Steam Boiler Water Feeder Valve Q&A #2

Recent FAQs on how to diagnose & fix a water feeder valve

Diagnose & Repair Error Message or Flashing Indicator at Automatic Water Feeder

Automatic water feed keeps coming on and green light flashes and red Manual Reset light flashes

After turning up the heat, I waited for the furnace to reach temperature, and turned down the thermostat.

The auto water feed came on, even though the return condensate more than filled the furnace. I drained it down to a proper level, and the auto feed came on again.

Also, the green light on the feed control is flashing, and so is the red "manual reset" light. Any suggestions? Oh, and the pilot stays on, as well. (Dec 18, 2014) Tom said:Hi.

Reply:

Tom do you think the auto water feeder is not properly sensing boiler water level? Debris clogging can be a cause.

Check the water level in the boiler sight glass.

Meaning of flashing at the automatic water feeder control

Auto Feeder Box is flashing, I don't think that it is working, should I be concerned? On 2017-08-27 by Marie

by (mod) - some red light flashing may be normal - check the water level in the boiler

You have to keep adequate water in the boiler to protect it from being damaged.

But some water feed controls have a red light that flashes (next to the digital readout display) simply meaning that the automatic water feeder is in the process of adding water to the boiler. That would be normal operation and not a problem.

But

Watch out: if the light never stops flashing then yes, something's probably wrong and you need to call for repair. (We're forced to guess here since we don't know which automatic water feeder brand and model you have installed.)

First check the water level to be sure it is at the proper line marked behind the sight glass. If the water is below the safe level it would be best to turn off the boiler. In any case you need to call for repair.

Watch out: if by "Feeder Box is Flashing" you mean that the digital counter on a Hydrdolevel VXT type water feeder is flashing, that means that the meter has “rolled over” (exceeded 999) representing an excessive feed amount for most applications.

Here is what Hydrolevel says:

If the digital counter is flashing, the meter has “rolled over” (exceeded 999) representing an excessive feed amount for most applications.

Check the system thoroughly for leaks. If no leaks are found, check to determine if the make-up waterline is restricted. Check feed valve strainer for blockage or heavy build-up of debris.

Reset Feed Counter (see above) once problem is resolved.

See details at

• Hydrolevel VXT-24 PROGRAMMABLE WATER FEEDER for STEAM BOILERS MANUAL & ERROR CODES [PDF] (2019) 24VAC operating voltage
• Hydrolevel VXT-24 PROGRAMMABLE WATER FEEDER for STEAM BOILER INSTALLATION INSTRUCTIONS (2021) [PDF] (2021)

What Causes of Error Messages at Steam Boiler Controls

What causes an error maessage on a steam boiler water feeder? (Nov 4, 2015) ishkhan

Reply: examples of steam boiler water feeder error messages and what causes them

Error messages are device dependent. Tell us the control or brand and model and we'll help you find the manual and its troubleshooting section that will decode error messages.

As just EXAMPLES of water feeder error messages (since we don't know what steam boiler water feeder or other control you have), on a Hydrolevel VXT-24 water feeder used on many steam boilers,

• A small indicator light in the lower right hand corner of the feed counter that is "on" means that there is a call for water.
• LOC displayed in the digital counter on the water feeder means that the control is on Safety Lockout following tow successive water feed cycles
• Err in the digital counter on this water feeder means that the control is not set properly

These are just examples and are not a complete explanation. The details will be in the IO manual for your boiler water feeder.

To find the manual for your specific steam boiler water feeder and thus to read its error codes

see

• STEAM BOILER WATER FEEDER VALVE MANUALS

For a nice EXAMPLE of steam boiler water feeder error messages and what they mean, see this manual:

• Hydrolevel VXT-24 PROGRAMMABLE WATER FEEDER for STEAM BOILERS MANUAL & ERROR CODES [PDF] (2019) 24VAC operating voltage

Watch out: If you are in the slightest doubt about the safe normal operation of your boiler, turn off your heating system and call for repair as there are life safety hazards involved.

