Be honest now - Would you....

[Rtic]

Would you "twist" the rules and regulations of refrigeration to save money for you and/or the customer? Or maybe always follow the rules and regs. I mean do you always use a gas recovery system, do you sometimes fit a part that "will do" but shouldn't be.

Be honest, you only have to vote, but comments would be interesting, and maybe a story or two.

[Rtic]

Also please note that that No one knows what you voted for - just in case you’re concerned what others may think

[monkey spanners]

I've been using a recovery machine for years. I had to buy my own on the last company i worked for as they would'nt supply one! Still, when i left i had all the tools lol and only had to find some customers.....

[paul_h]

No I wouldn't break the regulations just to save the customer money. And breaking any regulations would never save me money, my time gets billed to the customer, so there's nothing to save on my end, the risk is a fine to me, not them. Not to mention do it once, then they expect you to do it all the time, just to save them money.
I'd rather do a job right and get no call backs, than to keep a customer that uses you just because you're cheap and bend the rules for them.
So in the end, do it right, have no risk of fines, blow off the dodgey custmers, get a decent income due to no callbacks, fair prices charged out, cowboys be damned, hope the government catches the lot of them.

[taz24]

Be honest, you only have to vote, but comments would be interesting, and maybe a story or two.

I have voted but I feel that the question is not specific enough.

For example have you ever speeded in your car to get to a service call?
Have you ever worked on a site without a full risk assessment or carried out work without a work permit?
Have you ever vented gas because reclaiming it would be time consuming?
Have you ever fiddled your hours to get a little extra cash to pay for your next holiday or christmas?
I could go on but I think I have made my point. I'm not going to incriminate myself by answering my own questions but I would bet most of the above offenses have been commited by most of the posters on this forum.

taz.

[The Viking]

Taz,
Not only a good engineer but also psychic!

[US Iceman]

If you are willing to cut corners on regulations, what other compromises are you willing to make?

Do the job right the first time and avoid repeat calls to re-fix the same problem over and over.

[Rtic]

I mean on the job - Directly connected with refrigeration

[Sinke]

...Who made rules?...
...rich countries,like yours or...
...survive is only matter....

[PaulZ]

I agree with paul h there are too many shonky blokes out there and they give the good honest fridgies a bad name.
Those customers who want a cheap job can go to these guys as far as I am concerned.
Remember you always get what you pay for.

[Rtic]

I agree, many a times we have been to a job which has to be sorted due to past shoddy work by another engineer.



It’s also amazing how many customers say "If you cut corners, I don't mind", but at the end of the day if the job is done wrong it means more problems in the future Just last week my dad sacked one of our employees, we found out that he soft soldered EVERYTHING, when we supply Oxy acetylene for all our employees.

[airconadam]

no way thats shocking soft solder:eek: that takes the p#ss. I voted for once or twice but stay by the book but really when i think about it now, i dont cut any to tell you the truth, like some one has said there it doesnt make us money just makes us look bad thanks alot :D

adam

[Richard Hillsid]

I follow the rules to the book, lots of shady work around, some I wont even repair, have all the permits plus electrical, not going to fight no insurance company if something goes wrong.

[Tycho]

If you are willing to cut corners on regulations, what other compromises are you willing to make?

Do the job right the first time and avoid repeat calls to re-fix the same problem over and over.

Spend 30 minutes extra, doing it right the first time and you'll avoid getting called out three o'clock sunday morning on something you knew might fail, instead of just "Making it work"

[Dan]

I think the intent and mandate must always to be doing things right. Following the rules is often a good guideline, but I find most "Purists" are always in a position of plausible deniability where they can innocently claim they had no idea poor practice was implemented, yet they maintain the guideline on profitibility quite admirably as they look at technician's who go by the book and lose bids or have their bills negotiated because they followed the rules.

I service supermarkets. Each one of which is likely venting more refrigerant than hundreds of self-contained pieces of equipment we work on.

The larger sin or perhaps irony is that by US laws, the supermarkets are within acceptable guidelines if they lose 4 lbs of an HCFC refrigerant a day, whereas, if I have a technician who vents 15 ounces of 134a into the atmosphere on a self-contained peice of equipment, I risk a $25,000.00 fine.

