Does manometer oil evaporate?

Does manometer oil evaporate?

PostBy: lsayre On: Sat Oct 26, 2013 3:55 pm

Every once in awhile I check the zero on my Dwyer 25 manometer, and occasionally I find that the zeroing dial needs to be cranked in (clockwise) a bit to bring it back to reading zero. I figure that at some juncture I'll run out of in-travel on the zeroing dial. It appears to me that the oil is evaporating over time. Can this be correct, or is something else going on here? Will it eventually get to where I need to add additional oil?
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (if I ever get it fixed)

Re: Does manometer oil evaporate?

PostBy: Freddy On: Sat Oct 26, 2013 5:15 pm

lsayre wrote:Will it eventually get to where I need to add additional oil?


I experience the same thing.... every year or two I have to add some oil....not much, but some. It's going someplace! Evaporation? Leaks through the tubing like air from tires? A neighbor takes some with a Q-tip to oil his rifle? I don't know, but it does go someplace. Now.... each time I have purchased a new Dwrey 25 it has come with a bottle of oil. After filling there is always some left over, enough at least to top it off for a few years. You can buy just the oil from Dwyer, but it's not cheap....mostly because of shipping.
Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

Re: Does manometer oil evaporate?

PostBy: lsayre On: Sat Oct 26, 2013 5:44 pm

I wonder how many people are looking at their Dwyer manometer and wondering why they have lower than normal draft for this time of year, when the real problem is that some of the oil has evaporated and they are thereby getting a false low reading, whereby they simply need to disconnect and dial in a new zero?
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (if I ever get it fixed)


Re: Does manometer oil evaporate?

PostBy: Lightning On: Sat Oct 26, 2013 5:57 pm

I calibrate mine weekly at minimum just by pulling the brake line out of the pipe and checking for zero. Over the summer I did notice the reading fell a bit and had to recalibrate it at start up this year.
Lightning
 
Hand Fed Coal Furnace: Clayton 1537G
Coal Size/Type: Nut Size / White Ash

Re: Does manometer oil evaporate?

PostBy: Wiz On: Sat Oct 26, 2013 5:58 pm

lsayre funny you mention oil evaporating. Yesterday my draft showed -.05 while stoker was on idle, I thought wtf is going on. No big deal I'll just zero it back in, that's when I realized that dial was already max clockwise. :notsure:
Wiz
 
Stoker Coal Boiler: Keystoker Ka 6
Coal Size/Type: Casey Junk Coal :(

Re: Does manometer oil evaporate?

PostBy: McGiever On: Sat Oct 26, 2013 7:19 pm

Dwyer Magnehelic use no oil, so never an oil issue with them. ;)
McGiever
 
Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hot Air Coal Stoker Stove: HARMAN MAGNUM
Hand Fed Coal Stove: RADIANT HOME AIR BLAST
Baseburners & Antiques: OUR GLENWOOD 111 BASEBURNER "1908"
Coal Size/Type: PEA / ANTHRACITE, NUT-STOVE / ANTHRACITE
Other Heating: Ground Source Heat Pump
Stove/Furnace Make: Hydro Heat /Mega Tek

Re: Does manometer oil evaporate?

PostBy: Keepaeyeonit On: Sat Oct 26, 2013 9:35 pm

:yes: McGiver you are so right,
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but when I had a #25 I found the oil seeped out the threads on the plastic knob and I would have the same problem but not no more :D .Keepaeyeonit
Keepaeyeonit
 
Hand Fed Coal Stove: Hitzer 983 insert
Coal Size/Type: Mammoth nut
Other Heating: oil furnace,and a crappy heat pump

Re: Does manometer oil evaporate?

PostBy: lsayre On: Sat Oct 26, 2013 9:38 pm

Nice! What are the other two monitors in the picture tracking?
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (if I ever get it fixed)

Re: Does manometer oil evaporate?

PostBy: Keepaeyeonit On: Sat Oct 26, 2013 9:46 pm

Middle one is the flue gas temp between the stove and baro,and the lower is the black pipe temp at the clay liners.If the lower one works good then I will replace the middle one with the same unit but with a different thermocouple.
Keepaeyeonit
 
Hand Fed Coal Stove: Hitzer 983 insert
Coal Size/Type: Mammoth nut
Other Heating: oil furnace,and a crappy heat pump

Re: Does manometer oil evaporate?

PostBy: lsayre On: Sat Oct 26, 2013 9:53 pm

Is your Magnehelic a Model 2000-00N?
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (if I ever get it fixed)

Re: Does manometer oil evaporate?

PostBy: Keepaeyeonit On: Sat Oct 26, 2013 11:02 pm

No I think it's #2000-00 not #2000-00N.
Keepaeyeonit
 
Hand Fed Coal Stove: Hitzer 983 insert
Coal Size/Type: Mammoth nut
Other Heating: oil furnace,and a crappy heat pump

Re: Does manometer oil evaporate?

PostBy: SMITTY On: Sun Oct 27, 2013 1:19 am

Just realized a couple weeks ago these damn things do indeed have evaporating oil ... so that tells me it's not really "oil" ... but anyway ....

Be carefull adding the stuff. I put less than half an oz in there .. and I went from not being able to zero it in the negative, to not being able to zero it less than .04"! Figures ... Now I have to do math every time I look at the damn thing ... :x :lol:
SMITTY
 
Stoker Coal Boiler: Patriot Coal - custom built by Jim Dorsey
Hand Fed Coal Stove: Harman Mark III (not currently in use)
Coal Size/Type: Rice / Blaschak anthracite
Other Heating: Oil fired Burnham boiler

Re: Does manometer oil evaporate?

PostBy: lsayre On: Sun Oct 27, 2013 5:32 am

Every liquid has a "vapor pressure" so indeed every liquid evaporates at some rate if left open (and the manometer is open to the air on one side and to the flue on the other). Oil evaporates extremely slower than water, but eventually it does evaporate. This being a very thin and light oil, it probably evaporates much faster than a heavy oil.
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (if I ever get it fixed)

Re: Does manometer oil evaporate?

PostBy: Dennis On: Thu Nov 07, 2013 8:03 am

after 4 years my oil had evaporated to nothing on the scale,then of course i over filled it and had to syphon some out,(boy that red oil tastes like crap) and then had a vaccum block after that.After letting it sit over night it's all back to normal.
Dennis
 
Hand Fed Coal Boiler: AHS/WOC55-multi-fuel/wood,oil,coal
Coal Size/Type: Anthracite/stove size