Daniel Friedman

What does "h00" mean on my water feeder? Understanding water feeder water usage readout.

I just got a new boiler. The automaic water feeder used to read 200 a week later reads h00. What's that means? (Dec 9, 2015) Anonymous

Reply: Water feeder is in standby mode

Without knowing the specific brand and model water feeder on your steam boiler I don't know for sure, but

typically a display of h00 on the water feeder means it's in standby mode.There is no call for heat at the boiler.

What to do in response to a water feeder code h00:

Turn up your room thermostat and confirm that the steam boiler runs. Once the steam boiler has used some water the water feeder should automatically feed water into the boiler and the h00 reading will change to a water feeder amount.

What is the meaning of a blinking red light on my steam boiler water feeder display?

Why does my LED Programmable Water Feeder light blinking? (Jan 1, 2016) Anonymous

Reply: a boiler water feed cycle is in progress

On some water feeders such as the Hydrolevel VXT series, a small red light at the corner of the LED display window blinks when the control is in process of feeding water into the steam boiler. That's a normal condition.

We need to know the water feeder brand and model to find an exact answer to what various lights, colors, and blinks mean on your specific device.

- that information is in the installation/operation manualf or the water feeder. If you don't have that information we can help you find a manual but we need to know what equipment we're researching.

The orange "fill" light keeps going on at my Water Feeder Valve

When I check on my boiler in the morning before the heat even starts for the first time, I notice the orange "fill light" is on. It then clicks off and the green light on the sensor on the filler pipe blinks on and off for about 10 seconds then it shuts off and the orange "fill light" (the one on the boiler) goes on again.

This cycle just seems to keep repeating. The water level in the boiler is fine and the sight glass is about 1/2 full. Is this normal? I'm not sure if this is some sort of recalibration process or preheating or what...Thank you for any comments....

Regarding my comment "When I check on my boiler in the morning before the heat even starts for the first time, I notice the orange "fill light" is on.

It then clicks off and the green light on the sensor on the filler pipe blinks on and off for about 10 seconds then it shuts off and the orange "fill light" (the one on the boiler) goes on again.

This cycle just seems to keep repeating. The water level in the boiler is fine and the sight glass is about 1/2 full.

Is this normal? I'm not sure if this is some sort of recalibration process or preheating or what...Thank you for any comments.... " - I should have also noted that the water does not actually turn on - it just keeps going through this light cycling process. Also, when I come home after work, all seems fine.

I had plumbers look at it and they found nothing which made me think this is a normal "early morning" process that I never noticed before. On 2017-02-01 by Anonymous -

Moderator reply

It's normal for the small "fill" light to be on during the time that your automatic water feeder valve is sending water into the steam boiler.

Only if the light never goes off would I be starting troubleshooting and watching for a flooded boiler.

You can confirm that your boiler is Okay by checking the water fill level in the sight glass against the mark on the boiler showing the target fill level.

Steam Boiler Not Getting Enough Water Q&A

Steam Boiler Automatic Water Feeder does not automatically refill

I have a Mcdonald Miller control on a small steam boiler - the low water cut off works but it will not automatically refill as the water level drops.

Is this a float valve problem or is it electronic? - the MM sn is 204835 - the MM control is N'47-2, 2 switch model 2 - On 2017-10-09 by William McCrea -

Causes and cures for steam boiler not getting enough water

William

The McDonnell Miller Series 47-2/247-2 Mechanical Water Feeder/LWCO is a mechanical (not electronic) control that uses a moving float arm to sense water level.

I look first for a debris-clog that is jamming a float. The following diagnostics are quoted from the I&O Manual for this control, available from

McDonnell & Miller and also as a free download at our article LOW WATER CUTOFF VALVE
at https://inspectapedia.com/heat/Steam-Boiler-Control-Manuals.php

Boiler is not getting enough water.

a) Cause: There is something preventing the valve (cartridge poppet) from fully opening.

Test: Perform broken union test.

