1960s boiler heater questions


  #1  
Old 09-24-22, 09:09 PM
N
Member
Thread Starter
Join Date: Sep 2022
Posts: 6
Likes: 0
Received 1 Like on 1 Post
1960s boiler heater questions

I have a few questions for anyone who has time or interest and patience to help me.
I am relatively new to all of this. I have owned this home for a little over a year and have been told I need to replace this old expansion tank with a new bladder tank, but money is really tight right now and for this year would just like to empty the current expansion tank and top the system back off the boiler to an appropriate pressure as the pressure is currently low after bleeding all of the heat registers.
From the videos I have watched this expansion tank maybe doesn't have the proper valves. I know this is a very old system but it has provided this home with heat for years, was very reliable last winter and I hope it has a few years left in it.

I am going to attach pictures below of the boiler and if anyone can give any suggestions, I appreciate it.

For emptying the expansion tank am I correct in thinking all I have to do is release the screw to the right, of the picture of the expansion tank? I wish it had a valve that was easier to open, but I also think it should have a valve I can close on the opposite side to ensure that the entire system does not drain out this tank?

For refilling and topping the boiler system off, am I okay to just fill in through the valve at the bottom? Last year I think I filled it too high as I was going to be gone for a while and was afraid of the system getting low, and I think that is why the expansion tank got so full.

Thanks in advance for any information and for your patience.
Thanks, Tom
 

Last edited by NewHomeOwnerND; 09-24-22 at 09:34 PM.
  #2  
Old 09-25-22, 08:10 AM
2
Member
Join Date: Jan 2014
Location: USA near Boston, MA
Posts: 2,002
Received 282 Likes on 241 Posts
Although I do not have "hands-on" experience with such tanks, I did some research last year when I ran into one in a system posted on this site.

Google "Airtrol air valve" and you will find sites with diagrams and descriptions of how it works. You should be able to find instructions about how to drain and recharge the tank.

Basically, the air valve at the bottom of the Airtrol lets air in through a tube that extends up into the tank. I believe you are correct that the screw valve on the right is to drain water out. Most that I have seen have a standard valve at the end of the tank.

I believe the simple explanation is that the water comes from the boiler. You do not have to fill the tank separately. The air in the tank provides a buffer to offset pressure changes as the water in the boiler and system gets hot. If there is no (or not enough) air in the tank, the boiler pressure safety valve will open to relieve pressure.

There should be an isolation valve in the piping between the boiler and the tank. Close that valve and drain the tank (partially) according to the Airtrol instructions. (Upon further review of your photos I do not see an isolation valve. Can you provide a photo of the end of the tank where the 2 pipes rise? There is probably a way to create isolation by reducing pressure in the system but I cannot tell from what I see. Possibly using the valved stub coming off the air separator. But that configuration looks weird to me.)

After some water is drained and air is let into the tank open the isolation valve. If the system pressure does not restore to about 12 pounds (where the red reminder indicator is on your gauge) add water to the system.

I do not see an automatic fill valve. I think your water supply is the valve that has no handle feeding into the tank pipe.

Also your gauge shows that the system is not pressurized enough. It should be between 12 and 20 pounds.
 
  #3  
Old 09-25-22, 08:52 AM
N
Member
Thread Starter
Join Date: Sep 2022
Posts: 6
Likes: 0
Received 1 Like on 1 Post
Thank you so much for your time,
I agree I don't think that there is no isolation valve between the boiler and the expansion tank. I was hoping the aritol valve thing took care of this somehow but will need to Google that valve like you suggested.

