Got my new VXT water feeder! How significant is this water loss?

bipbap

So after all the good advice I got here, about 2 months ago I replaced a failing water feeder with a VXT and can finally see real data on make-up water. I tracked it and here's what I recorded, I just don't know how good or bad these numbers are and am wondering if this is normal or if I should be doing something to reduce the water loss, even though there are no leaks or drips anywhere obvious, though some air vents might be old.

Feb 5: 10 (was at 10 when plumber finished installing)
Feb 7: 11
Feb 14: 11
Feb 16: 12
Feb 19: 13
Feb 21: 15
Mar 1: 16
Mar 5: 17
Mar 14: 19
Mar 28: 20
Mar 29: 21
Mar 31: 21

I didn't add any water or flush out any dirty water in the past 2 months, so it fed itself 11 gallons in about 2 months. That sounds like a lot (?) but we do have a large boiler and it has been cold in NYC in that time. This is a small multifamily with single pipe gas steam.

Boiler model was asked for last time I posted and it's a Weil-McLain EGH-105-PIN and it says gross output is 360k BTU, input 450K BTU if that is helpful.

Thanks in advance for your thoughts!

bipbap

Here are the full boiler details, attached photo.

Steamhead

That's more than it should be. Look for leaks- check vents and valve packing nuts.

bipbap

Could vents that don't close really be responsible for all that water loss?
I never see any signs of drip or water under or around valves.

AdmiralYoda

@bipbap I had a leak between two sections of radiator for YEARS. It didn't drip, it just had a barely there slight "hiss" and I didn't think anything of it. I was adding water manually weekly, probably a half a sight glass worth in the coldest months. Probably similar water usage as you...but with a boiler less than half the size.

I was convinced my boiler was leaking steam up the chimney. I fixed the radiator by removing the bad section and now I only add water once per month. I could probably get by with less than that but I drain a little out of the float type LWCO and bottom of the boiler every now and then.

I would say a leaky vent or trap or anything can lose quite a bit of water.

EdTheHeaterMan

Vents that don't close when steam reaches them should be replaced. Although it takes about 1700 times the volume of steam to vent for each gallon of water, but those vents can do a lot of venting. Is there higher than normal humidity in the home?

I installed an attic duct system for central AC, in a steam heated home. Worked great. The first winter, the ducts filled with water and overflowed into the rooms via the ceiling registers. High humidity and the cold attic allowed for the accumulation of "mucha condensación". (my son is getting married today, in Mexico)

I was lucky to be a little bit familiar with steam and decided to replace all the radiator vents. Also the customer elected the High Efficiency option which included the ECM fan on the air handler. Set the fan ot run @ 20% the rest of the winter and the condensation evaporated in time for the next summer. A few small sections of flex duct replaced and everything was just fine.

bipbap

No I haven’t noticed any high humidity.
Congrats on the wedding though!

Jamie Hall

bipbap said:

Could vents that don't close really be responsible for all that water loss?
I never see any signs of drip or water under or around valves.

Between vents that don't quite close and a few leaking packings on valves -- oh yes. And you'd likely never see it, not notice high humidity. Keep in mind the rule of thumb: a single little drip, every ten seconds, is a gallon per day.

bipbap

Ok thanks all.

So is the consensus that about 5 gallons per month is too much water loss on a system like ours?
And if so how bad is it- damaging bad or mildly bad?
What would be a normal amount of loss for a system this size?

Regardless I’ll go around and replace those air vents and take a closer look.

neilc

bad enough to put the effort into finding and fixing,

another spot to check is the sightglass,
close top and bottom valves one at a time,
if top valve is closed, and water rises, top glass seal is loose or bad,
if bottom is closed, and water drops, well, you would probably see that anyways,
but both are worth checking,

I've also found the brass fittings to the LWCO, the brass tube, cut wrong,

so many options

Jamie Hall

Yes, it is too much, and will shorten the life of the boiler. To give you an idea of use, Cedric -- the main system I care for -- uses about 3 gallons of water per year exclusive of the low water cutoff blowdows, and is a 400,000 BTUh system.

EdTheHeaterMan

I like that Jamie gives his heating equipment names. Maybe I will call my heat pump HAVoC. There is my Dyslexia kicking in again.

AdmiralYoda

I'm sure this has been asked before....but what is a good way to find leaks when you cant hear or see steam leaking? There is a million places it could get out. Even though I'm adding a couple gallons per month now rather than per week it does suggest that I have more leaks.

Jamie Hall

Short of using a tracer gas -- not particularly recommended -- I think it comes down to sheer luck and a healthy dose of suspicion, together with maintenance. System type has a lot to do with it. A system with packless valves, such as many vapour systems had, and few vents (ditto) operated at very low pressure will have much less loss than a system with conventional valves and lots of vents on radiators, for instance.

jhewings

@AdmiralYoda I have used tissue or toilet paper to check around each radiator valve while the boiler is running. A very small amount of water will show up on the tissue paper. I have read here use a mirror at the vents. I haven't tried that.

ScottSecor

With a typical sized residential steam system in good shape we would expect about a gallon per month usage in the colder months. Your system is larger, as such I would expect about two gallons per month.


With regard to chasing down steam leaks (especially in homes), I find that my eyeglasses do a pretty good job. If they fog up when I walk into a room, there's a big leak. If I take them off and wave them near the radiator vent or the radiator valve and they fog, there's a leak. I've also used a ceramic regular old coffee cup a few times with good results, the cup surface gets damp (darker color cup seems to work better).

Derheatmeister

If you cannot find a leak on your heat distribution/Rads/vents you could have a leak on your HX (Heat exchanger/Boiler).. A combustion could shed light on this..

Jamie Hall

Whatever, don't get exercised about a significant leak. You'd know about that. Yes, the water consmption is high, and it's worth the effort trying to find the culprits -- but it's not going to be anything dramatic.

bipbap

Ok thanks for all your thoughts on the matter.
I will try to check it all out!