Solution: Remove and inspect cartridge. Clean or replace as necessary.

b) Cause: Strainer clogged with sediment.

Test: Perform broken union test.

Solution: Remove and inspect strainer. Clean or replace as necessary.

c) Cause: Float chamber clogged with sediment.

Test: Open blow-down valve. If there is little or no water flow, the chamber may be clogged with sediment.

Solution: Remove bottom of float chamber and clean sediment from chamber, float and bellows mechanism. Replace control if necessary.

d) Cause: Feed line between valve and boiler is partially plugged.

Test: Perform broken union test. With union broken, there should be water flowing through the piping from the boiler.

Solution: Clean or replace piping. e) Cause: Feed line between valve and city water supply is plugged. Solution: Clean or replace piping.

f) Cause: Water supply pressure is less than boiler pressure.

Solution: Reduce boiler pressure or convert to pumped return.

No water flows into the steam boiler when the electric water feeder is on

When water gets low in my steam boiler, I can hear my McDonnell Miller Auto-Feeder turn on, the green light glows, but water doesn't flow through to the boiler.

I've cleaned the filter/screen at the hex plug below the feeder, but it wasn't dirty at all. The water valves at either side of the feeder are open and water flows fine when the hex nut is open. It's just that no water flows when the electric feeder turns on.

Any suggestions for simple maintenance or repair, or am I stuck with replacing the whole feeder unit? (Jan 31, 2015) Sean F.

Reply:

Sean

Temporarily you'll have to use the bypass valve and piping to keep water in the boiler. It should be possible to clean the water feed valve - see notes in the company's installation and service manual for your unit. Or if you don't have one, give me the model number and serial number and I'll help you look for one.

Or your service tech can install what you need faster and easier than a DIY project.

Sean F.

I have the manual. I just need to dig it out, and find the cleaning details. I wasn't sure if that was user serviceable. Thanks for the tip.

Does the automatic water feeder add enough makeup water to a steam boiler & Should I add water manually?

Does the automatic water feeder on the steam boiler add water slowly to the boiler and if you have to add water manually should you add slowly when the boiler is not running. - Mary Jo Barranco

Reply:

Mary Jo:

If your steam boiler has an automatic water feeder it will add water whenever the level drops enough to drop the float in the sensor. It doesn't feed water continuously.

The water feeder will add water frequently enough, and in small enough doses, and at a slow enough rate that even if the boiler is hot the makeup water won't damage the equipment.

You can take a look at the water level in the boiler by noting the sight gauge - that vertical glass tube.

There may already be a normal water level mark - if not, just put one on with a magic marker.

Watch out: If you should see the water level in the boiler fall say half way between that mark and the bottom of the sight glass, then I suspect the auto water feeder isn't. Otherwise it should come on by itself and restore water to the boiler as needed.

and

Watch out: Yes, IF you had to feed water to a heating boiler manually, it's safest to do so either when the boiler is cool or cold (that's best) or very slowly if the boiler is hot. Otherwise the risk, especially with a cast iron boiler, is serious damage such as cracking a boiler section due to thermal shock.

How to diagnose frequent on-cycling of automatic water feeder on boiler; initial dwell? dip switch settings?

My new steam boiler has an auto feeder that cycles on frequently, even when the boiler has been off for hours, such as overnight. Is that normal? I am considering changing the DIP switches to change the dwell/feed but need your advice. Can you tell me if increasing the feed time would add more time between cycles?

What does "initial dwell" refer to? There is no marker on the sight glass but the water generally lays at one third the twelve inch glass. I think that is low but even if I add water manually, that level is maintained after a while. - Bob Q from Brooklyn

Reply: look for a leak in the steam piping, particularly the condensate piping, or possibly improperly functioning steam vents

Bob Q,

When a steam boiler is and has been cold for a while no water should be leaving the boiler, and therefore I wouldn't expect the auto water feeder to cycle on. Even though your steam boiler is new, it's likely that your steam piping, condensate return lines, etc. are not. I'd look for a leak around the boiler itself.

