ICE COLD A/C 30's F

[brads911sc]

That would be great. Maybe Griffiths could do that if there was enough of a market..?

Originally Posted by llangston1

How about developing a cheap digital temperature switch to replace that dang capillary tube we have. Then we could set a evap temp for what we want and not have to worry about freeze ups anymore.

[kuehl]

Originally Posted by brads911sc

That would be great. Maybe Griffiths could do that if there was enough of a market..?

An Electronic Thermostat.... hmmmmm.

1) The technology has been used for years in many makes and models.
For instance the 964 AWD introduced in 1989 has an electronic thermostat probe, and the I sense one of the reasons you don't hear of many evap freezing issues is because at the factory the probe was set deep inside the evap core; not moved around or played with often.

2) Ideally the perfect system would replace both fan speed switch and mechanical thermostat with pot switches: variable fan speed control and electronic thermostat and probes, and also have an LCD display showing outside, cockpit and evap core temps. For pre 86 cars this could be a package that is placed inside the fascia of the center console or for 86+ cars it would be a sectional replacement to the rubic's cube.

3) What's been done? I've played with a prototype we put together.
Estimated the market. Developed a bill of materials and costs.
Its in a folder collecting dust. The break even point (sales) for a minimum build quantity (inventory) would occur some time after my 4th child graduates college and I enter the nursing home. And frankly I would love to see either happen earlier because my preferred epitaph should read:
"He left the world as he wished, achieving a 1 handicap, lying on a sandy beach, his children grown and happy.....",
rather than,
"He left the world crouched over a work table, soldering iron in one hand, the other hand glued to a keyboard, ....."


4) Alternatively we have toyed with just an electronic thermostat which brings us back to the issue of having the current thermostat's capillary tube sensing tube properly located in the evap core and making good contact: if the present mechanical thermostat's probe is correctly placed there are no core freezing issues (core freezing occurs more often with severe humidity and high ambient temps; and the long rides). An electronic thermostat will cost retail 2 or more times more than present mechanical design simply because of demand vs. costs.
We could build the unit here in the States, which would help job growth more positively than the present administrative plans, and offer technical support and warranty, or we could build it off shore and sell it through WalMart so everyone could buy by 'price only', and outsource the tech support "press 1 for English, 2 for Spanish, 3 for German, 4 for Russian, please enjoy the music, you are 12th in que...."

5) So the trade off (costs vs. labor) might be viewed this way:
A) Costs: pay a lot for an electronic unit which you will still need to adjust something (turn a knob in the cockpit or elsewhere because its probe is not make good contact with the evap core), or
B) Labor: pay the fair market value for a technology that has been proven to work when you do the job right (get capillary tube sensing tube properly located in the evap core and making good contact)

6) What should be the value or cost of a reliable good AC system?:
This is always a debate in the forums. The opinions range from "go for it" to "remove it and drive fast". So to be politically correct its obviously a personal choice; a preference in your life. Having good AC can be accomplished by either:
choosing a brand or technology and having an experienced shop install, or DIY as you go. In terms of which design or technology is the best I feel that each technology has its merits; you can state pro's and con's for any, much alike
which is the best tire; it all depends upon your driving needs.

So, to answer the question "how much is enough for good AC" I can only think of the answer in these terms:

(the values can be debated, however food for thought)
Decent entry cost for used 911: $15,000
Cost to rebuild and engine: $10,000 +
Cost to rebuild a tranny: $3,000 +
Cost to paint a body: $5,000 +
Cost to rebuild suspension: $1,000+
Cost to upgrade stereo: $500 +
Cost for misc 'stuff': $500 +
----------------------------------------------------
Your total investment so far $35,000

I bought my Porsche to "drive it", not to have it parked in a garage collecting dust. I want the car to die before I do. And, not having AC to drive it when the weather is 'nice' (hot usually): ............ priceless!

[wwest]

Sorry...

Modulating or moderating the level of cooling coming from a compressor type A/C is NOT an easy task. As the refrigerant evaporates you will ALWAYS get sub-freezing temperatures at the point of evaporation.

In order to get control of the system airflow temperature wise with the resolution required you would need to convert to the new "blend door" temperature moderation design technique.

That's why the current system works in the recirculate mode, controlling, responding too, the temperature of the return, system incoming, airflow rather than that of the outflow.

[kuehl]

Originally Posted by wwest

Sorry...

