Digi-Cool® DRSA™ Drenching (x2)

 I hesitate to even relay this story because I’m not certain if it is a testimonial about the DC DRSA or my ignorance.  I was on a call about 35 miles from the shop, heat pump found a bad reversing valve changed it, recharged and was wrapping things up – started to drizzle a bit – first good possibility of some soaker rain we’ve had for a very long time, so I was a little preoccupied with that.

Anyway I’d carried two arm loads of stuff across about a 50 yard walk from the outdoor unit, trying to get my tool bag into the van before the tools got too wet. I hung the DRSA hook on the cross bar of the ladder rack in the back of the van – I really don’t need to illustarte my ignorance beyond that statement I wouldn’t think. Got the other things loaded in the side door – rain began to pick up so I jumped in the front to do my paperwork – got it signed jumped back in and took off, no thoughts at all to the DRSA hanging on the ladder rack. I drove probably 25 or 30 of the miles on the way back to the shop, 40 -50 mph country roads pouring rain when I caught a set of headlights in my side mirror flashing on and off high beams, low beams – I’m thinking hmmmm must be driving too slow for this idiot, screw him. So we got back to civilization again ,the country road gave way to a split 4 lane and the guy pulls up next to me blowing his horn, so I roll my window down and  he says, are you friggin’ blind, I been trying to get your attention for 20 miles…….no I didn’t even notice I lied, my windows are tinted too dark.  Well you got something with tubes on it flapping around back there behind your van thought you might like to know….and he abruptly drove away I pulled over at the next place I could and there was my baby – the hook, thankfully had slid along the cross member of the rack and wedged in to a pipe carrier or I’m sure it would have taken flight. Scuffed the paint on my van where the manifold was rubbing it – brought the set in with me this evening…..botta bing….took a lickin’ but it’s still tickin’……

Honeywell® SmartValve™ and the SupCo® SmarTester™

We are interested in talking to technicans that have experience with this instrument in a field setting. As the name of our Journal indicates, we are pro-digital, actually not even necessarily pro-digial – we like to talk about the instruments that are available to the technician to make him a better, more effective – efficient technician. Unfortunately most often the only resource for information on instruments come from their respective OEM’s. At least that has been true up until HVAC PROTech.com® introduced the Exclusive FieldTest Evaluation Boards.

We have industry recognized authorities with published documents and Articles relevant to the subject of the troubleshooting procedures and techinques that are unique and specific to the Honeywell® SmartValve™ we are currently in the process of scanning and uploading such a publication from Timmie McElwain – we will make it available exclusively to our members. The oustanding issue however, remains –  is the SmarTester™ a legitimate instrument? Will it tell you anything that the valve itself will not tell you.

We have a SmarTester™ currently in use on the boards but it has yet to achieve the status of a FieldTest. A single use proved the instrument capable of troubleshooting an ignition circuit quicker than conventional techniques – but – single use is not adequate to prove the instrument worthy of inclusion in our, “Gotta Get-It” category. So we would like additional input from the readers of the Zeus Journal. You have one – you use it – useful or useless, please let me know at digital.zeus@yahoo.com   

Enthalpy Charts: What They Can Tell the Technician

Click the Thumb for a Detailed Image.

Think the only place for an Enthalpy Chart was the classroom or on an engineer’s desk – nope,  not even close. Learn how to plot equipment operating parameters. Find out what all of those lines and curves are really telling you. Discover……or rediscover one of the most effective diagnostics tools you never knew you had.

Comprehensive Enthalpy Article Index in the HVAC PROTech.com® Technical Archives Library – and Discussion on The Technicians Forums | HVAC PROTech.com®

An Open Letter to Robinair®

Has Robinair® forgotten their roots? I know I tag the SPX company pretty hard just about every chance I get. Like many of the guys that will read this I have thrown good money after bad on Tif® and Robinair® digital manifold gauges. In reality a part of me hates to take pot shots at Robinair® – they were an institution, a tradition – an icon of this trade. Remember when Robinair® was the name in manifold gauge reliability and performance? Their 3 gauge heat pump specific manifold was the very first set I ever owned – some 25 years or so ago. It got stolen and I’ve been looking for a replacement set ever since – apparently discontinued around 10 years ago.

