Gravity supply tank replacement

guzzinerd · October 2023

Hey Guys,

Hope your summer was good.

A neighbor heard about me tuning up our old steam system and asked if I would go over and make sure her old boiler was ready to light up (pilot).

Since her's is a hot water system and I've only worked on my steam model I thought I'd share some pics and ask what else we should be checking before lighting the pilot. (normally she left it on during the summer but with the hot summer we had this year she turned it off).

Also, I included the pics of the beautiful old gauges since I have no idea what their settings should be set at.

Thanks!

HVACNUT · October 2023

Is that in the kitchen?

And I don't understand the piping on the radiator. Return goes up?

leonz · October 2023

Your neighbor is blessed with a simple heating system. She is the proud owner of an overhead gravity hot water heating system.

guzzinerd · October 2023

HVACNUT said:

Is that in the kitchen?

And I don't understand the piping on the radiator. Return goes up?

Yes, which is why she turned off the pilot this year.

leonz said:

I think she is blessed with a simple heating system as she is the proud owner of an overhead gravity hot water heating system.

All the feeds come from the attic so that's what I figured. Anything I need to check before firing it up? Water levels, pressure etc?

Thanks

leonz · October 2023

The pressure in the system now is the result of the water weight above the boiler and additional pressure will only occur when that beautiful little boiler is fired.

Make sure you ask your neighbor how her heating system is filled with water and where it is filled and
you need to reach the attic to check the water level in the open to air expansion tank.

1. If the system is filled from the basement there is a water line rising to the attic and there should be a drain line coming from the open to air expansion tank in the attic to the basement leading to a laundry sink or a nearby floor drain that will indicate when the tank is filled to its top level as the water is draining back to the basement. When you have water draining to the basement you need to shut the water off.

2. If the system is filled from the attic there is a water line and valve buried in attic insulation near the expansion tank. There should be a sight glass in the tank or perhaps a boiler drain in the side of the tank to indicate the water level in the open to air expansion tank.

If the attic is fully insulated and the system has a saddle tank in the attic connected to the roof trusses you treat the filling of the system the same way.

I would love to see more pictures of her beautiful heating system from the basement to the attic.

guzzinerd · October 2023

Thank you @leonz

Looks like the water feed is behind the boiler, the valve is shut. I don't see any site glass

The tank in the attic is completely wrapped in insulation and don't see anything underneath in the basement.

guzzinerd · October 2023

Pilot light won't fire up. Gas is turned on, can't heat it when pressing down on the pilot button. Ideas?

JUGHNE · October 2023

How many stories is the house?
The boiler is on the main (1st) floor?

That is an altitude gauge and is showing about 8-9 feet of height.
(It is also one that you want to tap on the side with a tool to see if the gauge is stuck).

You could add a hose connected gauge to the drain valve on the back of the boiler.

Those attic tanks had a pipe connected to the water heating main and then possibly an overflow pipe that was connected to the drain system of the house or maybe a visible drop into a basement sink or drain.

It looks like it also has an overflow up thru the roof. Would be the only pressure relief valve, maybe.

There were some systems that had 2 pipes so that the water would circulate thru the tank to prevent freezing. So the second one might not be a drain.

The tank should be about 2/3 full maybe.

If you added water and the altitude gauge changed then it might be correct or at least functional .

guzzinerd · October 2023

It's a small single story home, probably around 800-900 SQ/f

What altitude is the gauge measuring? Because we're at almost 7000 feet.

JUGHNE · October 2023

The altitude is the height of the water above the gauge. If the heating pipes are just above the ceiling then they are probably full of water. But not any or much in the expansion tank.

Most likely needs water added as the open system will lose water due to evaporation.

That gas valve lever should go from pilot to "set" and spring back to pilot.
The set position overrides the function of the thermocouple/safety, that is why you have to hold it until T-couple warms up......we assume the gas is on to the house.

The spring return must work or new valve needed.

leonz · October 2023

The saddle tank has a drop pipe to allow hot water to circulate which is good.

There should be a cool water return pipe in the basement right under the boiler and the near the basement wall as I believe the pipe in the rear which is a welded Tee feeds the cooler return water to the boiler sump.

You should have a plumber look at the burners, clean them and test the ignition system as the ignition system may be defective or there may be an electrical problem with the burner. when she kept it lit all the time there was little chance of having spider webs create havoc in the igniter and burner.

If the gauge does not work after tapping it, I would order an American made triple gauge from Dwyer instruments sized for the gauge tapping as I have had very bad luck with Chinese made gauges and I do not trust them.

So far so good.

JUGHNE · October 2023

Also, if pilot has been on for years at a time, it has happened that the Tcouple will not function.
But you have to get the pilot lite to find this out.

guzzinerd · October 2023

Thanks

She's calling the plumbers to get the pilot going .

leonz · October 2023

Hello guzzinerd,

I am glad to hear things are progressing for her sake,
I hope you can take more pictures of the basement piping soon.