Modulating or moderating the level of cooling coming from a compressor type A/C is NOT an easy task. As the refrigerant evaporates you will ALWAYS get sub-freezing temperatures at the point of evaporation.

In order to get control of the system airflow temperature wise with the resolution required you would need to convert to the new "blend door" temperature moderation design technique.

That's why the current system works in the recirculate mode, controlling, responding too, the temperature of the return, system incoming, airflow rather than that of the outflow.

Good points, and:

My assumptions of the 911/912/914/930 system prior to the 964 are it was a simple 'add-on' using designs that were available at the time and there were space and location limitations.

And, controlling the temperature you desire in the cockpit with the stock thermostat really is not that difficult if you know how to do it, and if you add variations of air flow (vents and fan speed) you can tweak it to your heart's desire.

And, the reason why Porsche, in my assumption, did not try to innovate or introduce designs or technology that was available, such as was found in the 928 back during its design in the mid 70's, was either lack of capital to invest or simply politics between engineering and sales; and the 924s, 944/951 and 928 which had more complex HVAC controls, were directed at a different driver. And, if you follow the list of problems with a 928 or 964/993 with regard to HVAC controls and component issues you'll find the 911's are so much easier to address.

And, although the pre 964 system evaporator core temperature is a affected by air inlet temperature, it is the thermostat's probe and the setting at the thermostat knob that actually controls the air outlet temperature.

So, whether you ad a blend of outside air or heater air afterwards or before, to affect the air outlet temperature, in the end the reality is you still need a probe in the evaporator as a safety to reduce icing of the core... and that the present thermostat design, that does not require a "computer" or additional components that can fail, is the simplest least complex system to work with.

[KelogGes]

Originally Posted by tirwin

It didn't. This issue has been (please pardon the pun) hotly debated in at least one other on-going thread.

I'm beginning to think peace in the Middle East is an easier problem to solve than The Great Condensor Debate.

It is very simple. Cost of Condenser A and it's efficiency compared to the Cost of Condenser B and it's efficiency. It is a cost/benefit analysis.

If your condensor is working well enough, would you replace it for a 1% improvement? How about 10%? Or 50%? At what point is it economically justified for a perceptible benefit.

Now, if you need a new condensor, and you have a choice between 2 products, you could compare them based on cost vs efficiency and you'd have your answer.

Just remember that it's an A/C SYSTEM so there are other factors at play that should be considered. For example, it would be interesting to see the cost/benefit of a more efficient decklid condensor versus adding a third condensor mounted in a wheel well.

If it were me and I were trying to convince a customer to select my product, I would have the efficiency of my product tested against competitors, along with my cost versus my competitors and I might even go so far as to estimate the labor costs of installing my solution versus my competitors.

That's how I would approach it.

Just sayin'.

Tirwin I think you have made an excellent observation with your comment in many ways, you also seem interested in pfc technology in a positive way and related to what I have posted here as opposed to several others all of a sudden with a different mindset.

Everyone has different approaches sometimes how they go about things for many different reasons, sometimes the approach is not the best.

I am only a little guy with very limited funds working all by myself with a high tech a/c idea and much thought and I have proven it works extremely well!

The potential market for my 911 PFC's is very small and I do not expect to ever get rich from it! If it sells to others ok and if it doesn’t that’s ok too; I already have the satisfaction designing and personally making my own parts with my own hands and successfully attacked a Porsche 911 design problem and overcome it more than satisfactory to say the least making it work as intended.

I think I have designed and invented and made something really neat for early model 911’s a/c systems that works more than extremely well after more than a year of testing; a matched pair of front and rear PFC’s for early model 911’s; and now that I have completed this task quite by accident and it has worked so well in my opinion, I am thinking of inventing some new technology PFC’s i.e. Ferrari, Jaguar and other interesting early model sports cars, and possibly other custom size dimension applications where state of the art PFC technology solutions does not exist.

I have spent about 3 years since 2008 researching the latest technology’s in air conditioning and refrigeration condenser heat exchangers after looking at everything I could find that is available worldwide for Porsche aftermarket condensers for 911’s. Afterwhich I spent more than another year in development, design and testing before I posted anything about it here at Pelican.

I started this tread to show 911 owners they do not have to pay a ton of money to make their 911 a/c colder without having to replace all their a/c components by changing their OEM condensers AS the KEY to making a 911 cold. Unfortunately a few others completely missed this purpose!

