1/4" sight glass on 1 1/8" L Line

[SkyWalker]

hi guys, we are currently installing some systems on a site where we had no input into the kit/components selection.

basically this company has sent us 1/4" soldered type moisture indicator/sight glass. being installed are 1 1/8" Liquid lines, now they say use reducing "T" pieces (1 1/8" x 1 1/8" x 1/2" with 1/2" to 1/4" reducer) to install the sight glass "parallel" to the liquid line. they say ensure the sight glass is installed at "highest" gravitational point to ensure anye bubbles in LL will flow into the sight glass and wont bypass it to give false indication,

i can understand the theory behind it because if you had say 2 1/8" liquid line or 3 1/8" i don't even think a sight glass that big exists, at least the biggest danfoss do is 1 1/8" from what i can see.

is this common practice?

i know the easiest thing to do is just buy 1 1/8" sight glass but they refuse! lol, i also know i should just get on with it because thats how they want it but i cant help but get some other opinions.

--0-- Sight Glass 1/4"
| ... |
--------------- Liquid Line 1 1/8"

( sorry, ignore the ... i had to put them in to make it line up correctly,hope you all understand :-/ )

thanks for any input, btw its a bit late to change anything as this starts monday!

[nike123]

Check last page at bottom here (http://www.castel.it/pdf/catalogo_en/06_Liquid_indicators.pdf)! Model 3780.

[SkyWalker]

o.k lol, so they do exist bigger than 1 1/8" (28mm). what about the install i have been asked to do, any opinions?, essentially the sight glass will be installed horizontally above the horizontal liquid line.

[nike123]

o.k lol, so they do exist bigger than 1 1/8" (28mm). what about the install i have been asked to do, any opinions?, essentially the sight glass will be installed horizontally above the horizontal liquid line.

I don't have opinion since I did not ever done or see that.


You did not looked carefully. Model 3780 is brazed direct on pipe. Just drill hole in pipe and braze sight glass.

[al]

skywalker

i've seen this and done it myself plenty of times, usually the 1/4 lines are drilled and brazed directly to the pipe so the way they suggest is better!

it's also cheaper to buy a 1/4 sightglass and there in lies your price; to install;)

al

[SkyWalker]

thanks for the reply al, im pleased this is done by other people. will install in confidence now, cheers mate

[al]

no bother mate.

al

[desA]

Perhaps a silly question.

With the sight-glasses being installed at the highest point, after teeing off the large line before & after - would these not perhaps develop a gas pocket eventually? In other words - a gas lock.

The sight-glass socket sets which sit directly on the main line, would be a better idea, in my view.

[SkyWalker]

and myn but the company we working for wont budge, they say this is common practice and it saves £

[chemi-cool]

Using 1\4 sight glasses brazed on top of any size liquid line is the quickest and cheapest way.

[R1976]

Have seen these in chillers but they are not at the highest gravitational point. In fact they are probably at the lowest point.