Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

hot water boiler issues

Options
dreads
dreads Member Posts: 17
First I have a Thermo Dynamics S series oil fired boiler about 25 years old.
There are three heat zones lower level den small zone, 1st and second floor large main zone and upper level bedroom small zone
The problem I've been having for the last three years is no heat on the second floor of the main zone. seems the pressure was too low too push the water up to the second floor. The issue was compounded by the fact that the pressure part of the gauge never changes from about 12 and I believe it isn't functioning. In the past by playing around with the pressure regulator valve for the water, it seemed as if it was stuck and not letting any water enter. after messing with it I felt the cold water flow in and after bleeding, the heat began coming up on the second floor.
Again this year I had the same issue and result except that the boiler pressure valve has pissed off some water 2 or three times in 2 days. I would like to solve this issue. I went out and got a test gauge that I was able too hook into one of the lines where there had been a plug so I could monitor the pressure. There is no doubt the original gauge is broken.
When the boiler isn't running but is on, the new gauge reads about 20 psi when the boiler goes on and heats up it hits about 26 lbs which seems high. not sure why it let out water??
I have tried adjusting the regulator valve but it doesn't seem to have any effect. When I drop the pressure to 0 psi it will then refill to about 20 psi at idle
The pressure safety valve now has a steady flow of water about 1 gal/8hrs.
I would welcome any ones thoughts on this whole matter. Thanks

Comments

  • kcopp
    kcopp Member Posts: 4,432
    Options
    Sounds like the expansion tank is water logged. System needs some tlc.
    Intplm.
  • Intplm.
    Intplm. Member Posts: 1,947
    Options
    Sounds like you have a few problems that can be solved.
    your second floor zone needs to be purged.
    Can you send a few pictures of your boiler to help communicate things better.
    Would also like to see your thermostats.
    You have three of them? Correct?

  • HVACNUT
    HVACNUT Member Posts: 5,834
    Options
    Most "water" parts on a boiler have a life expectancy.
    The PRV, extrol, 30 lb relief valve, auto vent.
    If they're original, it's time to replace all.
    The home is a split level. Is the main and second floor zone split into 2 seperate loops at or near the boiler? 2nd floor loop could be air bound.
    Replacing the water parts and purge all zones separately should do it if...
    If theres not a hole in the tankless coil.
    Keep in mind, a 25 year old dry base steel boiler is no spring chicken.
    Jean-David Beyer
  • dreads
    dreads Member Posts: 17
    Options
    Thanks all
    First I posted some pics
    kcopp mess with the tank or just change it?
    INTPLM I have three 120v thermos. At one time I looked into new ones but it turned out to be complicated because of the 120v when you say Purge 2nd level? when I bleed the radiators at this pressure every thing works fine heat wise?
    hvacnut I believe everything except one or two of the circulator pumps and the burner itself is original. The home is 5 level including basement. the boiler itself actually seems to be working fine
    Some questions do I mess with the expansion tank or just change it. If the safety valve continually drips is it shot? I tried manually releasing it twice in the hope it would reseat and stop dripping to no avail anything else I can try.
    If I drop the pressure to zero and let it refill itself it goes to 20psi. Is the regulator valve shot? I have tried adjusting it lower.





    Where do I start?
  • dreads
    dreads Member Posts: 17
    Options
    The automatic air vent in the very top right of the third picture is dripping I will change that first any recommendations as to brands? Thanks
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    Options
    You need some help. Very hard to diagnose over the internet. It's hard to try to see what's going on without being there. Something that can be figured out in 10 minutes will take 2 days of back and forth questions and answers, photos, etc.

    Expansion tank needs to be isolated and checked.

    If....IF, that boiler is 25 years old (has to be older), the burner is much older, and as far as I can tell, never offered with that boiler.

    I guess the installer bought the boiler without a burner and re-used one.
    steve
  • dreads
    dreads Member Posts: 17
    Options
    STEVEusaPA I've been in the house 33 yrs boiler was put in 4 to 7 yrs later and yes they probably used the existing burner as the oil company replaced the whole unit under my service contract free.
    For the cost of a new expansion tank $ 34 to $ 50 doesn't it pay me to just change it. Also please recommend a brand of automatic air vent? That is a quick Item to change. Thanks
  • dreads
    dreads Member Posts: 17
    Options
    Is there a special gauge to check the charge on the expansion tank. The ones I use for the car doesn't seem to be working?
  • Intplm.
    Intplm. Member Posts: 1,947
    Options
    If It's not working ?Or showing air in it. The tank is water logged and not working. It should have a charge of 12-15psi
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,520
    Options
    @dreads

    Can't tell for sure without more information but your expansion tank is probably bad. I would install a new expansion tank. A valve between the expansion tank and the system is a good idea. A tee with a drain valve installed between the expansion tank and you new shut off valve is also a good idea.

    If your house is two stories or less you fill pressure should be about 12-15 psi. The expansion tank removed from or isolated from the system should be 12-15psi. These two things should match (fill pressure and expansion tank pressure).

    Without a cushion from your expansion tank you will get no heat then you ad water and get heat then your relief valve blows off.

    You should be able to adjust your feed water pressure to match the expansion tank. If not replace the feeder.