You can miss a small boiler piping leak when the pipes are hot because the leaking water just evaporates. Check carefully when the system has been cold and off for a few hours or more.

I understand the temptation to adjust the automatic water feeder, but those adjustments wouldn't be expected to make the device feed water when the system has been off and cold.

When you feed extra water to the boiler it will eventually be consumed (steam losses in the system - all steam systems consume some water) and since you fed it manually, the system will naturally return to the water level being maintained by the automatic water feeder.

About whether or not the set level of water is too low, look on the boiler itself - many of them have a "water level" line marked or riveted on the boiler side by the manufacturer.

If you send me (use the CONTACT link on our pages) the brand and model of your water feeder I'll dig up the instructions to see what further advice we can offer.

TP keeps dumping water, have to keep refilling the steam boiler

I have Burnham steam system by gas. Recently a valve which 3/4 inch fitted on the top of black nipple and nipple is screwed to 3" pipe.

This 3" pipe is coming from the H system, vertically about at 4feet and bends at 90 degree. Right at this bend is the valve attached to the pipe and the valve.

This valve is constantly blowing steam whenever the heat is called for by the thermostat and water has to be added once or twice or three times a day. I have not seen any other water leak or steam leak from the radiator valves. What is your feed back? This is Archie (Jan 30, 2014) Archie

Reply:

Hi Archie,

I'd like to see a photo of the piping and the valve you discuss - I'm not sure what we're talking about. If there is a label on the valve tell me what it says; Or use the CONTACT link at page bottom or top to send me some sharp photos.

Watch out: The system is unsafe: You may be seeing a pressure relief valve blowing, or it may be a steam vent; I can't tell, but it sounds as if one of these is stuck open. (Or is doing its job because the system is not working properly).

Water level drops too Low on Williamson steam boiler

I have a Williamson boiler just installed but the water level continues to go below level and I have to manually feed the water into the boiler.

Left house for 2 hrs came back and house was only 58 and theremin stat was set at 68, boiler turned off and had to manually add water again.

Not sure why boiler isn't holding the water . (Nov 29, 2014) Ryan

Reply:

Ryan,

Water loss at very high rate from a steam boiler suggests that there is a leak somewhere, most likeley in a condensate return line.

I'd also check every radiator in the system for signs of condensate leakage.

A second possibility is that a condensate return line is blocked and water is just not returning to the boiler.

Automatic Water Feeder Installation & Wiring

Should I put an automatic water feeder on my boiler?

My boiler died and I need to replace it. I chose a Burman boiler. I have steam heat operated by oil. I wanted to put in an automatic water feeder but I am having second & third thoughts about it.

I have read where it can cause flooding both upstairs and downstairs and 2 plumbers did not recommend the automatic water feeder.

Any thouighhts or help? On 2018-02-13 by Judy - S

by (mod) -An automatic water feeder saves you trouble and increases the reliability of your heating system.

Judy

An automatic water feeder saves you trouble and increases the reliability of your heating system. There are several residential steam boiler water feeders and level controllers. CHeck the requirements for periodic manual cleaning (flushing of the water feeder) as that may vary among designs.

Please ask your plumbers to be very specific about why they recommend against an automatic water feeder on a residential steam boiler. I'd like to learn from their experience and to report that to others.

Their argument might be that it's better to force the homeowner to make a regular inspection of conditions at the boiler, or they may have had a problem with improperly-installed or improperly-maintained controls that flooded the steam boiler (there are excellent devices designed to prevent boiler flooding)

However a problem with boiler flooding ends at the same place (loss of heat) as a steam boiler into which the homeowner forgets to manually add water when needed (possibly daily during very cold weather) and also the same as a boiler whose low-water cutoff (LWCO) safety device is not maintained by the homeowner (regular flushing) - also leading to loss of heat or worse, a damaged boiler.

If you're worried about boiler flooding or boiler running out of water regardless, there are reliable add-on devices that sense and protect against that- discussed in the article above on this page.

