Installing Gauges on Aircon Condensers

[scottinsydney]

Is it possible to install gauges on the aircon units to monitor gas levels? Does anyone have some photos of this? Could you point me towards suitable products on ebay or the web please.

 

[rustybucket]

It is, and I've seen it attempted a couple times. The issue they both had was reliability of the sensors. I'm not sure they ever found a sensor that would last any amount of time.

And when the sensor goes you have to evac and recharge the system to change it.

Maybe there are sensors available that are long lasting and reliable?

 

[brettportzer]

The MarinAire self-contained units have gauges built in, so it seems possible?

 

[Pascal]

I have them on my Flagship chillers. One of them popped a leak early on and had to be replaced. Not sure they re that useful and if I would do it again. The main benefit is being able to compare both chiller pressures to spot a water flow restriction before it triggers an HIPS

 

[krush]

You would want to make sure you have schrader valves on the connection to the gauge, or some type of valve to isolate the gauge to change it when it eventually fails.

 

[scottinsydney]

OK. Thank you for the replies.

In that case could I simply purchase a three hose aircon technician's gauge set and do this test myself every so often? What parts would I need to do this and what is the proceedure?

I am trying to track leaks and not be so beholden to the marine aircon guys who come out every couple of years when two or more aircons are low on gas.

There has to be a better way to monitor these things.

(Last technician did not close and test the valve properly and gas all leaked out within a month. I found this leak myself using the blue liquid leak finder. Utter waste of $2000 in service fees.)

 

[Captain Ralph]

Most remote condensing stations have the schrader valves. The big valves are not usually messed with for testing and topping off.
Self contained units just have schrader valves.

Hooking up gauges can be quick but a lil gas loss is going to happen. If you keep monkeying around with them, one schrader valve will not seat and leak all out.
Gauge hoses leak also.

Question; Do your systems have low pressure cut off switches? This would be a smarter tool IMO.
Shuts off the compressor when low on gas. Then top off when really needed.
If your hands are constantly on it, something will happen; Murphy says so.

If you have to have something for your interactive craving (looking for trouble); Have some stop leak with dye installed in them.
Auto leak sealer and with a lil black light, you can spot check for leaks and not touch anything.

 

[Briankinley2004]

you can install a site glass in the liquid line as long as they are not capillary tube systems.

the ones in this link look cheap but give you an idea of what they look like. I would want to solder them in myself

you should only have an occasional bubble

https://www.ebay.com/itm/1338080353...044&customid=2599d2e57b9319ca9c22b1b49e60933a

 

[krush]

If you just want to know if it's low on happy gas, just use your hand. Feel the return line to the compressor, it should be cool. And even slightly cool where it enters the compressor.

No cold, too low.

 

[scottinsydney]

Thanks again for the replies.

It would appear that installing gauges on all seven condersers is fraught with difficulty.

Here is a valve... similar on all seven condensers . This unit is low on gas. I guess thats why there is frost on valve.

Is this what is referred to as a schrader valve? Of the seven Cruisair condensers, some are 40 years old (going well) and some newer. Two have been upgraded to SMX11 controls and show an alarm if not happy.

Surely it cannot be difficult to service these yourself if you had the gauge set, a vacuum pump and a bottle of gas.

 

[Captain Ralph]

Is this what is referred to as a schrader valve?


View attachment 62699

A schrader valve is like a self sealing inner-tube air valve.

 

[Captain Ralph]

Here is a valve... similar on all seven condensers . This unit is low on gas. I guess thats why there is frost on valve.


View attachment 62699

There may be a more correct name, I just call this valve an assembly valve. In a closed position as delivered new, It would hold the pre-charged Freon gas and oil within the condensing station, After installation and the evaporator & lines are drawn down, These valves are opened, Releasing the gas to the evap and enabling the system to run.
Usually, never touched again,,, unless there are no service nipples available from around the compressor. Even then, the low assembly valve would be adjusted because it does not have a schrader valve in its service nipple.

This high pressure side valve has two 1/8" service nipples. The nipple under the red cap has the schrader valve in it. Here you would not need to use the assembly valve to check high pressure.

Look up around the compressor. There may be one or two more of these service nipples. Hopefully under blue & red caps.

Once that valve de-ices, there is a small gland nut at the base of the valve stem. Like an old hose bib, tighten that down to stop your gas leak.

 

[scottinsydney]

Thanks for photo of Schrader valve.....So what are the valves on our condensers called? They seem to have two parts... a shoulder that turns (and where bubble leak is) and the neck which also turns.

LOOKS LIKE CAPT RALPH HAS JUST ANSWERED THIS!

 

[Captain Ralph]

Surely it cannot be difficult to service these yourself if you had the gauge set, a vacuum pump and a bottle of gas.

I remember prepping some boats to ship to AU.
The AU Customs was very through on the paper chase and required services before the boats were allowed in.
All A/C systems had to have the freon gas removed and re-charged with nitrogen.
Any ice maker, wine cooler or fridge that had a service nipple was included.
A stack of papers for each option was required also.

I had just assumed from that exercise the Australia rules were tougher on Freon than here in the US where it gets harder every day for DIY A/C services.
Check into your DIY R-22 & nitrogen supplies and laws, before making plans to fix your self.

 

[Captain Ralph]

View attachment 62702

Was just thinking;
A frozen high side valve?
Short stem leaking?

That valve may not have been returned to it's full & open operation position.
Compare that stem height to other systems valves. I think it should be up another 1/2 inch.

Our Bert is on the hill 60 miles away so I can not cheat and peek at my A/C units.
I'll be on Wills Hatt later today, I'll peek at his and double check my thoughts on stem height.

 

[cww]

I wouldn't bother. On a/c's that have permanently mounted gauges, they're always a prime source of leaks.

 

[Captain Ralph]

Found a valve for pictures. The stem is short in operate mode. In my pictures are a good look at the gland nut. Like a hose bib gland, let it un-freeze and snug it a bit.

Soapy water test it for leaks and tighten a lil at a time till it stops leaking.
Soapy water test the caps and connect also.

Ensure you rinse all the soap away, Some soap will act as a corrosive.

 

[Captain Ralph]

Here are examples of the service nipples with schroder valve I was trying to explain. Without messing with those installation valves, attach gauge hoses here.
Remember to always test for leaks after removing the hose.

It is the blue or low side you ad gas to. The High side should have a red cap. Look for discolored tubes to help ID the high (hot) side.
Unless I'm trouble shooting an issue or not familiar with a new to me unit, I rarely connect to the red or high side.

 

[Captain Ralph]

(Last technician did not close and test the valve properly and gas all leaked out within a month. I found this leak myself using the blue liquid leak finder. Utter waste of $2000 in service fees.)

$2000 in fees??

Whole bill or just service (Labor)?

Did you call them back to fix that leak they induced?
Exiting rule; Always check for leaks on anything touched before leaving.

 

[krush]

Thanks for photo of Schrader valve.....So what are the valves on our condensers called? They seem to have two parts... a shoulder that turns (and where bubble leak is) and the neck which also turns.

LOOKS LIKE CAPT RALPH HAS JUST ANSWERED THIS!

View attachment 62702

It's usually called a "king valve" or service valve. Proper terms are backseat, front seat, mid seat for positions.

The leak is not a huge deal. There is usually packing that can be tightened down to reduce the leak, the leaking should be minimized when the valve is backseating in normal operation positions, and then the cap is supposed to do the secondary seal to keep the gas in (use nylog)

Watch this video for better explanation.

https://www.youtube.com/watch?v=J0hyVhJyyD0