That was when the name was respected among the craftsmen of our trade, before the first attempt at a digital revolution. In all honesty at least a degree of respect should be due them just based on the concept and attempt alone, where they fell short was lack of field testing and product support, that was especially true of the Tif® version.

Today’s a new day though. The technology has been field proven for a number of years now – Digi-Cool® and Testo® are odds on favorites for making the analog manifold gauge obsolete much in the fashion that Fluke® made the analog multi-meter obsolete. So I wonder where is Robinair® in this equation? Have they decided to abandon the trade completely and focus on the MAC trade aside from what sales they can extract from the analogs that some techs still purchase or their recovery equipment? Sometimes quietness is an admirable quality and a valuable commodity – that isn’t the case in this instance unfortunately.

Can that quietness be translated as a submission by Robinair® – we can’t compete in this segment of the market? We’re too far behind to establish a presence in the digital market? You see that’s my point – quiet in this instance is not good, it leaves whatever the facts may be open to interpretation and unsubstantiated theory. Both of which can be killers. I don’t understand their obvious lack of a proactive position relevant to digital technology as it applies to the manifold gauge. It makes no sense – unless they are admitting defeat.

The days that were -when Robinair® could initiate sales simply by attaching their branding to it have long gone – maybe that’s the reason for the quiet. Make no mistake, the development of this technology into a field applicable instrument is no easy task – nor is it an inexpensive one – perhaps another reason that Robinair® by all outward appearances sits idly by as Digi-Cool® and by association Yellow Jacket® and Testo® continue to dominate the digital manifold gauge market, and in the interim J/B® Industries, Refco® and Mastercool® have all introduced their own respective models.

Come on Robinair® we – the technicans of this trade are as a whole a loyal group of folks. We built Robinair® into what it used to be. Why have you turned your backs on us? No screw you, no “hey we’re sorry, we just don’t know how to develop the technology.” Nothing. You just pull the products off the shelf and that’s it? Do you not owe us more than that? I’d love the opportunity to talk to the man that sits behind the steering wheel at Robinair® Just 5 minutes. Surely to God your association with SPX does not overshadow the value of your own name. It’s ok to come back to the playground and say, you know what we screwed up. We’re sorry -can I have another chance. Is that so damn hard to do? Open invitation to contact me any time you wanna play again – or to at least have the balls to say why you can’t. digital.zeus@yahoo.com

A Public Service Announcement From Your Friends at HVAC PROTech.com®

If you use the blue gunk to seal a fitting use the right amount for Christ sake. It took me a week and four visits before I moved to disassemble the system completely until I found this. This is a CPR for a small laboratory freezer.

Shot at 2008-01-13

And if you are going to install a suction line accumulator for the love of God and the refrigeration men that came before you and those to follow, dont install it backwards it says IN on one side for a reason, the oil return.

 

The Technicians Forum | HVAC PROTech.com®

HVAC Equipment Nomenclature

Ever been in the field and needed to know the significance of the nomenclature of the equipment you are diagnosing? Who hasn’t right. Some OEM’s seem to go out of their way to make the nomenclature as cryptic as possible.

That’s why we have the HVAC PROTech.com® OEM Nomenclature Thread: http://hvacprotech.forumwise.com/hvacprotech-post-16571.html#16571

Look for Articles like our Nomenclature Thread to be available for field access via Podcast, coming soon to the Technicians Forum.

The Fundamentals of Gas: An Article From the HVAC PROTech.com® Gas Technologies Board

The Fundamentals of Gas

I thought it would be a good idea to post a little bit on Fundamentals of Gas as a review for some or perhaps new to others. I will add a little on this subject as I have time.

The general composition of Natural Gas a “HYDROCARBON” that is a compound of hydrogen and carbon CH4. The major part of natural gas is composed of METHANE, about 85%, 12% ethane and other gases.

Natural gas is odorless out of the ground so an odorant (mercaptan ) is added for detection purposes. The gas is basically non-toxic but can at times displace the oxygen in a confined area.

The specific gravity of the gas is from .4 to .8 as compared to air, which is 1.0. We typically use .6 as a point of reference for charts and tables. The .6 SG means that natural gas will rise (lighter than air) when leaking as compared to LP gas, which has a SG of 1.52 and will tend to accumulate in low areas.

