Question on Expansion tank replacement

stumblinhorse

I think my expansion tank is/has failed. Was here when I moved in and assume it is quite old. I hear rushing water when the pump turns on and the hy-vent is leaking. Need some advice on where best I need to open to release some of the pressure and drain to replace the tank. I have attached a few pictures. From the looks of it, it will be difficult to get the tank out once detached since the OWB exchanger is right in the way. So I will be drilling a hole in the expansion to drain water out. The house is new to me in the last few months and I have been focusing on immediate issues. And seems to have been an issue for a while judging from the sludge dripping down. So now it is my focus to resolve these issues .

I attached a pic of Backflow valve that is in place after the water line into the system. I am going to shut that off. Quick question is what is the vent and where should that be running to? Everything in my boiler room runs into the floor and down into a finished basement. So cannot follow it to where it terminates. So for my info where should it be going?

There are 3 valves I can open to drain(all pics attached). Boiler drain, Drain on top of hot water in manifold and drain below expansion tank and OWB exchanger.

I am uncertain which drain is best? Assume top drain will not impact the expansion tank since it is above it? So drain below the expansion tank/OWB EXC is best? Boiler drain is overkill?

I also will put in a drain and valve above the expansion tank when I am at it to make it easier, if there is room!

Thanks for any help

Jellis

Hello, Rushing water when the pump turns on and a leaking hi vent does not mean your expansion tank is bad.
Wrap on the side of the tank near the bottom and then again on the top, you should hear a difference in the sound as the top of the tank should have water and the bottom should have a cushion of air. If the whole tanks sounds solid and full then you may have a failed expansion tank air bladder and yes you need to replace.
You will need to replace your air vent to stop the leak, when you re-fill the system you will need to purge the system.
When your system is properly purged and the air vent is fixed that should solve your rushing water issue.
If your unsure about how to drain your boiler, my advice would be to call a pro properly
purging the air from the heating loops is necessary for your system to work.

stumblinhorse

Thanks for the reply. The whole "call a pro" thing doesn't work here. I have been trying to get my indirect hot water heater replaced over the last 2 month and have been unsuccessful trying to get someone to come. I got 1 quote of $. The last person I honestly did offer higher trip charge (1hr from their office) and they said no that they have all the business they can handle within 10 minutes.

So I am on my own and quickly learning about boiler systems. The expansion tank is original, judging by the date code on it, it is from Dec 2000. Might not be failed, seems to still have a hollow sound on the bottom. But I am trying to make sure that things that were neglected are addressed before they fail. So if you think 19 years on an expansion tank is still ok, then I can leave it.

Jellis

Where are you located? someone here may be able to refer you to a company.

If you must try yourself then you can drain from the boiler drain, Isolate all of the zones if you can, Supply and return, you only need to drain the water back from the vent. Fill the boiler again until all air stops coming from the vent, open your zones back up and you should be good to go.

stumblinhorse

I have left messages or talked to 40 plumbing companies. Ranging from 20 miles to 50 miles away. I think in most areas it is not normal. So not needing to talk more about getting someone to come by. Trust me, I have tried to the point of being absurd... I am a do it yourself person and have always done things myself. So I am going to just give it a try tomorrow. Picking up what parts I think I need to replace and give it a try.

Not sure why I would use the boiler drain. I need to drain so little off, I am going to use the drain at the top of the manifold. My biggest things to figure out is to me it looks like the fill control valve makes the removal of the expansion tank with the valve attached impossible. Looks like the water inlet needs to be cut to allow the expansion tank w/control valve to unscrew from the Taco air scoop. Looks like that is a simple compression fitting but there is no movement in my install for that pipe to pull away from the inlet pipe. Probably why it has never been replaced, along with the fact that there is not enough room below the expansion tank to actually remove it from that area. The only way is to move it directly to the right and then up to the ceiling and over and out !

JakeCK

If your expansion tank is a Fill-trol, it should just unscrew, and if I remember correctly, and I really could be mistaken on this detail, it is designed to close the valve once it unscrews enough so you don't even need to drain the system.

Snowmelt

Where from?

STEVEusaPA

Going to need more pictures, can't see the whole thing. Can't tell if it's connected to the supply, the return, or where the shut-off valves are located.

Going to sound harsh, but maybe it's you or some other extenuating circumstance. Maybe the reason why you aren't having much luck with any professionals as it seems you like to tell them what the problem is before they get there. I find it hard to believe that 40 plumbing companies aren't interested. Also @jellis asked you where you are located, city/state. Should be a 1 hour job if you can get at it with a propress.

Like @Jellis mentioned, there is no evidence that there is a problem with the expansion tank. Unlike what he said, banging on it isnt a professional, or accurate way to check it.
Only way is to completely drop the pressure, or isolate it, check it.
For a quick check you can depress the schrader valve to see if any water pops out.
But being you have to replace the poor excuse for air elimination anyways, I'd drain the system, cut the copper on both sides of the horrible, incorrectly installed air scoop. Get a bracket and attach the expansion tank to the wall. Once the system is drained you can determine if you can reuse the exp tank or get a new one.
Use a Webstone expansion tank valve, for easy service/checking and future replacement.
Use a modern micro absorber air eliminator in place of the air scoop.

Steamhead

@stumblinhorse , where are you located?

