URGENT: Evacuation setup :(

[swampthing]

Hi Guys,

Well this is my first ever post. I am a complete newbie and have been tasked with install heatpumps. I sat a course which goes over the basics, but this was months ago and I have forgotten most of it being a goldfish brain :)

Been to HRP and bought a vac pump, torr gauge, charging hoses and a CPS two valve manifold. What my problems are is how I put this all together to vac new units and what is the procedure to vac? My training manual from the course is rubbish :(

My vac pump doesn't seem to have isolation valve at all, just connection points for hoses. I have been told by the merchants that I should connect the torr gauge to the vac pump.

I am a very visual person and a complete newbie so please keep things simple :)

Appreciate your time ;)

Take care,

J

[swampthing]

Just to add all my setup is for R410A and I have done a quick search, but just see how to connect it altogether :(

[The Viking]

If one assumes that "Anglia" as in your location, refers to Anglia in UK...

Are you aware that under current legislation you are required to, as an absolute minimum, hold a safe handling certificate?

The questions you asked opens up a whole can of worms...

[swampthing]

Yep I am certificated up for that, just haven't installed a unit since my course and the course manual sucks :(


If one assumes that "Anglia" as in your location, refers to Anglia in UK...

Are you aware that under current legislation you are required to, as an absolute minimum, hold a safe handling certificate?

The questions you asked opens up a whole can of worms...

[The Viking]

OK,
To give you a better answer, what type of heatpumps are we talking about?
Splits?

[dunny123]

Have you assisted an engineer on many installs before?Im just very surprissed at some of the questions you are asking,as some of them are the basics. If you have done a minimum of 2years assisting an engineer,you should have the knolege,and be ok in your install.

[swampthing]

Mitsubishi Heatpumps, hope that helps. But all I need to know is where the torr gauge goes, on the pump or elsewhere and just a recap on the procedure to refresh :)

Appreciate your time ;)


OK,
To give you a better answer, what type of heatpumps are we talking about?
Splits?

[swampthing]

Nope never installed before apart from on the course. I believe all you need is safe handling for split systems with less than 3 kg of refrigerant?


Have you assisted an engineer on many installs before?Im just very surprissed at some of the questions you are asking,as some of them are the basics. If you have done a minimum of 2years assisting an engineer,you should have the knolege,and be ok in your install.

[dunny123]

I would say it is very brave of you to go ahead and install it on your own,if im honest,there not simple.As for the torr gauge,you run a line into it{coected to your gauges)then a line out of it,into your vac pump.So it is inbetween the gauge,and vac pump.Hope this helps.

[swampthing]

Cheers, I do understand the basic workings of a split heat pump system, but just need refreshing on the procedures :(

I thought thats where the torr gauge goes, but looks like I am going to have to install it on the vac pump, due to the one I bought and fittings available from HRP :( Just making sure thats OK I spose.

Fingers crossed.

Take care


I would say it is very brave of you to go ahead and install it on your own,if im honest,there not simple.As for the torr gauge,you run a line into it{coected to your gauges)then a line out of it,into your vac pump.So it is inbetween the gauge,and vac pump.Hope this helps.

[The Viking]

So, It's a mitsubishi single split with one (aircooled) outdoor unit serving one (air cooled) indoor unit?

If so, assuming that the pipe run is within the pre-charged envelope...

Blue hose to system, yellow hose (from central connection on manifold) to vacuum gauge, red hose to vacuum pump.
After your vacuum gauge reached the desired reading, shut the red hose's valve (on the manifold), leave for 45 minutes and check that the pressure haven't gone up.


BUT.

If this system fails to start or breaks down, who will fix it?

Should something go wrong, no court will see you as being "suitable experienced" and you would be on your own.

Unless you are an experienced engineer "having us on" I strongly recommend that you don't do it until after you served time with an experienced engineer

(Time served can either be with an experienced engineer before you start or with Big Bubba in a 15"x10" afterwards... Your choice)
:rolleyes:

[mfakazi]

I hope im not being rude to you but wouldnt be better if you get an expirienced engineer then you can watch him doing everything then after you you can attept to install on your own which will still be very challenging...Im just saying this cos it sounds bit dangerous to me for some1 to have a go if you not sure what you doing.I mean you talking about connecting torr gauge,how about connecting ofn to the system? that could be fatal if carried out properly...