I will take some more pictures and post them to make things more clear. This system is also connected to an old cistern that is connected to the boiler. I had a plumber out last year that told me to fill the boiler, when it was time, through the cistern. The cistern is filled with very nasty rusty water drained from the house roof and is pumped out with a pump that is from 1986 that takes a lot of effort to get running and I could not see filling the boiler with that very rusty and questionable water, so in an effort to keep people from trying to fill the boiler with this water in the future, I removed the handle. When I had the plumber out last year to fill the boiler with antifreeze (even though it turns out it was already filled with antifreeze but that was never checked/tested and it was just assumed there was only water in it) but I was very naive and nervous coming into my first winter of home ownership, but the old antifreeze was thrown out and new antifreeze was pumped in) he filled the antifreeze through the valve closest to the ground. I tried to ask questions but it was clear he didn't want to explain anything and even seemed annoyed I was trying to watch and learn. Maybe he was just having a bad week but I needed someone who was more willing to teach me about what I was working with. He did change out a valve on the back side that he was then able to connect a hose to when he was switching out the antifreeze, that will be the last picture on the next post. I think the idea behind that was to drain the fluid out at the same time the new antifreeze was getting pumped in?
I'm sorry if this isn't very clear and will try to clarify anything that doesn't make sense. Much of this house was not done by professionals, so things that you are looking at are probably not done correctly as you surmised. All I could really get out of the plumber that worked on this system last year when he looked at the expansion tank part of the system was, "hmmmmmmm" which I took to mean things weren't right. At that time I didn't even know what a "closed" system was which I now understand this to be.
I do now have a pump and hoses and boiler antifreeze from supplyhouse.com and am slowly getting more comfortable with all of this. I do think I need a professional to eventually change out this old expansion tank with a bladder tank or add an isolation valve so this tank can be emptied and refilled properly, but if I can get this tank emptied on my own for this next heating season, that is pretty much my option this season as I am about maxed out on my credit. Surely over the last 60 years this tank has had to have been emptied multiple times, though if that was the case it seems like there would be a valve instead of that screw, which i think is going to make things very hard and messy with all of the pressure that the antifreeze is going to spray out with.

Thank you again so much,
Tom
 

Last edited by NewHomeOwnerND; 09-25-22 at 09:12 AM.
  #4  
Old 09-25-22, 09:27 AM
2
Member
Join Date: Jan 2014
Location: USA near Boston, MA
Posts: 2,002
Received 282 Likes on 241 Posts
Is anti-freeze in hydronic heating systems standard in ND. Or do you have extended power failures and potential freezing? If you have a potable water source (well, municipal) adding a connection may be possible and easy at the stub I mentioned. The cistern supply would have to be cut off from the potable water supply by more than a valve.
 
  #5  
Old 09-25-22, 09:36 AM
N
Member
Thread Starter
Join Date: Sep 2022
Posts: 6
Likes: 0
Received 1 Like on 1 Post
Yes, there are sometimes prolonged power outages. I live in a rural area so plumbers are traveling a half hour at a minimum to make it out here and sometimes an hour of the closer guy can't make it out, so being just 7 miles south of Canada with how cold it gets it was recommended that there be antifreeze in the system as I was told I would not be able to afford replacing the pipes or heat registers if they were to crack open apon freezing if I could not get anyone out to work on the system should it fail, or if the power were to remain out for an extended period of time, which sometimes does happen.
The house is hooked up with rural water and is not connected to the boiler. The cistern is not hooked up to the current water heater. The cistern currently only has a line going to the boiler and to two faucets, one that leads outside to the back of the house and one that leads to the wall of the basement.
 
The following users liked this post:
  #6  
Old 09-25-22, 10:38 AM
2
Member
Join Date: Jan 2014
Location: USA near Boston, MA
Posts: 2,002
Received 282 Likes on 241 Posts
Good reasons to have anti-freeze. Of course when necessary you still have to drain the other pipes in the house to prevent them bursting. Unless you have a backup power supply the boiler will not run.

Keep in mind if you ever size a new boiler to replace the existing that glycol/water carries slightly less heat than water alone so boiler needs to be sized accordingly.

I presume the feed from the cistern is by gravity. Unless it is pumped you will not be able to create enough pressure in your boiler system. If you do have a pumped cistern and want to use it for the heating system you should probably filter it.

You can obtain water for your boiler from the same pressurized cold water source that feeds the water heater. The demand for water at the boiler is incidental and will not affect the hot water supply to the house. An automatic fill valve could be used but would be subject to freezing in abnormal circumstances.

Rudimentary plumbing skills should be enough for you to DIY most of what needs to be done. Can you solder copper pipes? Check some videos online to learn the basics. Also Sharkbite fittings can be used.
 
