R22 / R410 combo manifold

[IrishJoe]

This is my first a/c season as a solo tech. As most of you remember, the first few years are almost like working for free because of all the equipment you have to buy . I cut some corners on my manifold gauges. Yellow Jacket now makes 404/ 22 / 410 combo gauge set. I bought it hoping to keep money in pocket. QUESTION: I know you can't mix oils, so is a nitrogen flush, or pulling a vac on them to keep from contamination, or does it even matter ( i think it does from my schooling?) going from a 410 system to a 22 system back to back? hope this made sence lol. Guys at the shop are saying I should'nt contaminate with what little oil might hang in the tubes between units. but i'd like other thoughts on the subject....
Thanx!

[refrige-nate]

yea technically your not supposed to mix oils...and theres no way your going to flush those suckers every single time you put them on so i would go ahead and get yourself a nice set of both gauges, one for 22 the other for 410. its one of the most important tools you have as an A/C tech so buy good gauges

[mark beiser]

If you've got enough oil left in your manifold and hoses, after disconnecting from a system, that you need to be concerned about contaminating the next system, you seriously need to rethink your procedures...

I'm not a fan of analogue gauges at all, but combo R-22/R-410A gauges are a particularly bad idea.
The working range for an R-22 system is compressed into the least accurate part of the gauge movement, and the resolution is to low to be anything like accurate.

[weber]

Your biggest concern with those gauges shouldn't be about switching from a 22 unit to a 410 unit unless your leaving your hoses full.

The biggest problem with these gauges are the saturation scale. Because your crammin' that scale in there with the rest, it becomes very inaccurate.

This is why others and myself, recommend digital gauges.

If your using these gauges, I recommend you use a p/t chart to get your sat temps.

[IrishJoe]

[QUOTE=weber;1910727]The biggest problem with these gauges are the saturation scale. Because your crammin' that scale in there with the rest, it becomes very inaccurate.

Good point, hadn't thought of the pressure diff, abstracting the readings. Thanks.

Why do you think an industry leader like YJ decided to put out the product?

[weber]

Because its a great product, that is rated at more then one refrigerant, making it essential to our industry and to saving time.

But the fact that the scale is to small to get an accurate reading has nothing to do with the manufacture, it has to do with the accuracy of your calibrated eye. If you have a microscopic eye, then you have nothing to worry about

[JBM1000]

Glad to notice the concern was for the saturation "temperature boiling point" verses just the pressure. I run into techs that never think temps with gauges, just hoping for 40' I guess and juke joint jive'in the sub cooling & surperheat.

Don't even want to go there with the 30 other factors that matter!

[JWB]

[QUOTE=weber;1910727]Your biggest concern with those gauges shouldn't be about switching from a 22 unit to a 410 unit unless your leaving your hoses full.

The biggest problem with these gauges are the saturation scale. Because your crammin' that scale in there with the rest, it becomes very inaccurate.

This is why others and myself, recommend digital gauges.

QUOTE]

So does that mean that we shouldn't leave our hoses full with ball valves and sealtite ends if we are using digitals on 22 & 410? Can you please elaborate?

[weber]

My opinion you should never leave refrigerant on your hoses and put them on another unit.

Especially if you are going from 22 to 410a.

But even going on service calls of the same refrigerant, I dont like to spread aids from one unit to another, I perfer to strap it up.... and be sure!

[Skrammy]

Delete

[Skrammy]

My opinion you should never leave refrigerant on your hoses and put them on another unit.

Especially if you are going from 22 to 410a.

But even going on service calls of the same refrigerant, I dont like to spread aids from one unit to another, I perfer to strap it up.... and be sure!

Another way to look at it is...would you take a thermometer from someone with the flu and stick it in your mouth after they used it?
It can be like spreading a sickness if you dont empty out your hoses. You can spread acid from one contaminated system to a brand new install!! Plus if you empty out your hoses, it will keep your analog gauges a little more reliable. You dont have pressure sitting in them 24/7.

Chad
Indy

[johncavh]

yes i do usually keep pressure in 24/7

[Texas-Tech]

there is no reason to keep pressure in your hoses, what small amount of air that may get in between uses in not worth worrying about. Bleed um out when you hook up or blow nitro through before use. It is possible to take it to extremes and thats not necessary.