Specific gravity affects two things:

1. The flow of gas through orifices, also pressure upstream will affect flow.
2. The flow of gas through pipes

A gas ORIFICE is a small hole punched into a brass fitting called a SPUD.

Read the Rest of This Gas Fundamentals Article as well as Others by Timmie McElwain in our Gas Technologies Board: http://hvacprotech.forumwise.com/hvacprotech-thread2292.htmll Only at the Technicians Forum. HVAC PROTech.com®

Superheat/Subcooling:Troubleshooting Guides and FAQ's From Fieldpiece® Instruments

Troubleshooting Guide and FAQs
Superheat/Subcooling
SSX34, ASH3, ASX14, ASX24

The ‘cold beer’ test is good enough no longer. You must check superheat or subcooling to charge a modern air conditioner properly for efficient operation. Below you’ll find the most common technical questions and answers associated with superheat/subcooling measurements and the use of Fieldpiece Instruments superheat/subcooling tools. 

1. What equipment do I need?

2. How do I know if I should be measuring superheat or subcooling? 3. What is superheat and subcooling?

4. When should I take my actual and target superheat/subcooling measurements?

5. How do superheat subcooling tools work?

6. How do I use either subcooling or superheat to charge a system?

7. How do I calculate ACTUAL superheat?

8. How do I calculate ACTUAL subcooling?

9. How do I measure refrigerant temperature (the ACTUAL temperature of the refrigerant)?

10. What do I do with my ACTUAL superheat or ACTUAL subcooling measurements?

11. How do I calculate TARGET superheat?

12. How do I calculate TARGET subcooling?

13. What if my ACTUALS are far different from my TARGETS, but the system seems to be running properly?

14. Why is my meter displaying pressure when it is not hooked up to any pressure source?

15. Why does my pressure reading keep changing when I am testing superheat / subcooling?

16. Why is my PRESSURE READING displayed as “OL” (or) “-OL”?

17. Why is my TEMPERATURE reading displayed as “OL” or “-OL”?

18. Why is my SUPERHEAT / SUBCOOLING reading displayed as “OL” or “-OL”?

19. My ambient temperature reading is off. How do I calibrate temperature on my Fieldpiece tool?

Read the Rest of this Article as well as the Entire Collection of Fieldpiece® Technical Articles: http://hvacprotech.forumwise.com/hvacprotech-post-11659.html#11659 Courtesy Fieldpiece® Instruments.

Using A Two-Column Pressure-Temperature Chart

How to Use a Two-Column Pressure-Temperature Chart.

 Because the properties of the new zeotropic refrigerant blends are different than traditional refrigerants it’s useful to know how to read a two-column PT chart By Jim Lavelle The pressure-temperature (PT) chart is a valuable tool that service technicians use to check proper system operation. PT charts are most often used for three purposes: to set a coil pressure so that the refrigerant produces the desired temperature, to check the amount of superheat above the saturated vapor condition at the outlet of the evaporator and to check the amount of subcooling below the saturated liquid condition at the end of the condenser.

 

Read the Rest: http://hvacprotech.forumwise.com/hvacprotech-thread70.html

Digi-Cool® Industries: Maximizing the Digi-Cool® Analyzer

When evacuating a new system prior to start up, it is always advisable to use an accurate vacuum gauge. But if one is not available, the DRSA-1100 is extremely accurate compared to analog gauges. The analyzer reads vacuums at roughly 0.3″Hg resolution, much better than traditional analog needle guages. The DRSA-1100 can be used in day-to-day servicing of moisture-free systems with confidence, as a good indicator of rough vacuum levels.

If you have a system that climbs in head pressure over a period of time, and you want to know how much it climbs in a certain period, the MAX/MIN pressure tracking feature in the the DRSA-1100 can tell you. But here is a trick I have used with the BTD-1000. Simply ‘ZERO’ the readout at stable operation, go do another service call and come back an hour or two later.

 

If the high pressure readout was 250 psig when you pressed “ZERO’, and it shows 35 psig when you return, then the pressure has climbed 35 psi while unattended. You can ZERO the unit at any reading and recieve a relative readout within the acceptable range. Should the pressure drop more then 15 psi, the display will flash as the DRSA thinks you have gone beyond a perfect vacuum! After using this trick, don’t forget to ZERO the analyzer again before you start the next job.