What is unfortunate for the average reader here, because we have gotten here all of a sudden, are all the extreme serpentine proponent old technology individuals that are consumed to justify their mindset mostly because they have invested in serpentine heat exchangers probably mostly made by Griffiths and that refuse to embrace the newer technologies that ever major automobile manufacture in the world has completely switched to parallel flow micro channel condensers over all other types of prior heat exchanger technology including serpentine. Griffiths makes GOOD PRODUCTS, they are a well-established company and their older solutions work fairly well using their older technology and if you are interested in what they have to offer buy it!!! I am only into the latest heat exchanger technologies that are rapidly changing even faster than I can keep up with it, however I plan to adapt and use for my puporsess the newest/latest state of the art heat exchanger technologies and constantly switching to them as they are invented and not relying on older technology I had been using; this is one of the things that sets me apart from others.

If your into older a/c technology solutions for 911’s go to the people that supply it to fill your needs!

It seems some readers here are confused, I did not invent Parallel Flow micro channel heat exchanger technology and have only adapted this highly acclaimed and well proven technology for a for better 911 heat exchanger condenser for early model 911 Porsches that nicely fits into the Porsche original condenser body cavities in the front lip and engine compartment.

I do not really care about these adamant proponents of older, what I consider to be obsolete serpentine technology; as far as I am concerned anyone can use or spend their hard earned money on what they want and keep their mindset in the past if this is their interest and never go forward with newer proven technologies; Even though Porsche itself has switched to PFC technology on all their newer 911s as well as all their other automobile.

THE REASON
Heat Transfer Is the Key when I talk about efficiency this is what I mean!
In automotive air-conditioning, the condenser is designed to cool the system by transferring heat from the internal refrigerant — across metal surfaces — to the outside air. For condensers, more metal surface area means better performance. Conventional condensers use multi-channel extruded tubes to provide the surface area needed for effective heat transfer.
Parallel Flow Micro Channel a/c condensers can be up to approximately 25-30 % smaller in external dimension size other prior a/c technology heat exchangers, and furthermore in this smaller foot print can still produce heat transfer yhat can be up to as high as approximately 30-40 percent heat transfer efficiently. There literally are thousands of scientific studies and research papers all over the internet anyone can read that takes the time to read them that bear this out.

Furthermore for over 20 years I have spent a lot of time discussing in-depth with a professional Porsche repair shop that has worked on all models of Porsches over the last 35 plus years which happen to be good friends of mine about how to make 911's a/c cold. The sad part was at first even getting my very knowlegable friends to even believe what I tryed to discuss with them about how much better the technology is for making a 911 cold due to their very old ingrained mindset and it was not until a year later after I had been successfulling tesing my designes that they finally SAW THE LIGHT and now believe in me and what I do. You might say I have had my share of Nay Sayers and the worst is when its your long time friends LoL but I have now been rewarded because they now promote my PFC's to their customers.

FYI If you’re interested in i.e “THE VERY LATEST STATE OF THE ART PFC” Check this puppy out, “I did not design this”, but will probably adapt its technology if it’s possible into some things I am planning if legal agreements can be worked out.

[911Texan]

+1 Subscribing. - R

[tirwin]

Reid,

I have no bias whatsoever. I'm just a DIYer who loves working on my car.

That being said, I think it's important that everyone reading this thread understand their options.

So here is my advice to you. You have talked about the superior technology you are using. You have provided links to some academic studies. Frankly, and I'm saying this as an owner with an inoperable A/C that will be in the market, you will not convince me of the superiority of your product based on ANYTHING you have said so far. I am not trying to be a jerk. Facts are facts.

If you want to prove to the naysayers on here that you are right, do the following:

- Take an older 911 with operable factory A/C (not converted to 134a).
- Document the setup.
- Document the vent temps under a variety of settings.
- Then replace with your condensors.
- Tell us exactly what was changed.
- Tell us how long it took to change.
- Even better would be a video showing the procedure.
- Then document the results.
- Then tell us what the cost is.
- Tell us what the warranty is.
- Did engine temps increase after?
- Is good documentation provided?

If you do that then a consumer who is in the market will have the FACTS they need to make an informed decision. If you cannot do that, then you need to understand why people are (and will remain skeptical).

Others have contributed the questions they want to know the answers to. So build a list and be prepared to answer those questions.

I think you are very passionate about this technology. There is nothing wrong with that. But you are making emotional and subjective statements. You can stop the debate and win people over if you simply provide hard data. What do you think you are accomplishing by saying the same thing over and over?

