Thermal Degradation in HVAC systems

CLEAN COILS?

Dirt sticks to metal coils (heat exchangers).

Dirt blocks heat from moving through metal.

SOLUTION:
Remove the dirt.
Less Energy Loss

Move more heat.
RUN LESS.

A similar problem exists on the inside of the coil.
It’s a very simple problem:

Oil sticks to metal.

Oil blocks heat from moving through metal.

Ever wonder why that old system won’t keep up?

SOLUTION:
Remove the oil.
No Energy Loss

Move more heat.
RUN LESS.

Don’t take our word for it…

A.S.H.R.A.E.

A.S.H.R.A.E. (American Society of Heating, Refrigeration, and Air-conditioning Engineers) has studied this problem. A.S.H.R.A.E. estimates that this thermal barrier accounts for up to a 30% reduction in efficiency within the first 5 years of the equipments life. As studied by A.S.H.R.A.E., during the refrigerant compression process, oil migrates from the compressor to the coil system contaminating the metals that transfer heat. Compressors that use oil for lubrication do not prevent oil from fouling the coil system. Even the smallest amount of oil in the coil system creates a film or coating that will hinder heat transfer reducing the efficiency of the unit.
  • ASHRAE Study RP-751, “Effects of Oil on Boiling of Replacement Refrigerants Flowing Normal to a Tube Bundle-Part I: R-123, Robert A. Tatara, Ph.D., Parviz Payvar, Ph.D.,P.E.
  • ASHRAE Study RP-751, “Effects of Oil on Boiling of Replacement Refrigerants Flowing Normal to a Tube Bundle-Part II: R-134, Robert A. Tatara, Ph.D., Parviz Payvar, Ph.D.,P.E.
  • ASHRAE Transactions 1986, Vol 92, Part 2, “The Effect of Oil Contamination on the Nucleate Pool-Boiling Performance of R-114 From A Porous-Coated Surface”, A.S. Wanniarachchi, Ph.D., P.J. Marto, Ph. D., J.T. Reilly
  • 1986 ASHRAE Handbook I-P Edition, Refrigeration Systems and Applications, Chapter 1.8, “Oil Return Equipment”
  • 1998 ASHRAE Handbook I-P Edition, Refrigeration Systems and Applications
  • Chapter 2.9-2.11, “Oil Management in Refrigerant Lines” AND 7.11, “Effects of Partial Miscibility in Refrigerant Systems”
  • 2010 ASHRAE Handbook I-P Edition, Refrigeration Systems and Applications, Chapter 12.17, “Refrigeration Lubricant Requirements”

HVAC/R Original Equipment Manufacturers (OEM)

All HVAC manufacturers know their equipment performance degrades once in service because of oil contamination in the heat exchangers. Most often they will not admit it and adamantly deny the issue. If you ask OEM employees and service partners they will usually deny the problem exists. The industry does not want you the consumer to know that their equipment degrades in performance causing up to 30% more kWh usage in just a few years. That little efficiency sticker and EER rating on your equipment is only true when it is new, not after it is installed and in service.

OEM’s have a solution for thermal degradation

  • Buy new equipment.

Skeptical? Read Trane’s patent for oil-less chiller systems. They spent a vast resources designing a mechanical way around the oil problem and patented it.  In their most recent product brochures they omit oil being a problem (initial brochures contained this information), perhaps they do not want you to understand the issue.

Section: SUMMARY OF THE INVENTION

It is a further object of the present invention to eliminate oil migration problems and the need to return oil from chiller system heat exchangers to the chiller’s compressor as a result of the migration of oil to those heat exchangers during chiller operation.

It is a still further object of the present invention to, by the elimination of oil migration, increase chiller system efficiency by eliminating the oil-coating of heat exchange surfaces in the chiller system’s heat exchangers and the resulting diminishment of the heat transfer process that results therefrom.

Trane Patent 6564560, Patent Link
Section: BACKGROUND OF THE INVENTION

Elimination of oil as a lubricant in a large tonnage centrifugal refrigeration chiller system and the use of the refrigerant which comprises the chiller’s working fluid for that purpose offers potentially tremendous advantages. Among those advantages are: elimination of many chiller failure modes associated with oilbased chiller lubrication systems; elimination of so-called oil migration problems associated with the mixing of oil and refrigerant in such chiller systems; enhancement of overall system efficiency by eliminating the oil-coating of heat exchange surfaces that results from the entrainment of oil in system refrigerant and the carrying of that entrained oil into a chiller’s heat exchangers; elimination of what is viewed as an environmentally unfriendly material (oil) from the chiller system as well as the problems and costs associated with the handling and disposal thereof; and, elimination of a great number of expensive and relatively complex components associated with chiller lubrication systems as well as the control and maintenance costs associated therewith.

Trane Patent 6564560, Patent Link

Now you know.

Simple illustration of how refrigerant and oil create a problem:

When refrigerant is compressed to a liquid (liquid phase ) lubrication oil mixes with the liquid refigerant. There is no way to mechanically prevent this from occurring. Trace amounts of oil are then pushed into the heat exchangers with the mixture of liquid refrigerant and oil. This oil creates a thermal barrier on the internal walls of the heat exchangers.

Thermal Degradation is caused by oil deposits and contaminants in the heat exchangers.

Contamination Occurs: (this happens in all types of compressors that use oil for lubrication, this is a simple example of a reciprocating compressor.)
A. Oil lubricates the compressor’s cylinder, rings and piston to prevent burnout and excessive heat from the moving mechanical parts.
B. The oil mixes with the refrigerant.
C. The refrigerant is pushed through the coil system which also contains some of the lubricating oil mixed in.
D. Oil then contaminates the coil.
E. This oil slows the refrigerant flow making the compressor work harder because of added laminar friction.
F. Oil forms a very thin coating creating a barrier to heat transfer.
G. This happens continuously, contaminating the entire coil over time.

Substantial Impact for the Enterprise

Left unfixed, the HVAC systems consume more energy than they should. Extrapolated across your inventory of equipment this adds up to a significant waste in money and energy resources. For most commercial applications, office space & comfort cooling a good savings estimate is 8-15% of your total kWh consumption. For industrial and data center applications it depends on the ratio of HVAC(R) to other plug load.

Contact us for an analysis of what we can save you

THE FIX

0%
Ignore it.
Waste up to 15% kWh of your total power consumption. Power company loves you.
Return on Investment is 0.
100%
Dismantle and acid wash each system,
every year.

Your service company loves you.
Return on Investment is 0.
100%
Replace all HVAC(R) equipment
every 5 years.

Your HVAC manufacture will love you.
Return on Investment is 0.

 Use PermaFrost NMR®

PermaFrost NMR® Solution

PermaFrost NMR® is the only industry proven nano-science chemical that permanently restores SEER, COP and DELTA T through thermodynamic metal enhancement.

Powertron Global’s PermaFrost NMR® product line is a thermal nano-surface coating. PermaFrost NMR® coats the metal at the atomic level displacing the non-thermo-conductive oil on the internal surfaces, increasing its volumetric heat transfer properties and protecting against corrosion. The insulating oil  is displaced with a superior conductive material which restores and accelerates heat transfer. The system moves heat efficiently reducing the kilowatt consumption and runtime of the HVAC system significantly. It is a one time installation and will last for the life of the unit.

Use of PermaFrost NMR® will not void your HVAC(R) warranty.

Image of a cut cross section of coil from a 35 year old 4 ton AC
that was treated with PermaFrost NMR®.

What PermaFrost NMR® Does

Increase the thermo-conductive properties of the coil system through nanomagnetic filming and electron transfer enhancement.
Regain the lost efficiency caused by oil migration by displacing the barrier of conductive oil.
The unit moves more heat, reaches a thermostat set-point faster and runs less consuming less kWh.
SEE THE PRODUCT LINE