaking starts again.


    I did not adjust regulator, as i need to research into how to.  i believe this is the one i have from the handyman.


    http://hydromastersupply.com/product/show_product.php?id=1080

    IMG_6099.JPG IMG_6098.JPG

    IMG_6094.JPG
  • Steamhead
    Steamhead Member Posts: 18,248

    @yekasi , you need to call a pro. Where are you located? We might know someone……………

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • yekasi
    yekasi Member Posts: 14
    edited January 3

    I am in New York, Long Island, Nassau County near LIE Exit 37. I would like to get someone who knows how to diagnose this and fix this problem.

    Please recommend someone if you can. Thanks.

  • Jamie Hall
    Jamie Hall Member Posts: 26,884

    There are several folks who work in Long Island. Click on the "Find a contractor" tab.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • pecmsg
    pecmsg Member Posts: 6,814

    This is a long island. Can you narrow it down a little bit?

  • yekasi
    yekasi Member Posts: 14

    Long island Nassau county. 495 highway near exit 37.

  • pecmsg
    pecmsg Member Posts: 6,814

    That narrows it down. TY

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 11,636
    edited January 3

    Exit 37 ?!?! LOL… That sounds like a New Jersey resident. All of us in NJ live near an exit from some highway. I was exit 17 on the Parkway. When I lived in Philadelphia I lived in a parish. Holy Child and then Incarnation. Even my Jewish friends knew what parish they lived in. LOL.

    You can click "off topic" below

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    Larry WeingartenJamie Hall
  • HomerJSmith
    HomerJSmith Member Posts: 2,722
    edited January 5

    The pressure regulating valve is a Hydro Master 0571300 valve. A Watts knock off, I suppose, so, you can use the Watts instructions to adjust it. If the boiler is cold and the boiler gauge reads 15 PSI after bleeding it down, it's set correctly.

    There are only three ways pressure can build up in your sys. The Hydro Master fill valve is leaking. The water in the boiler heats up and expands and the increased water has no where to go. The heat exchanger in the indirect tank is has a hole in it allowing street water pressure into the boiler sys as @Grallert and @hot_rod stated.

    You won't see street pressure in the boiler sys as the maximum pressure is set at the boiler pressure relief valve, 30 PSI. Follow @hot_rod's advice and shut off the cold water feed to the indirect heater.

    As a further note, the Ex tank is positioned wrong. It is upside down and installed in the wrong location. It should be installed on the return line to the boiler before the pumps. A cast iron boiler has very low pressure loss thru the HX, so you are essentially pumping into the Ex tank instead of away from it.

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 11,636
    edited January 3

    @HomerJSmith said: As a further note, the Ex tank is positioned wrong. It is upside down and installed in the wrong location. It should be installed on the return line to the boiler before the pumps. A cast iron boiler has very low pressure loss thru the HX, so you are essentially pumping into the Ex tank instead of away from it.

    How do you install an expansion tank before all of the pumps? You can install it before one of the pumps …but you can't install it before all of the pumps unless you go all the back to the boiler where all the zones branch off from the boiler's supply …and that is only a short distance from the current location.

    Unless you have come up with something I have never seen before!

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • HomerJSmith
    HomerJSmith Member Posts: 2,722
    edited January 3

    @EdTheHeaterMan, It was only the boiler pump that I meant (but we have 3 boiler pumps). I like pumping into the greatest pressure loss. I not sure what all the pumps do except the 2 boiler and indirect pump. I would have pumped into the indirect tank instead of away from the tank. The two rear pumps on the boiler return are on heating circuits, baseboard? I assume that the pump on the thermostatic mixing valve is going to a radiant circuit.

    So, Ed, you have a valid point. When you have 3 boiler pumps which do you connect the X tank to? I would say to one of the rear pumps that runs the most and is the longest circuit, greatest pressure loss.

    The system isn't piped correctly, but what is, is. When I zone with circulators, it's always pipe primary/secondary with a single boiler pump. Oh well, what da I know.

    Question: I'm not getting it. Is the Thermostatic pump pulling all its water thru the boiler and where is the return connection from that circuit?

    bjohnhy
  • yekasi
    yekasi Member Posts: 14
    edited January 4

    Hello.  I think i may have found the issue, it seems like the problem is with the indirect hot water heater.