  #7  
Old 09-25-22, 11:41 AM
Z
Member
Join Date: Jan 2008
Location: Southeastern Pennsylvania
Posts: 3,652
Received 87 Likes on 81 Posts
Hi guys -

I read the posts, but unfortunately at my age now my eyes see - but sometimes my brain is somewhere else – lol! So the questions I have may not be relevant. But –

(1) Why do you need a new expansion tank? I have an overhead steel expansion tank and as far as I know those work fine. There is nothing inside as far as I know that would fail. They are empty. As far as I know you would not need to replace the tank unless it was rusted through and is leaking. Mine has been there 20 yrs. since I lived here and who knows have many years before that.

(2) Why do you want to periodically drain the tank?

(3) Why didn’t the plumber drain a very small amount from your boiler and see that it contained antifreeze? Couldn’t he test it and determine whether or not you really needed to replace it? It seems like that could be done. But maybe not.
 
The following users liked this post:
  #8  
Old 09-25-22, 11:54 AM
2
Member
Join Date: Jan 2014
Location: USA near Boston, MA
Posts: 2,002
Received 282 Likes on 241 Posts
A block diagram of your system will be helpful to us for advising you, and to you for modification and maintenance issues. Show all major items and mfgr./model numbers. Show piping up to where it goes out to and comes back from the radiators, water supply, etc.. You do not need to show them but telling us what the emitters are (cast iron radiators, CI baseboards, copper fin tube, etc.) will also help.

 
  #9  
Old 09-25-22, 01:14 PM
N
Member
Thread Starter
Join Date: Sep 2022
Posts: 6
Likes: 0
Received 1 Like on 1 Post
Zoesdad, I agree with you, the plumber should have tested the system, and he did test it when he was done, but told me he needed to come back in a couple weeks to put more in. By this time I had already waited half a month for him to come out and didn't have more time last year to wait around for him, so never had him return. I think he had it in his mind i didn't know anything (I didnt) and it was a good way to make money. I feel if I live in the middle of nowhere I need to be able to figure out as much of this as I can, if for nothing else, know when I am getting taken advantage of.

I was told by a coworker to get it switched to a bladder expansion tank so I don't need to worry about trying to empty the tank in the future. I need to empty it as it is water-logged, from what i can tell, and don't want the system exploding if there is no room left for the water to expand and if the relief valve were to fail. But I think you are right, if I can comfortably empty the tank when it gets like this maybe I don't need to change it to anything more modern just yet.

I will eventually try to get a diagram drawn, thank you for the suggestion, John. The radiators in the house are of the old cast iron types, except in the bathroom and a small office that had formerly been a part of the kitchen. Those have the newer fin style radiator. I was able to bleed all of them this spring (something the plumber never even mentioned should be done but found through research that was why the system was making so much noise upstairs) After I bled the system, the pressure dropped, and my attention to the boiler got put on hold for the summer. I had hoped to get a guy out to service the entire system this fall, and still may need to do that, but if I can empty the expansion tank myself, I have the pump and the antifreeze to put more into the system and will be ordering the PH test strip from supplyhouse.com to check the level of the antifreeze.

Thanks again to all!
 
  #10  
Old 09-25-22, 02:20 PM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,383
Received 119 Likes on 113 Posts
NHO,
Z has made some valid points and there is nothing wrong with his mind or your tank. It looks like you have a couple of piping issues which could be solved I believe without removing your tank.

That Red valve in the tank is an Airtrol and that screw in the bottom is to let air in to break the vacuum so water can be drained out. The plug at the end of the tank to the right of the ATrol should be removed and replaced with a boiler drain. There should be a shutoff on the pipe before the AIRTROL to isolate the tank from the system for draining.

Z made a good point when asking why you drain so often. If done right it could last for years if the system isn't opened and also you should be able to take a sample of your antifreeze yourself and have it tested. No plumber needed for that.

The pipe from the sistern can be cut above the elbow and relocated to your potable cold water line and a boiler feed valve along with a backflow preventer if required and another shutoff so it can be isolated if need be.

That RED valve on the side of your boiler is where your fresh water comes into the boiler along with the expansion tank and then is your supply to your emmitters. You have 2 FLOCKECK VALVES at the top by the tank. One has been cut or is an extra in case you want to add another zone.

As far as boiler pressure that is where your feed valve would come into play setting it auyomatically along with your tank. As you pressurize your boiler you pressurize your tank at the same time.