I dont mean to sound ****y but your question made us suspecious...

thank You

[Brian_UK]

STOP

Before you go any further...

You have a vacuum pump, gauges etc.

Have you got any equipment for performing a strength test and pressure test?

If not you are going to invalidate any warranty from the manufacturers/suppliers of the heat pump.

The Torr guage should be fitted to the system as far from the vacuum pump as possible.

[swampthing]

Yes, sorry I should have been more clear.

I like that setup and will sort tomorrow. I do understand your concerns and experience does count for everthing, but legally I have passed all that is required, to my knowledge, to install split systems. But I do agree with you. If you can recommend any training, books etc that would further my knowledge that would be great.

Take care


So, It's a mitsubishi single split with one (aircooled) outdoor unit serving one (air cooled) indoor unit?

If so, assuming that the pipe run is within the pre-charged envelope...

Blue hose to system, yellow hose (from central connection on manifold) to vacuum gauge, red hose to vacuum pump.
After your vacuum gauge reached the desired reading, shut the red hose's valve (on the manifold), leave for 45 minutes and check that the pressure haven't gone up.


BUT.

If this system fails to start or breaks down, who will fix it?

Should something go wrong, no court will see you as being "suitable experienced" and you would be on your own.

Unless you are an experienced engineer "having us on" I strongly recommend that you don't do it until after you served time with an experienced engineer

(Time served can either be with an experienced engineer before you start or with Big Bubba in a 15"x10" afterwards... Your choice)
:rolleyes:

[The Viking]

Legally you have passed the test to allow you to handle refrigerant. (see the picture of my daughter at: www.the-viking.eu for my views on the subject)

When it comes to things gone wrong and going to court, they are talking a different language.

"fit for purpose"
"suitably experienced"
and the likes is what the courts are talking about...

BTW, are you doing this for yourself, as self employed or as an employee?

[swampthing]

fair point my friend, it was just the vac procedure really I was unsure on, memory lapse :(




I hope im not being rude to you but wouldnt be better if you get an expirienced engineer then you can watch him doing everything then after you you can attept to install on your own which will still be very challenging...Im just saying this cos it sounds bit dangerous to me for some1 to have a go if you not sure what you doing.I mean you talking about connecting torr gauge,how about connecting ofn to the system? that could be fatal if carried out properly...

I dont mean to sound ****y but your question made us suspecious...

thank You

[swampthing]

ahhh I see what you mean, true. I am an employee.


Legally you have passed the test to allow you to handle refrigerant.

When it comes to things going wrong and things goes to court, they are talking a different language.

"fit for purpose"
"suitably experienced"
and the likes is what the courts are talking about...

BTW, are you doing this for yourself, as self employed or as an employee?

[swampthing]

Indeed I have my friend ;)


STOP

Before you go any further...

You have a vacuum pump, gauges etc.

Have you got any equipment for performing a strength test and pressure test?

If not you are going to invalidate any warranty from the manufacturers/suppliers of the heat pump.

The Torr guage should be fitted to the system as far from the vacuum pump as possible.

[swampthing]

By the way why does the gauge have to furthest away from pump?


Indeed I have my friend ;)

[The Viking]

It should be, it gives better accuracy if it is (after it reach the desired reading, it's less likely to rise if it's far away from the pump) but on small splits this might be difficult to achieve...

If you are employed, why won't your employer get a more experienced guy to show you the ropes?

[superswill]

my advise,look for a new company!

i spent two years cutting rod,uni strut,lagging pipe and watching before i got my hands on the cool tools

[eggs]

my advise,look for a new company!

i spent two years cutting rod,uni strut,lagging pipe and watching before i got my hands on the cool tools

I'm not much older than you and i remember threading 10mm bar and drilling 40x40 angle iron.
How easy do they have it now? Hilti rod cutters & chopsaws. Pah! Genie lifters ??? what happened balancing on the top of a set of nine treads with the engineer screaming at you to get a nut on the cross threaded bar??