But I would certainly use a plumber who has had successful water feeder installations to do the job. I worry that a contractor who condemns such as common and widely used heating system control may have had bad experience not because the control is defective but because she has repeatedly not followed the proper installation or maintenance instructions given by the manufacturer.

On a rainy day I inspected a new home whose gutters were all spilling over, pouring water along the house foundation.

The builder was there.
I asked him if he'd noticed that none of the guitters were working and all were spilling over instead of conducting roof drainage away from the building.

"Yeah," he said, "That's normal. They all do that".

On a closer look I saw that the roof edge flashing was improperly installed, directing roof runoff behind the gutters rather than into them.

So yeah, all of the gutters that HE installs do spill where they shouldn't.

No one will say if the water feeder connects to cold or hot water supply

Not one of these companies not one of them tell you whether the automatic water feed is connected to the cold or hot water now one company tells you in writing .

The water pipe in the PDF is labeled water supply . After your house floods and your insurance adjuster comes out and tells you it can’t be connected to the hot water you realize why . Why don’t they sat which water supply it belongs connected to ? On 2017-12-31 by Steve

Reply by (mod) -

Steve

Companies making boiler water feeders assume that their equipment is being installed by a plumber or heating technician and they assume the tech knows to connect the boiler feed water to the building's cold water supply.

But your are mistaken in assuming that the manufacturers do not specify how the water feeder should be connected.

In the live links above you will find this example

McDonnell & Miller ITT Series 47 & 247 Mechanical Water Feeders, Series 47-2 & 247-2 Combination Mechanical Water Feeder & Low Water Cut-Off

wherein the company tells us in bold font right at the top of the installation instructions:

Application:

For steam and hot water boilers with cold water feed, to maintain a minimum safe water level independent of electrical service.

I agree that it is difficult for a manufacturer to anticipate all possible snafus involving their equipment. But in this case those instructions are clear.

For other readers:

Watch out: NEVER connect a heating boiler's water supply from the building hot water piping.

All of the boiler controls, such as automatic water feeders assume a cold water feed. That's because feeding in hot water starts the boiler at a higher temperature that in turn risks over-pressure conditions and leaks at a relief valve when the boiler's burner operates.

Warning if using an electronic automatic water feeder with the McDonnell Douglas Series 700 LWCO manual-reset model

I just bought a McDonnell Douglas series 800 probe low water cut off manual reset model and it says do not use with electronic automatic water feeder's do you know why On 2017-02-18 by Sam

by (mod) - beware of over-filling your steam boiler

Sam, that's a good question.

McDonnell Douglas says

Watch out: using an electronic automagic water feeder with a McDonnell Douglas Series 700 LWCO manual-reset model can lead to flooding of the steam boiler - that is, the water feeder may over-fill the boiler.

See this ITT McDonnell Miller LWCO manual for details

Install a VXT-24 auto water feeder on a residential millivolt steam boiler?

Is it possible to install a VXT-24 auto water feeder on a residential millivolt steam boiler?

The millivolt steam boiler has no incoming power source connection because the burner and controls circuit is 750 millivolts (less than 1 volt) and is powered by the power pile generator above the pilot light.

If the boiler goes into emergency low water cut-off, the millivolt circuit does not have enough power to operate and open the water feed solenoid valve on the VXT-24 because that valve needs 24 volts to operate.

Is there a type of relay control available the receives the millivolt low water signal and converts it to 24 volts to operate the feeder? On 2018-02-08 by jerry thibault

Reply by (mod) -

Jerry

I think that's quite possible provided that you install a suitable power transformer as needed to power the 24VAC VXT. Before buying the water feeder give Hydrolevel a call and ask for hookup advice 800-654-0768

How do I know if I have a 120V Solenoid or 24V Solenoid?

How do I know if I have a 120V Solenoid or 24V Solenoid? - Evan.Penalba

Reply: check device labels, installation instructions, or wire diameters

Evan, take a look at the information labeling on your water feeder or other device: the operating voltage will be shown. If the label has become lost you'll want to take a look at wiring and installation instructions for the device.