[ratpiper71T]

Don't know if you misspoke, but wouldn't it be more beneficial or in the interest of proving his claims if he takes someone that has already done the griffiths or rennaire conversions to r134- observe all the points you spoke of--- then switch the condensers with his? This would show their advantages if there are any. Anything else would miss the point.

Reid,



I have no bias whatsoever. I'm just a DIYer who loves working on my car.



That being said, I think it's important that everyone reading this thread understand their options.



So here is my advice to you. You have talked about the superior technology you are using. You have provided links to some academic studies. Frankly, and I'm saying this as an owner with an inoperable A/C that will be in the market, you will not convince me of the superiority of your product based on ANYTHING you have said so far. I am not trying to be a jerk. Facts are facts.



If you want to prove to the naysayers on here that you are right, do the following:



- Take an older 911 with operable factory A/C (not converted to 134a).

- Document the setup.

- Document the vent temps under a variety of settings.

- Then replace with your condensors.

- Tell us exactly what was changed.

- Tell us how long it took to change.

- Even better would be a video showing the procedure.

- Then document the results.

- Then tell us what the cost is.

- Tell us what the warranty is.

- Did engine temps increase after?

- Is good documentation provided?



If you do that then a consumer who is in the market will have the FACTS they need to make an informed decision. If you cannot do that, then you need to understand why people are (and will remain skeptical).



Others have contributed the questions they want to know the answers to. So build a list and be prepared to answer those questions.



I think you are very passionate about this technology. There is nothing wrong with that. But you are making emotional and subjective statements. You can stop the debate and win people over if you simply provide hard data. What do you think you are accomplishing by saying the same thing over and over?

[Neel]

^^^^^+1^^^^

[tirwin]

Originally Posted by ratpiper71T

Don't know if you misspoke, but wouldn't it be more beneficial or in the interest of proving his claims if he takes someone that has already done the griffiths or rennaire conversions to r134- observe all the points you spoke of--- then switch the condensers with his? This would show their advantages if there are any. Anything else would miss the point.

Well, I was trying to start with the most basic set of circumstances to get a simple apples-to-apples comparison. There are a bunch of variables you can get into that makes it a slippery slope. I don't really care as long as it's solid basis for comparison. Everything on my A/C is original so I suppose I was being selfish.

[SilberUrS6]

Originally Posted by ratpiper71T

Don't know if you misspoke, but wouldn't it be more beneficial or in the interest of proving his claims if he takes someone that has already done the griffiths or rennaire conversions to r134- observe all the points you spoke of--- then switch the condensers with his? This would show their advantages if there are any. Anything else would miss the point.

I don't think it would. The reason is that someone usually goes from inop or barely functional stock to some form of aftermarket. Whether it is one condenser, two condensers or some combination of condensers and evaporator, the move from stock usually includes some sort of heat exchanger upgrade. Almost always, there is a hose change that goes along with that. And sometimes a refrigerant change.

So, if you're going to spend money replacing some portion of the heat exchanger system in your car, one might imagine that you won't go just part-way, but instead replace the hoses and drier along with the heat exchangers.

I think comparing against the stock system is perfectly legit - since very few folks who already have the Rennaire or Griffith stuff are going to change things out if the current set-up is satisfactory.

[KelogGes]

Originally Posted by llangston1

How about developing a cheap digital temperature switch to replace that dang capillary tube we have. Then we could set a evap temp for what we want and not have to worry about freeze ups anymore.

Hello llangston1


I have decided to answer your question in detail

You have some odd questions that do not make sense related to a Porsche 911 A/C system or any automobile system, furthermore you give no info on what year 911 you’re talking about or even the problem that prompted you to ask me what you did.

Sorry I am only making PF condensers

Capillary tubes are usually used in refrigerators like you have in your home, to this best of my knowledge they are not used in automobiles.
I think instead you mean thermal expansion valve not capillary tubes? Porsche uses 2 different types of thermal expansion valves for controlling liquid refrigerants into the evaporator. Let’s call them old and new styles. As you have given no information about what year 911 your talking about I am going to guess your interest is related to 1963-1989 911’s; and not the later model water cooled 911’s that use the newer block type thermal expansion valves?

if you’re having evaporator freeze ups and you cannot control this with your dashboard temperature control thermostat switch that controls your compressor clutch and turns it on and off AND is on too long sending too much refrigerant into your evaporator maybe you need a new one because either it or the temperature sensing probe that comes off of switch and goes into the inside of your evaporator is damaged or you have some other kind of problem with something else?