Ahhhhh, them wert'days

eggs

[superswill]

I'm not much older than you and i remember threading 10mm bar and drilling 40x40 angle iron.
How easy do they have it now? Hilti rod cutters & chopsaws. Pah! Genie lifters ??? what happened balancing on the top of a set of nine treads with the engineer screaming at you to get a nut on the cross threaded bar??

Ahhhhh, them wert'days

eggs

ive lost track of how many 300mm rods ive cut at 290mm and how i could only ever get 2 two meter lenghts of uni strut out of a three meter lenght!! and i still cant cut straight!!!!!!!!!!!!!!!!!!!! yep they have it easy now,kids hey :D

[Larry2]

J,

I concur with earlier advice that you should be assisting on comissioning a few units before you "feel your way through" a customer's job on your own. I'm not a refrigeration tech or eng, so I have no axe to grind about newcommers to the trade. Text books will take you only so far. You will learn so much more on this site reading every evening in the archives.

It is very much unimportant where you fasten this torr gauge, compared with safe use. A bad location for the gauge will cost you time and money. A wrong procedure can harm you or the gear.

Mistakes you make could shorten the equipment life your customer paid for, even though you leave the job with the gear functioning well. Mistakes set you up for latent failures that can take time to manifest.

You need a clear image in your head of gas flow and working pressures. You need a clear vision of where atmosphere with non-condensibles and moisture and high pressures might flow, as you don't operate your manifold gauge, charging tank, valves etc in a suitable sequence.

You need to be especially mindful of test equipment limitations. Some torr gauges won't take the pressure of an R410A canister, much less the compressor head pressure without damage or worse yet catastrophic failure. You wouldn't want an unplanned rupture of your torr gauge because you forgot to valve it off and let the high side of an R410 system run. People have been hurt when high pressure blew a sight glass out and a sight glass is designed to contain high pressures.

You've been tasked with installing heat pumps. By design, their metering device operates below freezing temperatures often. A tiny bit of moisture left in the system will collect in the metering device and cause a restriction or failure. The safety device might shut the unit down when ice collects in the metering device. Or it might not. Many of these devices are self resetting and keep trying until bad things happen. These switches are really inexpensive. A welded contactor can keep a compressor running despite signals that say "stop". Contactors tend to weld "closed" when the compressor is overloaded into a restriction.

A local company experienced a hermetic compressor explosion from a restriction before the safety devices could shut it down. He had gauges hooked up and got out of the way before it blew apart. Think about a compressor casing rupturing while it's full of liquid refrigerant. Talk about legal implications that some hint at..., fortunately the homeowner was not home to watch. He got new gear on the company's dime. It's amazing how small mistakes move to the spot in the system where they cause the most damage. Such is life.

You can get a callback when winter season starts if you don't have your procedures down correctly to keep moisture out/remove moisture or non-condensables. You need a clear image of procedures to purge your hoses and even how to disconnect hoses without getting frostbite.

You need to know and respect the use of safety goggles. A fusite can blow out of the compressor. Worse, if you are not the first guy on the job, you have no clue what danger lurks inside. Is it filled with air and oil at high pressure? If you removed the cover for convenience to take a reading, the refrigerant and oil can blow out into your face. And it can be on fire. One local fellow tells me a tech leaped off a five story building jumping from the flames. No one told me that forty years ago when I worked on this stuff. God protects fools and drunks much of the time.

Yesterday I watched a "pro" solder in a new hot water tank without wearing any eye protection. There is not much more valuable in life than your eyes. Without both eyes in good shape, he would be done for life as a self employeed man. A bubble of flux could have splashed his eyes with molten metal. I've seen it happen on tiny electronic soldering.

[nubbin]

Larry2, When ever a safety officer/instructor as for one good reason why safety is important, I hold up what is left of my index finger.
Hence the nick-name Nubbin.

[The MG Pony]

Larry2, When ever a safety officer/instructor as for one good reason why safety is important, I hold up what is left of my index finger.
Hence the nick-name Nubbin.

An often neglected safety thing is all ways ensure your tools are sharp and in good order! A dull tool can bite into the work piece and kick back!

A chipped drill bit took the tip of my middle finger off, I still have magnesium fragments in there!

So be safe, use the gear and make sure the tools and gear its self is in top condition!