There are laws and they should be followed. But there is also a view of the greater good and understanding of the spirit of the laws we put in place. I find it insane that we are still piping supermarkets with 5 miles of copper pipe and close to 1,000 solder joints, flares and valves all of which are likely sources of tiny to large leaks, when we could at least be using glycol for medium temperature, which is a proven system that posts competitive energy usage with the other systems currently in place.

[flyboy3b]

since im new to this trade, i have not had the chance to cut any corners, but i will say this...
in any business, there are the possibilities of a shortcut. after 31 yrs of being self-employed, ive learned to judge what corners can be cut without losing the quality that i would like to see. people depend on my honesty over my ability.
so,, in answer to the question, yes, there are times when i would opt for a shortcut, depending on the situation. do i look for the "EASY" way out,,, no

[Andy]

Hi Guys:)

what about BSEN378 does everyone carryout a strenght and leak test everytime they break into a system, I think not:eek:

Quick pressure to 200 psig and a vac, is the most we can hope for;)

Would that be an example of rule breaking.

What about the VRV with the leak that is found and topped up, without knowing the charge in the system.

I would rather bend the pressure test than guess a VRV charge:) both are rules that are broken everyday:)

Common sense plays a part and so does experience, not much need to strenght test when you are changing a flare drier, but accoring to BSEN378 you should.

Kind Regards Andy D:)

[rrvilla920]

I suspect that a prime example of bending the rules is another new thread I have seen entitled "can anyone commission a new system". Have a read. Although maybe not so much a case of bending the rules as, bodge it and scarper!

[Pooh]

Unfortunately in the trade today there are lots of people out there that do not break any rules if you ask them because they do not know what the rules are in the first place. The number of guys I speak to who do not know what COSHH stands for and as for EN378 they would not know it if it hit them in the back of the head. As discussed previously in so many other threads there are those of us that do the job properly and then there are the rest of the cowboys out there making a quick buck and vanishing into the wood work leaving us to sort out the c--p they leave behind.

Ian

[abdulazman]

No exception, no shortcuts whatsoever and if alls well ends well.

[andyh]

Forgive father for i have sinned!

But this week i replaced a 10w fan motor with a 7 watt!!

Think i'll get a recall anyone?

I also only have room for two recovery cylinders on my van of which are always are used. But this does mean me mixing refrigerants sometimes!

[thermokool]

So you mix how do you despose if it?
How do you know how much liquid is in the cylinders so it does not get over full

Would you realy put r22 and 410a together in the same cylinders how about r600

At the end of the day the customer has to pay for us to follow the rules and regs we dont

we would get fined (if found out)


simon


Forgive father for i have sinned!

But this week i replaced a 10w fan motor with a 7 watt!!

Think i'll get a recall anyone?

I also only have room for two recovery cylinders on my van of which are always are used. But this does mean me mixing refrigerants sometimes!

[andyh]

Hi thermocool,

On a couple of occassions i have recovered a system say on R22 which was from a burnout. Which i weigh into the recovery cylinder and label as contaminated.
If i have then gone onto another job to say change a compressor on r134a and lacking a virgin cylinder i would recover into the same bottle and place a new label on with contaminated refrigerants then record the weight.

I always use the recovery fill capacity of 80% but if i have placed contaminated mixed refrigerants then i would fill a lot less because of the varying mixes.

Under these circumstances i thought it better to mix than to vent.

I do try to reuse the same refrigerant in a system.

and

[Gary]

For the most part, rules are written by clueless idiots for purely political reasons.

I follow the rules I agree with. If a rule interferes with doing the job right, then to hell with the rules.

[Dan]

Rules. Laws? Manufacturer recommendations? What rules? We have a customer that uses Alkyl Benzene oil with HFC's. Seems to work. Why did they choose this path? Because in remodels they experienced catastrophic stoppage of refrigeration as the oil disolved all the oxides in the piping. Had I anything to do with this decision? Yep. And we also topped off the HP80's with R507, same as we topped off the R502 with the HP80, as pricing changed. It all gets cold and the customer gets the least expensive product that I can responsibly provide.