That is a beautiful simple boiler that she has there and as it is
not leaking that is another plus for her.

guzzinerd · October 2023

Just an update. The igniter box had a "set" feature I needed to fiddle with before lighting the pilot.

Regarding the water level, you just turn on the water valve behind the unit and shut it off when you see water coming out of the 90-degree overflow pipe through roof above.

Pretty darn simple.

JUGHNE · October 2023

Was the "set feature" in another control or just the one on the gas valve.

In any event they must spring return when released.

tim smith · October 2023

I was surprised to see it even had a pilot safety on it under the burner cover. use to see the old valves with even a manual open lever. Ha, that was not such a great idea. That is as simple as it gets boiler. We just re worked some gravity piping for a house last week. Was not working well until we re routed a pipe and flushed the partly blocked underground return. Cool old beasts. She might want to have someone add a low water cutoff to the old beast.

tim smith · October 2023

top of that boiler makes a great bread warmer or even soup warmer.

JUGHNE · October 2023

That is a fairly "new" gas valve for standing pilots. I might have a couple on the shelf.
It probably replaced the original gas train of regulator-solenoid gas valve-with Basco ? safety switch but maybe a "live" pilot burner that was manual on or off. Gas would go up flue pipe upon pilot failure which would lock main gas valve out.

guzzinerd · October 2023

JUGHNE said:

Was the "set feature" in another control or just the one on the gas valve. In any event they must spring return when released.

Was in the same control, all the way to the right. If it had said "reset" instead I would have tried it first but had no idea what "set" meant so didn't touch it.

leonz · October 2023

YAY!!!!!!!!!!!!!!!!!!!!!,

I am glad she has heat and a reliable simple boiler that heats her home with low pressure water flow that is working again. Her system is heating her single story home with 160 degree hot water which saves her a lot of money.

The pressure gauge on her boiler is an original Charles Marsh triple guage.

guzzinerd · March 2024

So the woman who owns this wonderful old boiler called me about a leak in this system. It is dripping down the water feed from the supply tank so I went into her attic, unwrapped the tank and found a few weep holes. She doesn't have a LWCO so it's off until we fix it.

Questions to you guys are:

1.where to find a replacement tank?
2. Will this have to be made using a generic tank?
3. Can we use stainless?

Thanks

WMno57 · March 2024

Three ways to do this:
Open compression tank (what she has now)
Closed compression tank
Modern expansion tank (also called a diaphragm tank)
If it were my house, I would relocate the tank to the kitchen or basement.
Quality Tanks Inc in Clinton Wisconsin makes compression tanks. I have one and like it. They sell one that has fittings for a sight glass. You might be able to use the upper sight glass fitting for the roof outlet.
https://qualitytanksinc.com/4574-2/

JimP · March 2024

Wow. Very cool that this system has been kept intact all these years. Nice that you may be able to get a replacement tank.

Systems like this that I’ve come across have been modified. The expansion tank gets moved down to the basement or in this case maybe behind the boiler in the kitchen. If that’s done and other piping remains there needs to be an air bleeder in the attic above the riser. (Ive never come across an intact gravity flow bypass that keeps the water warm in the attic.)

I’ve found that the air bleeder is tricky. An automatic air vent will let air in if a vacuum develops up at the top. If that happens you’ll have no heat. I’ve seen a situation where a radiator froze in an empty apartment and did a lot of water damage to a building. I haven’t found a dependable air vent for a situation like this so you’ll need to work with the homeowner and find out what she’s comfortable doing.

If you put a vent in the attic it helps if the attic location is easily accessible and the homeowner is vigilant in being sure that the heat is always working especially when there’s a chance the pipes might freeze.

I’m curious if anyone has a foolproof way to vent the pipe if the tank is moved.

Good luck!

guzzinerd · March 2024

WMno57 said:

Three ways to do this: Open compression tank (what she has now) Closed compression tank Modern expansion tank (also called a diaphragm tank) If it were my house, I would relocate the tank to the kitchen or basement. Quality Tanks Inc in Clinton Wisconsin makes compression tanks. I have one and like it. They sell one that has fittings for a sight glass. You might be able to use the upper sight glass fitting for the roof outlet. https://qualitytanksinc.com/4574-2/

I like this solution a lot, thank you

JimP said:

Wow. Very cool that this system has been kept intact all these years. Nice that you may be able to get a replacement tank. Systems like this that I’ve come across have been modified. The expansion tank gets moved down to the basement or in this case maybe behind the boiler in the kitchen. If that’s done and other piping remains there needs to be an air bleeder in the attic above the riser. (Ive never come across an intact gravity flow bypass that keeps the water warm in the attic.) I’ve found that the air bleeder is tricky. An automatic air vent will let air in if a vacuum develops up at the top. If that happens you’ll have no heat. I’ve seen a situation where a radiator froze in an empty apartment and did a lot of water damage to a building. I haven’t found a dependable air vent for a situation like this so you’ll need to work with the homeowner and find out what she’s comfortable doing. If you put a vent in the attic it helps if the attic location is easily accessible and the homeowner is vigilant in being sure that the heat is always working especially when there’s a chance the pipes might freeze. I’m curious if anyone has a foolproof way to vent the pipe if the tank is moved. Good luck!