[Larry2]

One of the most difficult things for me to remember is that a ladder is not a tool rest. Never set anything down on your ladder unless is is secured, such as a can of paint on a platform.

I was working my house with a stepladder many years ago. I set the utility knife on the top platform. I went to move the ladder. The utlity knife came crashing down. Blocked by my glasses, the knife took a nick out of my eyebrow. I still have the scar as a reminder for what could have happened. That is why I say God protects fools and drunks.

Many things came crashing down from ladders before with my bad practice, such as hammers, etc.

That episode taught the lesson. Never set a tool down on your ladder. It will fall on you later or on your helper down below.

I guess I did hijack the gent's question, for which I appologise. I wonder how this all turned out.

Best place for a torr gauge, my guess, is the lowest part of the system, since everything else is heavier than a vacuum. I guess they are commonly fixed to the vacuum pump for convenience and if the reading holds stady with the pump off, many consider it done.

[swampthing]

Just been messing around testing at home with my vac pump, manifold and torr gauge. If I connect my Torr gauge and vac pump to the manifold, vac down to 1 torr then close the valve on the manifold to the vac pump the torr gauge goes down and thats with no system in the loop. And yes the other valve is closed as well, just testing it. Just find it strange that the torr gauge goes down???




Blue hose to system, yellow hose (from central connection on manifold) to vacuum gauge, red hose to vacuum pump.
After your vacuum gauge reached the desired reading, shut the red hose's valve (on the manifold), leave for 45 minutes and check that the pressure haven't gone up.

[Brian_UK]

How do you mean "goes down" ?

Is the reading getting less with the pump isolated ?

[The Viking]

Are your gauge electronic or mechanical?

[swampthing]

sorry I was unclear, it was late :)

The torr gauge is a very expensive mechanical one from HRP and goes down when the vac pump is isolated!

Very odd.

Take care

[Hopper118]

I'm not a fridge engineer but I am involved within the business, and I'm sorry, but after reading all of this thread it leads me to one conclusion. YOU Sir, are an accident waiting to happen! The HSE will crucifiy you and the company that employs you.
Hey Bubba! fresh meat comin!!:p

[Radiohead]

Thankfully somebody told him, a danger to himself and worse if you happened to land on site after him!!!
Don`t worry about the torr gauge, worry about the employer that would send you on a install!?!????

[nike123]

:off topic:
90% installers of single split systems in my country started like this young gentleman? And most of them even don't have any prior course. They just buy tools and follow installing instruction in instalation manual.
Equipment of Chinese origin (here, that is now more than 80% of new installs) instalation manuals instruct that you blow non-condensables and moisture from piping with pre-charged excess amount of refrigerant. There is no vacuum pumps, pressure testing and etc...

Install finished in two hours, cheap like cheap air-con. (sometimes A/C is cheaper then his instalation)

That is where we where heading before we need to match our legislative with EU. And that practice is still widely present.

[casstrig]

It seems the trade standards in your country are not what they should be, in Australia where I trained and worked for many years to gain a journymans certificate you had to work with somone for two years first which seems quite sensible,as experience from an expert saves a lot of problems later.

[Peter_1]

Best place for a torr gauge, my guess, is the lowest part of the system, since everything else is heavier than a vacuum.
Best place is as far as possible form the vacuumpump

[nike123]

It seems the trade standards in your country are not what they should be, in Australia where I trained and worked for many years to gain a journymans certificate you had to work with somone for two years first which seems quite sensible,as experience from an expert saves a lot of problems later.

Standards are improving on papers, but it is still Wild West in practice, and customers who wants cheap service and goods are those who keep things like they are now!

[bobby]

scary times lie ahead if this is the way we now train engineers.:eek:

[Larry2]

Best place is as far as possible form the vacuumpump

The pump is turned off for the final determination that an adequate vacuum and cleanliness has been achieved. With that consideration, does it make any difference where you place the torr gauge? I'm thinking in that instance, the lowest spot would be more accurate.

I think it is common practice (not best practice) to mount the gauge on a valve tree at the vacuum pump. With the pump on, that measured how large the pump is at removing leaking stuff or remaining water. With it off, does it make any difference where the gauge is connected?

Around here, I think common residential practice is to pump it down until the pump sounds more quiet and start packing the truck / call it done. :(