If you don't have the installation and wiring manual for the device you (or we for you) can find that information from the manufacturer if you can identify the brand, model, or other information for the water feeder or other device.

Finally, if the device is already installed and wired, just take a look at all of the wires entering the water feeder. 24V electrical wires are typically very small in diameter

- typically 18-20 gauge while 120V electrical wiring will be the size of normal building electrical wiring - typically #14 or #12 copper wire. You can see photos and tables of electrical wire sizes and diameters

at SE CABLE & BRANCH CIRCUIT WIRE SIZES vs AMPS .

What voltage does my automatic water feeder use?

How do I know what voltage my auto feeder control needs? On 2018-11-16 by Jesse

by (mod) -

Voltage is given on the device data tag, typically your boiler controls in the U.S. or Canada run on 120VAC but in other countries the control may be designed for 240VAC or 120VAC or 24VAC

Can a 120 volt auto feed work on a 24 volt low water cut off?

Can a 120 volt auto feed work on a 24 volt low water cut off ? On 2017-12-29 by robert

by (mod) - never direct 120 volts to control that's only rated to handle 24 volts.

Watch out: You should never wire 120 volts to control that's only rated to handle 24 volts. That would be dangerous.

But it is certainly possible that to separate controls, one operating at 24 volts and another at 120 volts, and performing different functions, would be found on an individual heating system.

Or your installer may use a switching relay that uses low voltage to switch a 120VAC control on or off.

Water Feeder Adjustments or Settings

Is there a way to adjust the level on the water feed to keep it in the middle?

My boiler water level has just started raising and the whole system is knocking, etc. I flushed out the system and refilled the boiler but it keeps going way past the usual spot about half way up the glass display on the side to about the top of the display.

Is there a way to adjust the level on the water feed to keep it in the middle?

I figure something must have broke since this just started happening along with excessive steam from the radiators. thank you On 2017-01-13 by Chris - I

by (mod) - fix or replace the automatic water feeder

This sounds to me as if your steam boiler's automatic water-feeder control is either out of proper setting or adjustment, or the valve is not working correctly and needs repair or replacement.

Best would be to get your experienced steam heat service technican on site to be sure your water feeder is working properly and to show you its adjustment settings.

Is it normal to have to add water to a steam heating boiler when it is very cold outside?

Is it normal to have to add water to the water tube [sic - she means sight glass] on furnace [sic - she means boiler] when it is very cold out ? On 2017-01-10 by Joan

by (mod) - yes

Joan:

In a sense, yes.

It is normal for steam heating boilers to consume some water at each heating cycle. That's because even in a steam heating system in perfect operating condition, some water is lost in the form of steam at steam vents at each radiator at the start of each heating cycle.

Rising steam pushes out air in cold radiators, forcing the air out through a thermostatically operated steam vent on each radiator. At the end of that "force the air out" portion of the heating cycle a bit of steam escapes along with escaping steam before the steam vent closes.

And some steam heat systems whose steam vents are not working perfectly may continue to let steam (and thus water) escape longer into or even all during the heating cycle.

So in sum, part 1, all steam heat systems use some water each time the system goes through a heat-on cycle.

Now in cold weather a steam boiler will run more often, as the house is losing heat faster, so it needs more heat from the steam heating system.

When steam heat runs more often, more water is consumed or "lost".

When more water is lost, make-up water will have to be added to the steam boiler more-often.

You are not adding water just to the "water tube" (see SIGHT GLASS, STEAM BOILER)

You are adding water to the steam boiler itself.

If your steam boiler has an automatic water feeder valve it will do this for you.

If your steam boiler's automatic water feed valve is not working it's time to call for service and repair. Failing to do so can damage the steam boiler.

Watch out: also in times of frequent on-off cycling of the steam boiler its low water cutoff valve, a critical safety device, will need to be flushed or cleaned more-often.

See LOW WATER CUTOFF VALVE, BOILER