    You can buy Taco hi vents at Home Depot, Lowes or a good hardware store. Probably the feeder and expansion tank as well
  • dreads
    dreads Member Posts: 17
    Options
    The gauge isn't getting any reading. It is a standard car tire pressure gauge
  • neilc
    neilc Member Posts: 2,703
    Options
    dreads said:

    The gauge isn't getting any reading. It is a standard car tire pressure gauge

    right, because there's no air in it cause it leaked, or someone let the air out, or it's old and tired and needs replacing.
    You could try to recharge it.
    But you need to isolate it from the rest of the water system either by valve, or by removing/unscrewing it from the system.
    Caution, it will be heavy.
    Then, recharge it to 12~15 as written above.
    If you don't understand this then maybe you should have someone come in and do this.
    Depending on your system and valving you could end up draining it down and letting air in.
    Are you prepared for that?

    known to beat dead horses
  • dreads
    dreads Member Posts: 17
    Options
    Neilc I'm pretty handy in particular plumbing wise. Don't know a lot about boilers so before I try any thing I like to get as much info and opinions as possible. I have changed 2 of the circulator pumps over the years and added a forth "zone' to heat my pond. Right now with the heat working good Unless I have to change out something I will wait till it warms up a little just in case. What would be your recommendation for a tank and valve brand? Right now the pressure valve seems to have seated and isn't dripping "but" . Thanks
  • neilc
    neilc Member Posts: 2,703
    Options
    yeah,
    you could wait for weather to break,
    in the meanwhile,
    ya kinda want that tank charged, what boiler pressure do you see right now?
    12 ~15 ?
    add 2 more #s and try pumping up that much air into the old tank, if it holds it gives you back some expansion space,
    at worse you go google extrol tanks and read what you're getting into.
    post pictures
    known to beat dead horses
  • HVACNUT
    HVACNUT Member Posts: 5,834
    Options
    Can I interest you in scrapping the boiler and the Bock water heater for an EK-1 or a three pass boiler and indirect?

    Replace the water parts.
    1- Taco PRV
    1- Taco 400 vent. For the top of the boiler. I would plug the one on the high return.
    1- #30 Extrol. With valve and drain as mentioned above.
    1- 3/4 Male, 30 psi relief valve.
    Through in a new tridicator gauge while your at it.
    I use tephlon tape only with these parts.
    If you can valve off the returns and make sure the flo valves are tight, all you need to do is drop the pressure to 0 and change everything "on the fly" with barely a drop spilled. It's all in the prep.

    Just when I thought I'd never see an Aero burner again.
    kcopp
  • dreads
    dreads Member Posts: 17
    Options
    HVACNUT you certainly could interest me in an EK-1 send it over I will pay the shipping. LOL
    Although the gas company just ran the line up my street.
    This tank? AMTROL 102-1#30 EX-30 30 Extrol Expansion Tank
    I believe If I shut down all the valves I can do this on the fly one item at a time without losing hardly any water
    Any particular brand of tridicator gauge?
    That Aero burner has done it's job for years with no issues.
    The boiler is running about 18psi

    Once when I lived in the city a plumber changed the main water valve On The Fly
  • Intplm.
    Intplm. Member Posts: 1,947
    Options
    First, shut the water off to the boiler and isolate the supply and return zones by shutting off all of the valves. Turn off the power.
    Then relieve the pressure. The tank is water logged so it will be pretty heavy. Then you should be able to replace the tank.
    Tridicators are all pretty good, burnham, honeywell or equivalent brands can do fine.
  • dreads
    dreads Member Posts: 17
    Options
    After watching the gauge function for a while it is running about 20 psi at idle and climbs up to 26 at full heat. I think my main issue right now is the PRV has a constant flow when the pressure is very low almost nothing Over 20 psi a gal. every 4-5 hrs. Monday I will change the PRV?
  • DZoro
    DZoro Member Posts: 1,048
    Options
    You need a new pressure tank, its failure is causing the prv to open.
    D
    kcopp
  • dreads
    dreads Member Posts: 17
    Options
    DZoro do you think that even if it is dripping at 10 psi it may not be the valve and I should change the tank first?
    kcopp
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,520
    Options
    Caution a water logged ex tank is heavy. No broken toes. Be prepared to hold a tank full of water. If your changing it you could isolate it and drill a hole in the bottom to drain it and make it lighter
  • DZoro
    DZoro Member Posts: 1,048
    Options
    Sounds like the prv valve is not seating anymore, change both.
    D
    kcopp
  • dreads
    dreads Member Posts: 17
    Options
    I was going to change the expansion tank today but since Tue. and wed. are supposed to be brutally cold I decided to hold off. In the meantime I shut all the valves, released the press. and changed the vent on top of the boiler to a Taco and per HVACNUTs advice removed and plugged off the upper one. Probably thurs. or Fri I will change the tank. Thanks to all who provided advice greatly appreciated.
  • dreads
    dreads Member Posts: 17
    Options
    I wasn't going to attempt this repair until it warmed a little but murphy had other plans. On monday late eve I found a puddle in the front of my basement turns out the return pipe to a first floor radiator was leaking pretty good. I turned off the boiler, closed the valve on the radiator disconnected the line from the
    Tee
    and capped it. I should be GTG. Restart boiler turns out the old valve isn't quite holding and water is still coming out the other line. shut everything down again disconnect and cap the other line GTG. Restart, something not right PRV valve blowing off. Turn boiler off. In the morning change PRV, expansion tank restart no water coming in, shutdown removed AFV totally clogged virtually no water getting through replace AFV every thing good. Now for the radiator LOL