With everything to cover I don't know if I got it all but I hope this helps a little.

One final point I missed. When you drain your tank you MUSTdrain it COMPLETELY. If you don't it will just refill from where you left off and you will be worse off than before so be patient and make sure it is all out. If you don't have the time to wait you are better off waiting. If it gets full the only thing that will happen is your frelief valve will let go at 30 psi but in your case could get expensive with the antifreeze.

Just saw your latest post about him coming back to add more antifreeze. The thing about that is when he adds more AF it will raise your boiler pressure unless he lets some water/AF out before he does it. You complete the job once you start.

 

Last edited by spott; 09-25-22 at 03:01 PM.
The following users liked this post:
  #11  
Old 09-26-22, 07:53 AM
N
Member
Thread Starter
Join Date: Sep 2022
Posts: 6
Likes: 0
Received 1 Like on 1 Post
Thank you all,
I am still learning and understanding this system and your input has helped. With the expansion tank not having a site glass it's hard for me to tell how full it is. I remember it feeling very full, but as I tried to lightly shake it (also trying to be careful on it so I don't screw up the connections) it does not seem full... and maybe that is because the pressure is currently so low in my boiler? My understanding was once the tank was "water logged" the only way for the water to come out of that tank was to manually remove it.
I will aquire PH test strips to see if I need to fill the system with more antifreeze or water, and will be using the pump to fill it with whichever is needed to get the pressure in the boiler up to the appropriate level. If the expansion tank seems to fill during this process I think I will call someone to come out to look at the system with professional eyes and to make the appropriate steps. I want to do things myself where I can but it is so much easier for me to learn by watching and asking questions in person. I am by no means a smart man, and I know this.

I know there is water in the system that was just from the house tap, used with a hose and connected to the drain at the bottom of the boiler, but from now on when I fill it will use distilled water to try and keep things as clean as possible inside the system. Eventually I would like to drain it all, run a cleaner through the system, and fill it again, but since I spent $1500 on it last fall getting antifreeze pumped into the system I hope it will all be okay the way it is for a half decade or more before I get to that point of draining it and cleaning it. I know oxygen in the system is bad, which there was a lot of as every heat register this spring had a large amount of air that was released. After I top the boiler off I will try to bleed each register again to make sure there is not air sitting up in those lines.
Thank you again for all input.
 
  #12  
Old 09-26-22, 03:56 PM
2
Member
Join Date: Jan 2014
Location: USA near Boston, MA
Posts: 2,002
Received 282 Likes on 241 Posts
will use distilled water to try and keep things as clean as possible inside the system
Not necessary and a waste of money. Hot water for heating does not have to be clean. Over time the oxygen will dissipate and there will be minimal oxidation of iron pipes. Because of this the water usually looks black rather than brown rusty. Tap water or clean cistern water (filtered?) along with the glycol should be fine.

Cleaning and refilling is not necessary and introduces oxygen rich water into the system. When the water heats up the oxygen is released and causes the air bubbles at the emitters that you have to bleed. Draining the expansion tank completely lets it fill with air to act as a pressure buffer. That air has minimal contact with the water in the system and will not get re-entrained into the water.
 
  #13  
Old 09-28-22, 07:40 AM
2
Member
Join Date: Jan 2014
Location: USA near Boston, MA
Posts: 2,002
Received 282 Likes on 241 Posts
Several more thoughts

If you need to drain water/glycol from the system, you can save it for reuse. A neighbor at my vacation home used a glycol mix in his heating system. He kept a 55 gallon drum handy to transfer the liquid into when necessary. If your drain valve is low, you may need a small pump.

You might be able to raise the pressure in your system AND partially resolve the waterlogged tank issue by introducing compressed air into your expansion tank. A Schrader valve would be useful but you might be able to do it through the Airtrol.

If you need to introduce only a small amount of fluid to increase the system pressure and do not have any reusable mixture available just pump in some more glycol rather than water. It will increase the concentration and lower the freezing temperature.
 
  #14  
Old 09-30-22, 11:43 PM
N
Member
Thread Starter
Join Date: Sep 2022
Posts: 6
Likes: 0
Received 1 Like on 1 Post
Very useful information for me, thank you again, John!
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: