Martin Mechanical Kansas City
  • Home
  • Services
    • HVAC/Chillers
    • Boilers/Burners
    • Industrial Piping
    • VRV/VRF
    • Service
  • Education
    • Training Events
    • Blog
  • Contact
  • About
    • Team
    • Projects
    • Gallery

Martin Mechanical Speaks Out

1/19/2019

0 Comments

 
Since 1820, Missouri citizens—from early lobbyists and business owners to minimum wage workers--have been writing, calling, and now emailing their concerns to state representatives in Jefferson City. However, with the ease of 21st-century technology at our fingertips, the face-to-face political visit has fallen by the wayside. We decided to take back this civic responsibility at Martin Mechanical. On Tuesday, January 15th, Missouri contractors joined forces and went straight to the source in Jefferson City, meeting with six top-tier state officials across party lines. We believe the freedom to make our voice heard is the greatest privilege we have as Americans, especially at the state level of government.
Twelve contractors and MCA members, hailing from Kansas City all the way to St. Louis, convened at the State Capitol to discuss bills from the past session and potential upcoming voting concerns. We each brought our own individual views to the conversation, but as a group of successful, intelligent men and women with a common goal, we were able to exert more pressure and generate a diverse range of solutions. 
We prepared for the trip by reviewing all submitted legislation from the most recent session. We located and focused our energy on the three bills that most significantly impact our companies, employees, and other Missourians working day-to-day to make ends meet:
  • Bill 91: The Prompt Pay Act (Mandating payment to contractors within 30 days)
  • Bill 120: STEM for Contractors (Offering up to $10,000 in scholarships for contractors hiring interns and recent graduates)
  • Bill 326: Statewide Mechanical Licensure (Streamlining the process for contractors to obtain a single qualifying license for all mechanical work across the state)
We then spent the afternoon walking the halls of the Capitol and meeting with carefully-selected individuals who have the power to make a difference after listening to our professional expertise. As in any negotiation, words mean something—and words delivered directly, in-person and face-to-face, have the most power. Drawing on our experience as company owners, presidents, and managers alike, we understood the necessity of making a clear and succinct case for our needs, focusing on this goal during our 5-10 minutes of fame with representatives. Our message was well-received (as well as can be expected in the complicated arena of politics), and the intimidation factor of thirteen united men and women in suits will always be more convincing than a party of one.
This experience reminds us that there is something to be said for working toward a greater cause in our industry, rather than just the lowest bid or equipment sale. Kansas City and St. Louis markets can be highly competitive, but in this case, community prevailed as we all worked together on behalf of our employees. We truly enjoyed the trip and the company, and we’d like to offer a big thanks to the representatives who listened to the MCA and Missouri contractors, each representing over 5,000 employees statewide. Reminding our representatives of the importance of fair and ethical labor practices—early, often, and repeatedly—will help keep our state and Constitution strong. 
​
0 Comments

Refrigeration 101

1/8/2019

2 Comments

 
Picture
​Refrigeration components:
  • Compressor- Reciprocating, scroll, rotary, screw, centrifugal
  • Condenser- Air Cooled static, Air cooled forced air, Water cooled, Evaporative, Tube in tube, Shell and tube, Brazed plate, Plate and frame
  • Metering device- Capillary tube, Thermostatic expansion valve, Electronic expansion valve,
  • Evaporator- Fin and Tube static, Fin and tube Forced air, Brazed plate, Shell and tube, Flooded shell
  • Receiver (not required)
  • Accumulator (not required)
  • Oil Separator (not required)
  • Oil reservoir (not required)
 
Compressors:
Hermetic- Can be reciprocating, scroll and rotary compressor(s)
Semi-hermetic- Can be reciprocating, rotary or rotary screw, centrifugal
Open Drive- Can be reciprocating, centrifugal
Compression Ratio: How and why it is so important?
Our goal as mechanics is to achieve “the work” with the lowest compression ration
Compression ratio: Air Conditioning
Discharge pressure + 1 atmosphere (roughly 15 psi)                            300+15=315
           Suction pressure + 1 atmosphere                                                    72+15=87
                     = Compression ratio                                                           =3.62 Comp Ratio
Compression ratio: Low Temp Refrigeration
Discharge pressure + 1 atmosphere                                                         300+15=315
Suction pressure + 1 atmosphere                                                                  7+15=22
= Compression ratio                                                                                =14.31 Comp ratio
 
Why is this important? It is a metric to use to see actual throughput of your work. If you are NOT using compression ratio’s as comparison of work, you should be. What other tools should you be using?
  • Amp draw
  • Subcooling
  • Superheat
  • Condenser approach
  • Evaporator approach
Picture
​Always log your starting point:
  • OAT- Entering air of condenser
  • Leaving air of condenser
  • Condenser Delta T
  • Compressor amp draw
  • Nameplate amp draw
  • Evaporator entering air
  • Evaporator leaving air
  • Evaporator Delta T
  • Discharge pressure (or liquid if that is the only port you have)
  • Suction pressure
  • Superheat
  • Subcooling
  • Drop leg pressure and temperature (Condensing unit with a receiver)
Continue to measure above points as you make system adjustments. DON’T GUESS use DATA!
Picture
Picture
​Find the answer:
You have a low temp rack (R-22 with a C/I of 12psig and a C/O of 4 psig)
That rack is fitted with a 2-stage mechanical sub cooler and you are delivering 40 liquid temperature liquid to the 5-door frozen case. You have an expansion valve rated a 1 ton of capacitance, what is its corrected capacity?
Mechanical subcooling on a Package RTU?
Mechanical subcooling on a water-cooled chiller?
Mechanical subcooling on your home split system? HUH?
​Refrigeration Specialties
Filter dryers-
Picture
Picture
Picture
2 Comments