JakeCK

Looking at the fill-trol install PDF. I think I was mistaken about how it shuts off the valve. But it does just thread on and off of the valve.

Everything you said you want to do is really easy on your setup if all of the plumbing heads into the floor. The auto vent unthreads and so does the expansion tank, and they all look as if their at the top of the system so little water has to be removed. Once you take off the expansion tank it is really easy to tell if its bad. If it is light with no water and you have correct pressure on the valve stem it is good. If its bad it will be full of water. Don't ask me how I know.

https://www.amtrol.com/wp-content/uploads/2019/03/9015-026-01_19-Fill-Trol-IO.pdf

stumblinhorse

Well thanks for all the replies. Both me and my wife have called for plumbers. She called 6 today, I stopped because I know they won't come. Got calls back from 3 and all 3 said not interested, they are too busy working on new construction and no longer do service calls. They don't need to, they have a years worth a work already lined up on new construction. I live in Kremmling, CO. All trades around here are giving signing bonus for people to come to work here. No one wants to work on 20 year old stuff and really they don't have to to stay in business.

I agree the expansion tank should unscrew, but should I also replace it with the same model 110 that has the fill control valve top? As you can see from the attached pic, the inlet is coming in on the top of the expansion . It would have to be cut to unscrew the expansion with fill control from the air scoop.

stumblinhorse

STEVEusaPA said:

Going to need more pictures, can't see the whole thing. Can't tell if it's connected to the supply, the return, or where the shut-off valves are located.

Going to sound harsh, but maybe it's you or some other extenuating circumstance. Maybe the reason why you aren't having much luck with any professionals as it seems you like to tell them what the problem is before they get there. I find it hard to believe that 40 plumbing companies aren't interested. Also @jellis asked you where you are located, city/state. Should be a 1 hour job if you can get at it with a propress.

Like @Jellis mentioned, there is no evidence that there is a problem with the expansion tank. Unlike what he said, banging on it isnt a professional, or accurate way to check it.
Only way is to completely drop the pressure, or isolate it, check it.
For a quick check you can depress the schrader valve to see if any water pops out.
But being you have to replace the poor excuse for air elimination anyways, I'd drain the system, cut the copper on both sides of the horrible, incorrectly installed air scoop. Get a bracket and attach the expansion tank to the wall. Once the system is drained you can determine if you can reuse the exp tank or get a new one.
Use a Webstone expansion tank valve, for easy service/checking and future replacement.
Use a modern micro absorber air eliminator in place of the air scoop.

That is where my head is at, I want to have some trust in the system going forward. So far it has been nothing but a headache. I have the a HTP SSUltra 45G ready for install. So when I do that I will have the system drained. I might as well cut more copper and redo what is done wrong.

JakeCK

> @stumblinhorse said:
> Well thanks for all the replies. Both me and my wife have called for plumbers. She called 6 today, I stopped because I know they won't come. Got calls back from 3 and all 3 said not interested, they are too busy working on new construction and no longer do service calls. They don't need to, they have a years worth a work already lined up on new construction. I live in Kremmling, CO. All trades around here are giving signing bonus for people to come to work here. No one wants to work on 20 year old stuff and really they don't have to to stay in business.
>
> I agree the expansion tank should unscrew, but should I also replace it with the same model 110 that has the fill control valve top? As you can see from the attached pic, the inlet is coming in on the top of the expansion . It would have to be cut to unscrew the expansion with fill control from the air scoop. (Image)

You shouldn't have to cut anything. The makeup water supply should use a compression fitting on the valve. Turn off water supply, and use a wrench to loosen.

Steamhead

Not far from Denver. Used to be someone on here from Denver but I can't remember his name....................

stumblinhorse

JakeCK said:

You shouldn't have to cut anything. The makeup water supply should use a compression fitting on the valve. Turn off water supply, and use a wrench to loosen.

I agree it is a compression fitting. But there is no room to pull the pipe out away from the fill control valve. The inlet pipe is right above and the expansion tank is not going to move any. Not sure if it is possible to turn the fill control valve with the pipe right there. I guess I will have to try it.

mars_6

You might try Heatmeister Heating Service, he is out of Dillion and may be able to come up and check it out. Unfortunately there just aint many good service companys up around them parts.

Jellis

Like @Jellis mentioned, there is no evidence that there is a problem with the expansion tank. Unlike what he said, banging on it isnt a professional, or accurate way to check it.

@STEVEusaPA
I agree its not an accurate way to check the pressure in the expansion tank, however its a quick and easy way to find out if your tank is maxed out or the bladder failed.
Checking the air pressure of the bladder certainly is the right thing to do! I should have included that in my answer.

I hope its not considered unprofessional, I thought it was law to flick the expansion tank when you go into a basement?

STEVEusaPA

You can do it anyway you want.

I have heating oil customers on auto delivery call me stating their heat is off, and they 'banged on the oil tank, and it sounded empty', even though the gauge is showing they have oil. I check my records and they have plenty of oil. So it's a service call and not a wasted trip in the oil truck.

I wonder what's going on up there with contractors and all the new work. Sounds like a gold rush of sorts. Got to be some HVAC company that does service/repairs.

I guess when the new work is done then the companies will be begging for service work.

I wonder if the recuperating @Mark Eatherton knows of someone.