So much to consider. It has pretty easy access now, good headroom and close to the attic opening.

leonz · March 2024

Wessels tank company can provide you with a near identical galvanized "open to air horizontal expansion tank"/saddle tank for her heating system or steel expansion tank.

A horizontal steel compression tank fitted for an open to air expansion riser will not rust as quickly-if at all as a galvanized tank but it will cost more to buy but it will last much longer than a Galvanized tank.

She has the simplest of installations that can be replaced so obtaining a near identical tank will be no problem, do not let anyone convince her or you otherwise.

You may need a few more unions for the riser and the return/drop pipes and more pipe to re-assemble the vent pipe through the attic but that is a small issue in the scheme of things.

The installed the Open To Air Saddle Mounted Expansion Tank was placed in the attic first and then the piping from the open to air expansion tank was assembled and dropped to the boiler in the kitchen.

The riser and drop pipe are what is supporting the tank as there is no shelf used to set the tank on due to the roof design which has no trusses.

In order to preserve the plumbing as is you would need to do the following

1. drain the system and then dismantle the tank by cutting the tank apart first
2. then carefully cutting the galvanized steel away from the pipe fittings leaving the threaded parts
untouched
3. you would be able heat the tank parts attached to the existing piping then remove them and then clean
the threads.

As this beautiful heating system was built from the top down it will take patience to reassemble it to its previous state with a new tank.

What you need to do is take more pictures of the attic plumbing to enable you to order and purchase the correct tank with the proper dimensions and pipe tapping locations.

With any luck the paint identifying the tank is still intact and legible so you can go from there.

NOW You have the option of cutting of the open to atmosphere vent pipe off and then cutting the hot water riser pipe and the cool water return pipe off under the tank and then breaking the unions connecting the pipes to the piping below it and replacing all this pipe with 3 joints of black iron pipe with unions which may indeed be simpler to do as you can spend more time ordering the right tank for the system as the riser and drop pipes are the only things supporting the existing open to air expansion tank.

She has the opportunity to have an open to air expansion with an overflow tapping that can indicate the water level on the tank which would allow her to stop filling it when it is 2/3's full to allow for the water level in the saddle tank.

If not, she can keep the system as is with the vent pipe which has worked from the beginning which has less piping in the scheme of things.

NOW if the ceiling joists are intact and in good condition a support shelf/box for the new open to air expansion tank can be made from simple Douglas Fir lumber using the ceiling joists to support it and the drop pipe and riser pipe making sure there is a wide enough opening to allow the two pipes to pass through the box to allow the use of short nipples and unions to connect the tank to the new hot water riser and cool water return piping.

THE FIRST THINGS YOU NEED TO DO are measure the tank circumference and length to figure the volume,
then take pictures of the tank, the tank tapping's and measure the circumference of the pipe to enable you to order the right size pipe, short nipples and unions.

I have sent you a PM.

guzzinerd · November 2024

Ok. So finally found a suitable similarly sized, tank. Today I cut out the old one. Next, some map gas and cheater bars to see if I can't loosen up the old fittings. I know this is old hat for you guys, I'm going to post progress in case you notice I'm doing anything wrong or have suggestions ( thanks Leon!)

To avoid dealing with a million different black pipe reducers, angles, unions etc, the plan it to use npt male pex adapters to tie into the original risers and support the tank with straps coming from the roof timber.

(No one in our area will touch it)

guzzinerd · November 2024

Came right off!

delcrossv · November 2024

What size are those risers? 1-1/4?

pecmsg · November 2024

that system is old but the pipes do not look bad!

guzzinerd · November 2024

https://forum.heatinghelp.com/discussion/comment/1819712#Comment_1819712

2". I'll be installing a reducer to match the 1.25" openings on the tank

https://www.grainger.com/product/Reducing-Coupling-Red-Brass-1VGF6

guzzinerd · November 2024

Pretty much done now. The 1.25" pex i thought would be easy ended up being terrible to work with.

Flushed, filled and turned on the boiler for the first time this year. No leaks, all the rads are hot, yay.

Tomorrow I'll inspect for leaks one more time before insulating everything.

The old thermostat wires needed replacing as well 🔥

delcrossv · November 2024

Good for the next 100 years!

Well done, @guzzinerd!

Whose tank did you go with?

guzzinerd · November 2024

Thank you. Ended up with a 12 gallon quicktank, the original was around 10 gallons

Screenshot_20241124_191934_Samsung Notes.jpg

Steamhead · November 2024

That boiler is an "Arcola Parlor Heater" made by American Radiator Co. It was designed for this type of installation, and took the place of a radiator in the room where it was installed. First time I can remember seeing one still in use. Where is this job located?