Education

1/7/2019

0 Comments

 
Sectional Steam Boilers-Vacuum Pump, Tank, and Trap survey replacements
We diagnosed a boiler issue a couple weeks ago for a customer in downtown Kansas City, as is the time of the year, boiler issues are critical, so a quick and correct assessment is needed. Our President, Jim Rogers, and a new PM went to attack this customer critical issue and came up with the solution below:
When a customer called and reported a boiler room issue, we came running. The steam sectional boiler is an ancient art quickly being replaced by hot water and electric boilers in new construction. However, downtown Kansas City is redeveloping many of its historic buildings to fuel the reemergence of its urban lifestyle and business hub. As this trend continues, and as space for new buildings remains minimal (and expensive), the steam boilers of the past will continue to serve as the single heat source for older buildings. Many mechanical contractors lack the knowledge or experience to manage these issues. At Martin, we continue to dedicate our time and effort to learning both new and old techniques. We pride ourselves on repairing and maintaining historic boilers while also sizing, updating, and installing contemporary boiler systems designed for the twenty-first century.
This is a common issue building owners face when running an old steam boiler, in a vacuum style system, with changing and untrained personnel, this style of systems will never be properly diagnosed or properly fixed. Martin Mechanical had the extensive knowledge and properly trained employees who saw the issues and were able to correctly fix each part of the problem.
At this specific building, originally built in 1909 and currently running a 1980s Smithville boiler, we faced a rotting vacuum and feed water tank. To make the situation worse, the lack of system maintenance and past “quick fixes” led to an inefficient workload and strain on the boiler and pumps. After a few minutes of examining the equipment and piping, as well as asking the maintenance staff about run times and upkeep, we realized the built-to-run vacuum system was operating incorrectly: running unnecessary loads on the system, wasting thousands of gallons of water, and draining costly utilities due to the incorrect sizing of pumps and traps. By replacing the rotted tanks for proper sizing, reconfiguring the piping layout, and bringing the low-pressure steam boiler back into the proper vacuum, we found a solution to run the system efficiently and effectively. As a result of this fix, the vacuum pump pulls air from the system, allowing for a smoother, more rapid heat build-up.
 
Refrigeration 101 – w/video and Fill in the blank matching test
Last week we held our monthly class at the Martin offices in our training room. This months focus was on the refrigeration cycle, parts, and components which make up the system for a building. Attached below are the slides from the class, a link to our youtube channel for the video, and a short matching “fill-in-the-blank” quiz over common parts and materials installed in a refrigeration system. Much was discussed outside the pictures, captions, and prompts on the power point, but some of the best highlights of the 2.5hour long training from our in-house expert, John Maske, follow;
“R410a refrigerant, because of its near Azeotropic properties, is the best balance of both worlds for temperatures, with both gases and liquids…”
“Parallel Metering Devices, will help a system fight against Room temperatures…”
“The thermostatic expansion valve (TEV) controls the flow of liquid refrigerant entering the direct expansion (DX) evaporator by maintaining a constant superheat of the refrigerant vapor at the outlet of the evaporator…”
Compression Ratios: Air Conditioning and Low Temp Refrigeration
Discharge pressure + 1 atmosphere (aka 14.7 or 15psi basically)/Suction pressure + 1 atmosphere
“Higher Pressures = Best possible heat transfer”
“…A good stewart of customers would do yearly tube analysis on chillers, via pneumatic probe and dry run, prevent maintenance is good maintenance…”
 
Refrigeration 101 specialties Quiz (link with above post)
Refrigeration Specialties
Name the following specialty items    
(Answers: Top down, left to right)
  1. Filter Dryer
  2. Filter Dryer
  3. Oil Filter (Suction side only)
  4. Oil Float
  5. Hot Gas Bypass valve
  6. Evaporator pressure regulator (EPR)
  7. Liquid pressure valve
  8. Pressure Regulator (outlet side-full stroke side of regrigerant)
  9. Electronic Expansion Valve (EEV)
  10. Electronic Pressure Relief Valve (EPR)
  11. Head Master valve
  12. Oil Separator
  13. Oil Reservoir
  14. Water Regulator (outlet side of condenser to watch head pressure)
  15. Condenser tubes
  16. Shell – Tube Chiller
  17. Head Pressure Control
  18. Transducer 
0 Comments

    Martin Mechanical

    Archives

    January 2019

    Categories

    All

    RSS Feed

Contact

Martin Mechanical Inc.
​1419 E 19th Street

Kansas City, MO 64108

816.842.2900

Services

​- HVAC
- Chillers
- Boilers/Burners
- Industrial Piping
- VRV/VRF

Contact Us

    Subscribe Today!

Submit
Copyright © Martin Mechanical Inc. All rights reserved.
  • Home
  • Services
    • HVAC/Chillers
    • Boilers/Burners
    • Industrial Piping
    • VRV/VRF
    • Service
  • Education
    • Training Events
    • Blog
  • Contact
  • About
    • Team
    • Projects
    • Gallery