Anyway What I think you are suggesting being made by me to control the thermal expansion valve superheat on a refrigeration/freezer system is already being manufactured and has been available by several companies for more than 50 years I believe, unfortunately although it’s possible to use an externally fully adjustable thermal expansion valve it’s not really practical for automotive use and the cost would be very expensive to say the least compared to a normal 1.5-3 ton thermal expansion valve.

The best and newest ones are computer controlled that have the capability you say you desire, but unless you got quite a bit of disposable cash for having this convenience feature you might want to forget it. BTW Some of the multi- stacked-compressor $250,000 plus large motor super-yacht a/c systems I work on have them when price is no object.

Now after I have spent a lot of time typing to you scratching my brain and said all the above trying to guess why you said what you did in the first place

It got me thinking about how crazy TX valves are and can drive you nuts trying figure them out because most people don’t understand them properly

Bear with me please and I will greatly expand on your odd question

The Thermal Expansion Valves that control the liquid refrigerant flow into the 911 evaporator are a bit of a mystery for the average person who has only limited knowledge what it actually does and how it works (even to many technicians) in the INEXACT way they work/function to actually meter the pressurized liquid refrigerant under variable temperature loads coupled with variable engine and a/c compressor rpm. (I think I got this right for what I am trying to say?)

I think I know exactly what your frustration is related to thermal expansion valves, THEY REALLY SUCK IN THE WAY THEY METER-CONTROL REFRIDGERENT !

After I go through this next part I will do in another post about Thermal Expansion valves I am going to suggest something probably very new to you and readers to this tread that works exceptionally well for lowing air vent temps

CALLED Variable Orifice Valve A/C Refrigerant Metering (VOV), that is far superior than ANY thermal expansion valve metering device for a 911 A/C system, and have the ability to lower air vent temps approximately 12-14 degrees colder by only switching to this type of evaporator refrigerant metering device

wait more is coming to be added to my answer in more than one part

[SilberUrS6]

Originally Posted by KelogGes

Capillary tubes are usually used in refrigerators like you have in your home, to this best of my knowledge they are not used in automobiles.

Really? You're trying to sell parts for air conditioning systems for which you have no knowledge on how the temperature is controlled?

[tazzieman]

Originally Posted by KelogGes

Capillary tubes are usually used in refrigerators like you have in your home, to this best of my knowledge they are not used in automobiles.

This Genuine Porsche air con part G92857358102 says " known as capillary tube".
Is this a misnomer?

[brads911sc]

LOL, Reid, LOL

There are two components at the Evap in our 911 AC systems. The expansion valve AND the Capillary tube. The capillary tube is connected directly to the thermostat on your dash. It has a very long (4 feet) fragile tube that is filled with a gas. The expansion valve is not. Its only a value that is preset to open and close at a predetermined setting.

Wow....

Originally Posted by KelogGes

You have some odd questions that do not make sense related to a Porsche 911 A/C system or any automobile system,

Capillary tubes are usually used in refrigerators like you have in your home, to this best of my knowledge they are not used in automobiles.
I think instead you mean thermal expansion valve not capillary tubes? Porsche uses 2 different types of thermal expansion valves for controlling liquid refrigerants into the evaporator. Let’s call them old and new styles. As you have given no information about what year 911 your talking about I am going to guess your interest is related to 1963-1989 911’s; and not the later model water cooled 911’s that use the newer block type thermal expansion valves?

[911dean]

Capillary tubes are usually used in refrigerators like you have in your home, to this best of my knowledge they are not used in automobiles.


Why would I want to buy something from you?
Dean

[kuehl]

Semantics.....

"capillary"..... a tube having a very small bore

The gas filled tube of the thermostat can be called a capillary tube, alike the
copper tubes attached to the TEV.

In many instances thermostat manufacturers providing controls
for many sectors (auto, medical, processing, home HVAC, etc. ) of the market that require controls
refer to the gas filled tube (sensor) as a capillary tube:

[KelogGes]

Originally Posted by brads911sc

LOL, Reid, LOL

There are two components at the Evap in our 911 AC systems. The expansion valve AND the Capillary tube. The capillary tube is connected directly to the thermostat on your dash. It has a very long (4 feet) fragile tube that is filled with a gas. The expansion valve is not. Its only a value that is preset to open and close at a predetermined setting.