So much for rules.:)

[Gary]

The politicians, in their infinite wisdom, have mandated higher efficiency for A/C systems. Sounds good, but there is one small problem:

Higher efficiency means higher evaporator coil temperatures, which means less moisture removal, which means more mold.

Before you know it we start hearing about people getting sick and buildings being shut down because of mold problems.

The solution is to reduce the evaporator airflow to drop the coil temperature, but there goes the energy efficiency.

Pick your poison.

poli = many
tics = blood sucking creatures
politics = many blood sucking creatures

[winfred.dela]

Of course, it would be nice to always follow the rules. But, we all know that it's a jungle out there. :)

The question is not always on the MONEY savings, some are on the practicality of some regulations especially when the problem of TIME is involved.

One example is in the Marine Refrigeration. There are a lot of times when regulations are not applied due to time constraints.

If one have TIME, Gas Recovery is not hard to implement and there are economic advantage in doing so. Technicians in the third world can always find ways to use any recovered gas.
One question is: does the technician have a gas recovery machine? Because in our part of the world, most cannot afford to have one.

Another one is the implementation side of the rules. In the 3rd world, the government cannot afford to hire knowledgeable people to implement the rules.
So when the cat is away . . . . what do we do? ;)

:D Of course this is some sort of a confession. . .
and the above seems to justify some of my sins. . . .

[The MG Pony]

Of course, it would be nice to always follow the rules. But, we all know that it's a jungle out there. :)

The question is not always on the MONEY savings, some are on the practicality of some regulations especially when the problem of TIME is involved.

One example is in the Marine Refrigeration. There are a lot of times when regulations are not applied due to time constraints.

If one have TIME, Gas Recovery is not hard to implement and there are economic advantage in doing so. Technicians in the third world can always find ways to use any recovered gas.
One question is: does the technician have a gas recovery machine? Because in our part of the world, most cannot afford to have one.

Another one is the implementation side of the rules. In the 3rd world, the government cannot afford to hire knowledgeable people to implement the rules.
So when the cat is away . . . . what do we do? ;)

:D Of course this is some sort of a confession. . .
and the above seems to justify some of my sins. . . .

I made a recovery machine out of old fridge parts and a propane cylinder, worked great, now since upgraded, where there is a will there is a way, this be the only plannet we got.

[paul_h]

A recovery machine is just a few hand valves, a drier, compressor and a condenser.
When I started where I am now (4 years ago), nearly all the units were apprentice built machines of those specifications.
A bit hard to carry up a ladder onto a roof though, so I bought my own, which as a tradesman wasn't too pricey. Bearing in mind I live in australia, and most of them are made in U.S. or europe, so we get the worst prices. It was us$850 or 420pounds for a well built easily portable one. I had to buy it as it's compulsory in australia for every business to own one, and it's the final step for me to have all the gear I need to apply for a refrigerant trading licence anyway.

[taz24]

I had to buy it as it's compulsory in australia for every business to own one, and it's the final step for me to have all the gear I need to apply for a refrigerant trading licence anyway.


Are you self employed?

If you work for a company they should provided them!!

taz.

[paul_h]

Are you self employed?

If you work for a company they should provided them!!

taz.I bought one because I'm soon to be self employed ;)
Need one before I even apply for a refrigeration purchasing licence.

[kaspastarr]

isnt it ok to mix some refigirants but not others well 600a is flamable 410a is alot higher pressure than 22 and 600 but if he recovers say... 22 and 407c would be ok wouldnt it??
64

[Tony]

No!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[chris96]

I and every engineer i have ever worked with mix the refrigerants.
It's just more expensive to dispose of.
Nothing in the safe handling to say you should'nt.

Dean and Wood don't mind taking mixed cylinders, so i don't mind giving them!

Chris

[Tony]

Chris,

perhaps you should revisit your safe handling.

You should have been told about Daltons Law of Partial pressures.

If you don't know what its about - you should find out!!!!! :eek:

[taz24]

Chris,

perhaps you should revisit your safe handling.

You should have been told about Daltons Law of Partial pressures.

If you don't know what its about - you should find out!!!!! :eek:


They will only expanand as a partial pressure.
The total pressure only be able to get as high as the part of the refrigerant with the highest pressure.

