Manometer Building

[ZachO]

For those who have actually used one of these on the fridge. What's the correct size threaded pipe I'm looking for to connect to the fridge test port?

I see a lot online about how to build one and connect it to the stove burner with the "right" sized tubing, and a lot from people who connected it to their fridge test port, but only one site actually describing the correct size pipe to fit that port, and the way they word it leaves me a little unsure of the correct size.

Anybody built one and tested their fridge? When I go to the hardware store, what actual size connection am I looking for? This will obviously determine the tubing size, too, since it needs to fit snugly over the connector.

Thanks!

[Jim Bennett]

A manometer measures the gas pressure, and can be connected anywhere in the system after the regulator for testing. Whatever connection you open to test that, to use the fitting that is used there. In most trailers I have seen it is a flare connection, usually 3/8" but sometimes 1/4".

[ZachO]

Thanks Jim.

Was there some auto-correct going on there or am I really looking for smartened futons?

One of the online instructions says 1/8" for the fridge connection, but looking at the photos it looks a lot bigger than that. Hard to tell scale, though...

I mean I guess I could buy a 1/8" threaded pipe and if it doesn't fit I'm only out a few dollars. Keep trying till I get it right, then buy the rest of the supplies.

To be clear, the fridge has its own test port in the back. There's a cap threaded into the port. You remove that cap and thread the manometer in. This site shows what this person did but I'm not confident...

[Borrego Dave]

Zach, pull the plug and take it with you. Most places have a display board set up with all the different sizes to find what your looking for.

[mary and bob]

I would guess that the fridge, stove, and water heater would all be on one line from the tanks so you are testing the whole system no matter where you connect. When I did propane installation we usually just slipped the hose on one of the stove burner valves and tested the system from there

[ZachO]

Thanks everyone. All great suggestions. My purpose for testing the port at the fridge is that it specifically isolates the fridge. So while I may not have a propane leak (something I’ll find out soon), there may be something faulty on the lp side of the fridge. I really do want to test pressure at the fridge itself.

I wanted to avoid having the fridge down for any longer than necessary, but bringing the plug to the store with me is probably the best way to go.

Thanks!

[Jim Bennett]

Originally Posted by ZachO

Thanks Jim.

Was there some auto-correct going on there or am I really looking for smartened futons?

One of the online instructions says 1/8" for the fridge connection, but looking at the photos it looks a lot bigger than that. Hard to tell scale, though...

I mean I guess I could buy a 1/8" threaded pipe and if it doesn't fit I'm only out a few dollars. Keep trying till I get it right, then buy the rest of the supplies.

To be clear, the fridge has its own test port in the back. There's a cap threaded into the port. You remove that cap and thread the manometer in. This site shows what this person did but I'm not confident...

Yeah, stupid swype typing and me not editing.

I had not realized the fridge had a test port. You had mentioned testing the fridge, and that is what through me off, as you are testing the system pressure and not the fridge.

All this said, I just ordered a manometer off of Amazon a couple days ago and it should be here tomorrow.

[ZachO]

Well I guess both. The point of testing at the port is that it's inline between the gas connection to the fridge and the burner. So there is a chance that if the gas pressure is wrong, it's actually a problem with the fridge, not the regulator and entire system pressure.

To just test system pressure I could skip the whole test port and correct-sized connection and just test anywhere with the plastic tubing. Which I also plan to do.

Thanks again.

The only one I could really afford on Amazon had, as I guess all things do, mixed reviews. Sounded like it was really easy to break the diaphragm (as in many break during shipping), and still $50. Thought about it, but decided building one which wasn't so fragile is the better bet in my situation.

[gordon2]

Zach, I bouight this one and it came with the right size fitting for the fridge test port.
https://www.amazon.com/gp/product/B0038QHTK2

I also built one to double check the readings but the one from Amazon stays in the camper. The only downside I see is that it is easy to blow out the water when the gas is turned on. One needs to turn the valves very slowly.
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Disclaimer: In no way do I endorse or suggest that anyone do repairs or testing on a propane system unless they have the proper training and equipment. You have been warned.