    This is what i tested...

    Test 1 - turn OFF water into Indirect hot water heater, leave boiler ON and water into boiler regulator ON.

    1) at 11:31PM, It was at 30 PSI and it was leaking from relief valve.  Temp was at around 165-170.

    2) i shut off cold water supply into indirect water heater.  The boiler is on, the regulator is untouched. 

    3) bleed some water from the same zone that i was using, got it down to 17 PSI.  Water stopped leaking from pressure relief valve.

    4) waited for 15-20 min, looking at the pressure every minute, and it stayed at 18 PSI.  

    5) The boiler came on once when the temp dropped to 145 (not sure how it dropped so quickly? may be because i bled some water?). It went back up to 170 and stopped.

    6) Pressure remained at 18 PSI and no leaks.

    7) At 11:48AM, i turn cold water back on and let it feed into hot water heater.  At this point it is at 18 PSI and 170F.

    8) At 11:55PM PSI went to 22 and temp is at 145.

    9) at 11:57PM PSI is at 28 and temp is at 145.

    10) at 12:00 PSI at 30 and temp at 165 and water started to leak.

    Test 2 - Leave water supply to hot water ON .  Shut OFF water supply into boiler regulator. Boiler is ON.

    1) Started at 12:02AM and it is at PSI 30 and temp at 180 after last test.  I drained water and now it is back to 15 PSI and 180Temp.

    2) 12:04AM , PSI 18 and temp at 180

    3) 12:11AM, PSI at 21 and Temp at 160 (Why did the temp drop?)

    4) 12:17AM, PSI at 30 and temp at 175. Water started dripping fast.


    At this point, i just turn the water supply into regulator back on as i believe i found the culprit.

    Now onto next question, it sounds like its not fixable, and the water heater needs to be replaced. If i have to replace the water heater, i would be interested in changing it into a gas fired water heater rather than indirect. My boiler - is also very old and i dont want to lose heat and water at the same time. Would install to switch to a gas fired be very problematic job? or it should be similar to replace a indirect? Thanks.


    thanks

  • bjohnhy
    bjohnhy Member Posts: 146

    @Grallert found the culprit.

    What city are you in? Gas rates? Electric rates? Number of showers per day for the house? How many showers /tubs in the house? How many people live in house?

  • yekasi
    yekasi Member Posts: 14

    New York Nassau county. I don’t know about the electric rate or gas rate….


    4 people and 4-6 showers a day.

  • hot_rod
    hot_rod Member Posts: 26,721

    I would go with a similar sized indirect tank if that has supplied your needs all these years?

    I don't think your DHW usage is a good match for a heat pump water heater.

    You already have a boiler, pump, piping and wiring, so the cost of the tank and labor.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    GrallertHomerJSmith
  • yekasi
    yekasi Member Posts: 14

    thank you @hot_rod

    Is there any further test i should do to further confirm it is a indirect water heater? And is this Coil replaceable rather than changing out the water heater?

    thank you.

  • Grallert
    Grallert Member Posts: 1,062

    I'll reply just cause I'm sitting here. Unfortunately the coil in that particular water heater is not replaceable.

    It looks like you've performed all the tests necessary to confer a failed indirect water heater.

    Miss Hall's School service mechanic, greenhouse manager, teacher, dog walker and designated driver

    bjohnhy
  • hot_rod
    hot_rod Member Posts: 26,721

    The coil is not replacable, did you mention how old it is? 4-6 showers a day plus other DHW use, it probably has some miles on it.

    High chlorides in the water can be tough on stainless tanks. If you were to have a water analysis do e and you see levels above what stainless tanks suggest, a steel glass lined tank is my favorite.

    Hardness, TDS and chlorides are good % to know.

    Here is the water spec from the folks that build that SuperStor tank. It would be similar for other stailess tank brands.

    Screenshot 2026-01-04 at 11.00.34 AM.png
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • HomerJSmith
    HomerJSmith Member Posts: 2,722

    My assumption is no anti freeze in your sys that may have turned acidic.