So why would mixing refrigerants cause the pressure to rise to a dangerous level?

Not including 410a because we all know that is a one off high pressure refrigerant.

taz.

[Tony]

What happens to your discharge pressure if you get air in to your system?

And air at atmosperic pressure is at 1bara

[Tony]

Another thing to consider:

Now that the F-Gas Regs require engineers to record all refrigerants from purchase to disposal, how can you record which refrigerant has come from where and gone to where? :confused:

[taz24]

What happens to your discharge pressure if you get air in to your system?

And air at atmosperic pressure is at 1bara


A cylinder is at ambient temp and volume is an issuse not the contents.
Air will increase the overall pressure but it is not like a fridge system and therfore not at discharge pressures.
the volume of any refrigerant is the govening factor of any reclaimed or recovered refrigerant.
that is why reclaim bottles are only charged to 70% of its max contents to allow for this.

The only reason why refrigerants are not mixed is because the refrigerant has to be destroyed and can't be recycled.
If you are prepared to pay the costs then any wholesaler will and does take back mixed gases with no problem at all.

taz.

[taz24]

Another thing to consider:

Now that the F-Gas Regs require engineers to record all refrigerants from purchase to disposal, how can you record which refrigerant has come from where and gone to where? :confused:


The waste transfer will show that
X kg of X refrigerant were removed from X plant on X date.
The waste transfer can show a mixture of refrigerants and weights as long as the total does not exceede the total permisable.

As far as F gas is concerned it is not bothered how the gas gets destroyed as long as the paperwork covers the quantities.

taz

[Gary]

They will only expanand as a partial pressure.
The total pressure only be able to get as high as the part of the refrigerant with the highest pressure.


Exactly so. The pressure of the mixture cannot exceed the saturation pressure (at the current temperature) of the highest pressure refrigerant unless/until the container is full of liquid.

What happens to your discharge pressure if you get air in to your system?

Air is primarily nitrogen, which has an extremely high saturation pressure.

[Tony]

"Dalton's Law states that in any mechanical mixture of gases and vapours that are not combined chemically, each gas or vapour in the mixture exerts an individual partial pressure that is equal to the pressure that the gas would exert if it occupied the space alone, and the total pressure of the gaseous mixture is equal to the sum of the partial pressures exerted by the individual gases or vapours." Quoted from http://www.humiditycontrol.co.uk/Technology/psydef.htm

"For a mixture of gases in any container, the total pressure exerted is the sum of the pressures that each gas would exert if it were alone.

This law can be expressed in equation form as:

p = p1 + p2 + p3 + ...

where p is the total or measured pressure and p1, p2, ... are the partial pressures of the individual gases. For air, an appropriate form of Dalton's law would be:

p(air) = p(N2) + p(O2) + p(CO2) + ...

At temperatures near ordinary room temperature, the partial pressures of each of the components of air is directly proportional to the number of moles of that component in any volume of air. (We shall see in a different section that this is true because under these conditions air behaves very much as an ideal gas). When the total pressure of air is 100 kPa or one bar, the partial pressures of each of its components (in kPa) are numerically equal to the mole per cent of that component (Table). Thus the partial pressures of the major components of dry air at 100 kPa are nitrogen, 78 kPa; oxygen, 21 kPa; argon, 0.9 kPa; and carbon dioxide, 0.03 kPa." Quoted from http://www.intute.ac.uk/sciences/reference/plambeck/chem2/p01044.htm

The highest pressure individual gas pressure is for Nitrogen at 78kPa therefore using your theory air pressure cannot exceed 78kPa - so why is it 100kPa

"Dalton's Law of Partial Pressures
The total pressure of a mixture of gases, which do not interact chemically, is equal to the sum of the partial pressures. The sum of the pressures that each gas would exert if it alone occupied the volume containing the mixture.

Example
Dry oxygen gas at 713 torr is saturated with water vapour at 25 torr, the pressure of the wet gas is 738 torr." Quoted from http://www.diracdelta.co.uk/science/source/d/a/daltons%20law%20of%20partial%20pressures/source.html

This example also goes against your theory!!

