Stuck autofill valve

NathanHale

Hello All! Hope all is well with you all.
I have a Burnham steam heating system for my upstairs.

The electric autofill valve ( I am pretty sure that is what it is called), is stuck open. It is in the closed position in the picture below.
When I turn on the power to the entire system, the red button pulls itself down and stays there and makes a whining noise.

My problem is though:

a) When the red button is stuck open , I dont hear water going into the boiler. Do you know why there is no water going into the boiler even when the red button is all the way down?

b) The main question for you guys is: Assuming, there is an issue with the autofill valve, can I somehow override it, so that the boiler will fill with water and there will be heat atleast. I have no problem manually filling the boiler with water.

Thank you
Nathan

JUGHNE

Is that a series 101-A Mcdonnell & Miller?
Have only seen one in the book.
Some separate device sends a signal to this to activate an electric solenoid.
Either a float somewhere or an electronic probe.
You could Google for details.

Looks like it has been there awhile.
The bottom plate opens to clean the strainer.
The valve inside may be stuck.
The manual feed button on top should pass water.
Do you have another manual bypass valve to feed water?

ScottSecor

As JUGHNE suggested, the red button drops down when the solenoid opens (this is a result of the low water cutoff calling for more water). If no water is passing through the feeder that would indicate the feeder is clogged (or damaged). I'm guessing yours is clogged. Similar to another recent post on the wall, ("47-2") I suspect there is a leak in your heating system that has not been addressed and this contributed to the failure of your feeder. It could also just be past it's useful life.

Most boilers also have a another way to add water with a bypass valve. This is likely connected to the same source of water that is connected to the automatic feeder. Might want to hire a heating specialist in your area and have them go over the system and show you how to do some basic maintenance yourself.

Fred

Ditto what @ScottSecor said. The Low water cut-off is calling for water and the Auto water feeder strained is clogged and not letting water pass through to the boiler. You will likely need a new strainer and a gasket. The strainer is probably clogged beyond cleaning.

JUGHNE

If you look at the "47-2" posting you can see what happens if plugged.
In the little window on the upper right side of the filler there is some linkage that might be operated manually with a screw driver blade by prying up or down....just a temp fix.
The strainer is probably beyond cleaning as Fred says.
You could remove it temporally and see what happens.

SeanBeans

@JUGHNE i just installed one of those a few weeks ago on a new install, supply house must’ve been unsure of what I meant by ‘electronic water feed’

Although they did give me what I asked for

NathanHale

JUGHNE said:

Is that a series 101-A Mcdonnell & Miller?
Have only seen one in the book.
Some separate device sends a signal to this to activate an electric solenoid.
Either a float somewhere or an electronic probe.
You could Google for details.

Looks like it has been there awhile.
The bottom plate opens to clean the strainer.
The valve inside may be stuck.
The manual feed button on top should pass water.
Do you have another manual bypass valve to feed water?

Thank you for your reply. Here is the info plate picture.

Fred

On the bottom of that unit there is a flat plate with 4 screws in it (1 at each corner. The water supply has to be turned off, take those four screws out and inside there is a screen. I doubt that it can be cleaned but you can try. I would order a new screen and gasket before I took it apart. You will need a new gasket anyway. I think you can order the screen and gasket from supplyhouse.com . If not, just google McDonnell Miller 101A parts and several sources will pop up.

JUGHNE

From what SeanBeans noted, they are still used.
It is not as ancient as I thought. The hex head screws might indicate only 20 years old, possibly. The strainer assembly looks like a standard part. It will work temporarily without the screen installed in it.

That is what is great about the Wall, see something different every day.....for me anyway.

Please let us know of your progress.

ScottSecor

Just a reminder that I was taught a long time ago (probably by Dan Holohan) is to make sure the the feeder is piped into cold water. Same is true for all of the automatic feeders we've ever installed (electric and electronic).

NathanHale

Fred said:

On the bottom of that unit there is a flat plate with 4 screws in it (1 at each corner. The water supply has to be turned off, take those four screws out and inside there is a screen. I doubt that it can be cleaned but you can try. I would order a new screen and gasket before I took it apart. You will need a new gasket anyway. I think you can order the screen and gasket from supplyhouse.com . If not, just google McDonnell Miller 101A parts and several sources will pop up.

Thank you for your reply. I opened the 4 screws on the bottom ( indicated by the 3 blue arrows in one of the pictures below). I was able to gently pull out the strainer. The picture below shows the strainer. I washed it gently in super hot water. Then I scraped the iron oxide / rust looking stuff, gently with my finger nails. Seemed like the iron oxide/ rust looking stuff was only on the -outside- of the strainer and -not- on the inside.

Here is where it gets interesting. I went ahead and removed the 4 Allen socket screws ( shown with the 2 red arrows in one of the pictures below.) Later, I removed the cartridge ( The cartridge's picture is below and is labeled as exhibit A).

So, after removing the cartridge ( I think that is what it is called), I noticed some holes in it and I went ahead and gently , delicately cleaned the holes with a thin needle. Both holes were completely clogged by some kind of black material.
I put everything back, gently, carefully, delicately and turned the water back to the auto fill valve, and lo and behold, the water started to fill the boiler even when the red button is not pushed down.
I filled the boiler and manually turned off the water to the auto fill valve. The house is heating normally.
I think I might have replaced the cartridge 90 degrees away from the correct position. I did make an effort to look for marks that might indicate the cartridge position, but didn't find any.
i will go back and turn the cartridge around and see if everything works as it is supposed to.

Thank you all very very much for your valuable inputs.

JUGHNE

This looks like the set up on many MM fill devices.
Once you pull the strainer out you might have access to the water fill cartridge with a socket on an extension.
IIRC, once that is clean it should rattle when shaken.

Glad you are back in heat!

Fred

Yes, I think you put the cartridge in incorrectly. Once you turn it around, it should be fine.