[Jim Bennett]

Originally Posted by gordon2

Zach, I bouight this one and it came with the right size fitting for the fridge test port.
https://www.amazon.com/gp/product/B0038QHTK2

I also built one to double check the readings but the one from Amazon stays in the camper. The only downside I see is that it is easy to blow out the water when the gas is turned on. One needs to turn the valves very slowly.
-----------

Disclaimer: In no way do I endorse or suggest that anyone do repairs or testing on a propane system unless they have the proper training and equipment. You have been warned.

Gordon, what prompted you to buy that one instead of a digital one? I do realize that they their simple design is very accurate. I opted for this one which gets great reviews. Given this price is in CAD, it is not any more expensive.

https://www.amazon.ca/gp/product/B07...?ie=UTF8&psc=1

[gordon2]

Originally Posted by Jim Bennett

Gordon, what prompted you to buy that one instead of a digital one? I do realize that they their simple design is very accurate. I opted for this one which gets great reviews. Given this price is in CAD, it is not any more expensive.

https://www.amazon.ca/gp/product/B07...?ie=UTF8&psc=1

Price, accuracy, simplicity, positive reviews, and the included test port fitting.

The page you linked to actually shows no reviews.. maybe they are under a different listing for the same product. Looks like its made in Hong Kong. Who knows how accurate it would be. My understanding is that digital manometers are calibrated using a water manometer. Assuming that is correct, why not start with the standard? The digital one is nice for someone who is doing a lot of testing.. easier and quicker to use but more subject to failure and I assume needs to have its calibration rechecked on occasion. A water manometer is more trouble to set up but I only use it on rare occasions and there is nothing to go wrong with it .

(Same disclaimer as above applies.)

[Jim Bennett]

Gordon, I would not doubt it is made in China, as the one you bought likely is. The make some great stuff over there, though do make some crappy stuff to suit many in North America looking for bargains.

I know a few people with the one I listed, and they like them a lot. The accuracy is more than good enough for what I intend it for, checking for 11" W.C. for my regulated trailer propane pressure. I will likely check others for them more than my own though.

I have made and used a homemade manometer before, but the fuss of setting it up meant it never got used.

[Paul O.]

If I were inclined toward testing my regulator, I would actually try "building" one. Using quotes only because there is not much to building a water manometer. I would look up the test port size and then go buy 3 feet of clear tygon tubing to fit. Set it up, fill with water, open the valve slowly as Gordon says and measure the water level difference with a tape measure.

[gordon2]

Originally Posted by Jim Bennett

Gordon, I would not doubt it is made in China, as the one you bought likely is. The make some great stuff over there, though do make some crappy stuff to suit many in North America looking for bargains.
....

Agreed and it might or might not be fine. I do not automatically assume that stuff made in China is inferior. But how do you know? Who tests and verifies the gauge? Yes, the water manometer might be made in China also, but it is so simple there is no worry about quality control, and it is inherently accurate by its very nature.

[Jim Bennett]

Originally Posted by gordon2

Agreed and it might or might not be fine. I do not automatically assume that stuff made in China is inferior. But how do you know? Who tests and verifies the gauge? Yes, the water manometer might be made in China also, but it is so simple there is no worry about quality control, and it is inherently accurate by its very nature.

You know, for me it is just not something I want to sweat?

[ZachO]

I guess I need to improve my search skills. Neither of those came up when I was looking. Thanks. We’ll see. Might still build one. I’ll price the supplies.

[ZachO]

I went ahead and ordered the digital one. We'll see. It's just so nice and compact...and $27.00.

[Civilguy]

I'm excited that Zach's going to test the gas pressure as I'm in the school of "this fridge will work". (I hope!)

However, I am just a little bit disappointed that no one has posted a link to a smartened futon as now that I have heard of it, I simply have to have one!

: )

[Jim Bennett]

Originally Posted by Civilguy

However, I am just a little bit disappointed that no one has posted a link to a smartened futon as now that I have heard of it, I simply have to have one!

: )

The forum would only **** out what I really want to say, so just use your imagination, Mike. [emoji41]

[ZachO]

I'm sure whatever algorithm is scanning this forum is already sending specs to a factory somewhere...