[Tony]

Another thought - using your theory, if you put air contained in your hoses at 1bara into a recovery cylinder containing pure refrigerant at 5bara - the pressure would not increase above 5bara.

Now we should all know that is not true.

[Gary]

Did you not understand the term "saturation pressure"?

Okay... let's change that to "condensing pressure".

[TRASH101]

Tony I quite agree in principal of what you say in relation to Dawsons law. (not really familiar with it:o)

I hope you can now clarify my muddied thoughts on this.

If by mixing say 4 different gases whithin a container the pressure increases as the fourth is being added that surpasses the satuartion point of the gas with the lowest saturation point then I assume that whilst it is a liquid and further compression is unlikely to change its volume then the next gas follows until the gas with the highest saturation point reaches that point.

In this scenario is the rate of the pressure increase governed by combination of curves based on the compression characteristics of the gases and if the gases were similar would you see significant pressure increases thereby causing a problem as to which the mixing of refrigerants might cause:confused::confused:

Thanks

[taz24]

Did you not understand the term "saturation pressure"?


I agree.

As I stated earlier.
A cylinder is at ambient temp and volume is an issuse not the contents.

The amount of air in a clylinder will have little effect on the overwhole pressure of the cylinder.
Assumeing the ambient temp of the cylinder is not too high.

Tony you are talking about partial pressures of a gas
I have been talking about a cylinder with a liquid vapour mix init.

Cheers taz.

[chris96]

Tony,

Obviously you have to use some common sense when recovering, surely if it was as dangerous as you make out in this day and age with health and safety being so hot it'd be illegal.

Chris.

[Gary]

Let's try to explain it a little differently:

Let's say you have an evacuated container. You add gas "A" to that container.

The pressure will rise until the saturation pressure of A is reached, at which point the vapor will start to condense and the pressure will no longer rise.

Then you add gas "B", which has a saturation pressure that is higher than gas A. The pressure will continue to rise until the saturation pressure of gas B is reached, at which point gas B will start to condense and the pressure will no longer rise.

In other words, the pressure in the container cannot exceed the saturation pressure of gas B (the gas with the highest saturation pressure).

[Tony]

Gary,

Thanks for that explanation - and I accept what you are saying.

But answer this one for me then. Using BOCs data,

R409a has a saturated vapour pressure of 7.3bara at 20 degrees C

R409a is made up from R22, R124 and R142b.

R22 has a saturated vapour pressure of 9.1bara at 20 degrees C

R124 has a saturated vapour pressure of 3.3bara at 20 degrees C

R142b has a saturated vapour pressure of 2.9bara at 20 degrees C

So why is the satuated vapour pressure of the mixture less than the highest pressure of any of the individual gases?

[Gary]

Gary,

Thanks for that explanation - and I accept what you are saying.

But answer this one for me then. Using BOCs data,

R409a has a saturated vapour pressure of 7.3bara at 20 degrees C

R409a is made up from R22, R124 and R142b.

R22 has a saturated vapour pressure of 9.1bara at 20 degrees C

R124 has a saturated vapour pressure of 3.3bara at 20 degrees C

R142b has a saturated vapour pressure of 2.9bara at 20 degrees C

So why is the satuated vapour pressure of the mixture less than the highest pressure of any of the individual gases?

Because there isn't enough R22 to reach its saturation pressure.

Which brings up another interesting question: Why isn't it fractionated? Or if it is fractionated, why doesn't liquid charging leave the R22 vapor behind?

[Pooh]

Tony
are you not aware that it is the fact that at the pressures we work at in a refrigeration system we can not condense the air and that is the reason the discharge pressure rises due to the air taking up space in the condenser. In effect the air reduces the physical size of the condenser reducing its ability to transfer heat from the refrigerant.
Absolutely nothing to do with Daltons Law.

Ian

[coolkid]

Pooh,

yes I am aware of that.

[DEVIL]

with all do to respects, here in RO , i don't know of a recoveri depo that whould take the refrigerent for u , unfunrtanatly whe have to gass it all out, have no choice, i have a recoveri sistem, do to, i made myself one or 2, not hard to do u should know, bad what do u do with the output, where to go , there is no choice to say so