Water Loss

Jeremy_16

I recently had a conversation with a property manager about installing water meters on steam boilers with automatic water feeders in order to detect if the automatic water feeder is adding too much feed water (like if there is ever a leak in an underground wet return or a hole in the boiler, etc)



He insisted that installing the meter doesn't need to be done because he has a chemical company that monitors the PH level of the boiler and they would know if there were an issue. He said that they come out once a month to test the boiler water.



I don't know how a company measuring the PH level would know if there was too much feed water being added because I assume in some areas the feed water is the same or similar PH as the water in the boiler (we are in Boston). Maybe the company adds a chemical or something and monitors the presence of that chemical. I have no idea though.



Does anybody have any insight about this? Is the property manager wrong? I thought I read from one of Dan Holohan's articles that the only way to tell if you are taking on too much feed water is to meter it: <a href="http://www.heatinghelp.com/article/323/Boilers/244/Steam-Boiler-Failure">http://www.heatinghelp.com/article/323/Boilers/244/Steam-Boiler-Failure</a> (see 3rd paragraph from bottom). Does that hold true in this case?

nicholas bonham-carter

better boiling through chemistry????

I would say the property manager is wrong. the chemical brothers attending the boiler will have no idea why the water pH has changed.

in the absence of a water meter, then the auto feed could be valved off, and the waterline checked for change after 24 hours.

some people love additives, in food, in car fuels/lubricants, and even themselves.

a standard cast iron boiler will only need additives in order to correct a specific water condition. additives can change the steam to wet, and increase the running cost of a boiler.--NBC

Jamie Hall

I suspect the chemical folks

may have come up with an interesting way to add to their bill.



However...



If there is a definable, conservative trace element in the feed water and

if the concentration of that trace element is known and known to be constant in the feed water and

if there are no chemical reactions involving that specific element and

if that element does not evaporate or get carried out by wet steam and

if you measure the change in concentration in that element with time

you can, in principle, detect and measure a steam leak.  You can't detect or measure a condensate or boiler leak.



And I wouldn't be on it, anyway.

Charlie from wmass

SO how good of a Christmas gift

does the building manager get from the chemical company. Meters are used because they give a record of gallons or cubic feet of water that can be used to either confirm or deny your warranty claim if your block fails. Also you find out how much water the boiler feed pumps are over flowing during a cycle and dumping down the drain.

Jeremy_16

Water Meters and PH testing

Thanks for all of the responses.



I assume that you each would recommend water meters for all steam boilers with automatic water feeders then, right? I really want the manager to install one because it's a minor cost and provides vital information about the amount of fresh water being added.



The manager said that right now the chemical company comes once per month to monitor the PH level. If there aren't any issues with the local water, is this even a necessary expense to incur monthly? I imagine testing it annually or even biannually may be worth it, but monthly seems a bit overkill... What do you think?



Thanks again!



-Jeremy

nicholas bonham-carter

make up water metering

how big is the boiler?

valve off the auto feed, and see if there is any drop in the waterline over a few days.--nbc

Jeremy_16

No Leak Now

The boiler is for a condo building with 14 units that is 4 stories tall. Not sure of exact size...



We aren't worried about a leak presently, but I worry that if there is no meter we would never really know about a potential leak in the future (unless that chemical company has some kind of magic chemical we don't know about or the leak got bad enough)



In some other buildings we are involved with, the water meters are checked weekly when the low water cut off is flushed. The readings don't usually change very much week to week. But if they did, it would signal a potential problem/leak.



We own a condo unit in another building that recently lost a steam boiler due to holes near the water line. There was no water meter on that boiler... That's what really got me thinking about making sure water meters are installed on all steam boilers with auto water feeders. I don't know for sure if a leak in an underground return caused the auto water feeder to fill the boiler with too much fresh water over time, or if the boiler just failed prematurely due to other manufacturing issues, etc. But I figure it's better to install the water meter and be safe rather than sorry, right?

Charlie from wmass

The simple answer

replace the water feeder with a VXT 120 or VXT 24 depending on application as it has a built in meter.

Hap_Hazzard

pH won't necessarily change

A better test would be hardness or specific gravity, but this assumes minerals aren't already at their saturation points at 212°F, and I wouldn't assume that. In my experience, and the experience of a lot of the pros who post here, most tap water forms scale in boilers. In other words, minerals come out of solution at boiling. So the addition of makeup water to replace lost steam or condensate wouldn't produce higher solute concentrations; it would just produce more precipitate. One of the pros here once described the effect over time as being like pouring concrete into the boiler. That sounds pretty accurate. You would sooner notice a change in volume than a change in water chemistry, but by then you'd need a new boiler.

Jeremy_16

water meter

Sounds good to me, but I don't think they will want to replace the water auto feeder (I can suggest it though). Do you always put in some kind of water meter on your new jobs? I basically just want to know if this is standard practice and something is missing here.

Jeremy_16

Clarification Question

Are you saying the pH won't necessarily change with the addition of more water through the water feeder? I didn't think it really would either if that's what you're saying. I just thought that with more water being added, we would have more oxygen which would lead to more corrosion over time. Since the pH wouldn't change, then we wouldn't know about this water being added until it was too late. Right?

Jamie Hall

Right...

on all counts.  Which is why you should have a water meter.  I like Charles' suggestion -- it's simple and reliable.