Wow....

QUOTE=brads911sc;6782662]LOL, Reid, LOL

I stand by what I said, “Early Model 911’s DO NOT USE CAPILLARY TUBES”!!!
you unfortunately apparently don’t know much about your early model 911 a/c system, what you think is a capillary tube is actually a “thermostat temperature probe” attached in your dash that only monitors evaporator temperature and controls your compressor clutch from the dash thermostat; and is in no way connected directly to the 911 a/c refrigerant gases or their metering valves


Throttling or Expansion Devices for Refrigerator and Air-Conditioner Systems



Refrigerators and Air Conditioners: Expansion Valves: Capillary Tubes and Thermostatic Expansion Valves

Written by: Haresh Khemani • Edited by: Swagatam
Updated Dec 10, 2008

In throttling devices the pressure of the refrigerant drops down suddenly and due to this its temperature also reduces drastically. This article describes various types of throttling devices being used for refrigerator and air-conditioning systems.



Refrigerating and air-conditioning systems are comprised of four important components: the compressor, the condenser, the throttling or expansion device and the evaporator. The refrigerant keeps on flowing through these components in a continuous cycle. The high pressure and medium temperature condensed refrigerant leaves the condenser and enters the throttling or expansion valve.

In the throttling valve the pressure of the refrigerant reduces suddenly and excessively. With this the temperature of the refrigerant also reduces drastically. This low pressure and low temperature liquid refrigerant then enters the evaporator and absorbs heat from the substance or the space to be cooled.

The throttling valve is fitted between the condenser and the evaporator. The throttling or expansion device is in the form of a small orifice. When refrigerant passes through this small orifice its pressure reduces suddenly due to the friction. The rate of the flow of refrigerant through the throttling device depends on the size and opening of the orifice. It also depends on the difference in pressure on the evaporator and the condenser sides.

There are different types of throttling devices, but in refrigerating and air-conditioning systems, the two most commonly used types are: capillary tube and thermostatic expansion valve. These have been described below:

1) Capillary tube: Instead of the orifice, the capillary is small diameter tubing that offers the restricted flow of the refrigerant. Its internal diameter ranges from 0.020 to 0.090 inches depending upon the capacity of the refrigerating or air-conditioning system. The pressure drop attained through the capillary depends upon its diameter and length. Capillary tubing made of copper is most commonly used.

Capillary tubing is used for small refrigerating and air-conditioning systems like household refrigerators, water coolers, deep freezers, window air-conditioners, split air-conditioners, small packaged air-conditioners etc. For systems in which capillary tubing is fitted, technicians have to be very careful of refrigerant charging as the overcharging can lead excessive high discharge pressures from the compressor, which leads to over loading of the compressor and the chances of refrigerant leakages from the system are also increased.

2) Thermostatic expansion valves: The thermostatic expansion valve is not controlled by the temperature. It works automatically maintaining proper flow of the refrigerant depending upon the heat load in the evaporator. Apart from reducing the pressure of the refrigerant, the thermostatic expansion valve also keeps the evaporator active. These days thermostatic expansion valves used with solenoid valves are more common.

Thermostatic expansion valves are used extensively in medium and large sized refrigerating and air-conditioning systems. They can be used for large water chilling plants, brine chilling plants, large packaged air-conditioners, central air-conditioning plants etc.

[kuehl]

"Originally Posted by brads911sc View Post

There are two components at the Evap in our 911 AC systems. The expansion valve AND the Capillary tube."

I sense Brad was using short hand or the least number of words to describe something:

1) The capillary tubes that throttle the TEV's diaphragm and provide equalization,
and
2) The capillary sensing tube from the thermostat that provides make/break to the clutch and pin 86 of the ac relay.

[KelogGes]

Common Metering Devise Problems
Problems Symptoms
Stuck expansion valve Caused by dirt in the system or moisture
Oversized expansion devise Causing hunting, liquid flood back to comp
Improper sensing bulb location Cause liquid flooding at comp.
Valve superheat setting too high Cause overheating comp
Valve superheat setting to low Cause liquid flooding in comp
Wrong type of valve Flooding, evaporator starving, overheating
Plugged distributor Starving, uneven refrigerant distribution
Plugged EQ line Cause starving of Evaporator
Improperly sized distributor nozzle Uneven refrigerant distribution, flooding