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Whole House Humidifier for Winter Comfort

whole house humidifier
Aprilaire whole house humidifier

Do you have a whole house humidifier?  If not, you may want to consider adding one to your heating system.  Using a forced air furnace in the winter has the unfortunate side effect of drying out the air. Using a humidifier can add back much needed moisture to your indoor environment!  

Advantages of a whole house humidifier include:  

  • Feel more comfortable.  Proper humidity level may help fight off colds, flu, and asthma symptoms. Your skin will feel less dry and itchy. You will reduce static electricity shocks, which your pets will appreciate!
  • Reduce heating bills.  Adding some humidity can help you feel warmer at lower temperatures.
  • Protect wood in your home such as floors, furniture, pianos, and string instruments such as guitars and violins.

Humidifiers do require occasional maintenance.  If you’re handy, you can do it yourself, but most of our customers choose to have us maintain their humidifiers when they do their seasonal tune ups. If you choose to do your humidifier maintenance yourself, be sure to first turn the humidifier off (on some models, this would be “Summer” mode), disconnect the electrical power to the HVAC system, and shut off the water supply to the humidifier.

The following is a list of common maintenance tasks to keep your humidifier running trouble free.

  1. Replace your water panel or pad as recommended.  This is usually once a heating season, but some models require twice a season changes.
  2. Turn off humidifier at end of the heating season.  Your air conditioner coil may ice up  if it is receiving humid air from the humidifier.  On some humidifier models, this may require turning off the bypass damper to shut off air flow.
  3. Turn off water supply.
  4. Clean water tray to remove mineral deposits annually.
  5. Check water feed tube for cracks, leaks.
  6. Make sure the drain line is free of mineral deposits or clogs.

Don’t spend another season living with dry air. Call KJ Thomas Mechanical at 303-435-8141 or contact us online to have a humidifier installed or maintained. 

KJ Thomas Mechanical Special Offers

KJ Thomas Mechanical currently has two special offers running through 1/31/18 to thank you for using us for your heating and air conditioning needs.  We appreciate your trust, repeat business, and referrals over the years.

Our first special offer is for annual routine furnace maintenance. If you want to make sure your furnace ready to keep you warm this winter, call for your $89 tune up.  Note that this price is good only for the first furnace in multi-furnace homes.  Additional furnaces would be tuned at the normal price.

The second special offer from KJ Thomas Mechanical  will interest you if you are considering a new air conditioner or furnace. From now through the end of January, purchase a Trane air conditioner and get a Trane furnace for 40% off the installed price. When you buy a furnace and air conditioner together, you are purchasing a ‘matched system”.  Your compressor (outdoor unit), coil, and furnace will be verified to work together with the greatest possible efficiency and reliability, resulting in a comfortable environment for you and your family.  If you mix components that are not matched in size and capacity,  your SEER (measure of cooling efficiency) could decline by 20% or more if your systems are not compatible.

You might wonder why this second offer of special pricing on air conditioner and furnace is only good for Trane equipment.  The reason is simple – Trane has built a reputation on quality for over 100 years.  James Trane opened a plumbing store in 1885, and started The Trane Company in 1913 with his son Reuben, who had just finished a mechanical engineering degree.  Trane is now an international company with top-rated commercial and residential products. I think the founders would be proud that in 2016, Trane was considered “America’s Most Trusted HVAC System” for the second year in a row (based upon surveying almost 18,000 residential.consumers).  

One of the reasons that “it’s hard to stop a Trane” is that Trane goes the extra mile to test its products.  Did you know that a compressor named “Snowball II” has been running non-stop since 2009 in a Trane Testing Facility?  It is encased in a block of ice to test the product under the most adverse conditions you can throw at a compressor.  And yes, there was a “Snowball I” compressor which ran almost 28 years, also completely iced up under the same lab conditions.

Additional evidence of quality components  in Trane compressors, which may vary according to model, include:  

  • sturdy polycarbonate top to stand up to the elements while looking great
  • sound insulation for quiet operation
  • rustproof base pan that won’t crack, rust, or warp
  • tough powder paint finish
  • galvanized steel louvers for air flow
  • 100% aluminum coils (better than copper-aluminum for preventing leaks and corrosion)

I would be happy to discuss your air conditioning needs with you if you want to take advantage of this special pricing.  And don’t wait to schedule your annual furnace maintenance.   Remember that these special offers are good through 1/31/2018.   Schedule today with KJ Thomas Mechanical either online, or by calling 303-435-8141. 

Repair or Replace Your Furnace?

Is it time to repair or replace your furnace? For most of us, this scenario happens sooner or later:  It’s cold outside, and it’s chilly inside too.  You check your thermostat, and discover that your furnace is not working properly.  Most of the time, I can diagnose the problem and repair it.  Sometimes, we will have a discussion about repairing the problem  versus replacing the furnace..  And occasionally,  I may advise you that the best, or even only, option is to replace.    What are the factors that play into this decision process and how can you know you made the right decision?

Let me address the second part of that question first.  How DO you know you made the right decision?  I think that’s where your trust in KJ Thomas Mechanical comes in.  As most of you know, I’ve been doing nothing but HVAC in Boulder County my entire adult life.  That’s over 30 years!  As the owner of a business, I rely on building ongoing relationships with my customers, and growing my business by referrals.  At the end of every transaction, I hope each customer understands the rationale behind my recommendation, which is offered always with short term and long term cost-effectiveness and safety in mind.  

So, what are some of the factors that enter into deciding whether to repair or replace a furnace? Here are some of the considerations:

Furnace Condition

If a furnace failed because of a bad part, and that part is discontinued by the manufacturer, a repair could be prohibitively expensive.  Discontinued parts can often be located as reconditioned or stockpiled, but they tend to cost a lot.  If a repair cost approaches $1000, repair might not be the best plan.  You must also factor in the cost of labor  when evaluating whether a repair makes sense.  In addition, after fixing this problem, are you likely to have other costly repairs in the future?

Sometimes older or unmaintained equipment is just plain unsafe.   If a furnace is leaking a significant amount of carbon monoxide due to a cracked heat exchanger, your HVAC service person will “red tag” it – i.e., shut it down as unsafe to operate.  I will give you an honest appraisal regarding whether the furnace is worth repairing.

Furnace Age

How much of a factor age is depends largely on the brand and model of the furnace.  The better brands simply last longer, as do the higher end models of a good brand.  The more cheaply built furnaces will need to be replaced sooner than a solidly built furnace.  But keep in mind that any poorly maintained furnace may show it’s age sooner than it should.

Furnace Efficiency

Much like air conditioners with their efficiency rated by SEER,  furnaces are rated by AFUE.  AFUE stands for Annual Fuel Utilization Efficiency, and basically measures how much fuel gets turned into heat (with the remainder being basically wasted).  The more efficient a furnace is, the more heat it can extract from the fuel.  For example, a 90% AFUE furnace means that  out of every 100 BTUs of fuel input into the system, you get 90 BTUs of heat output.  Furnaces are available within the range of 78-97% AFUE.   If you have an older model on the low range of efficiency that is experiencing a maintenance issue, you could consider replacing with a higher efficiency furnace. More efficient use of fuel means you will save on monthly gas bills.  Just be aware that you you might need to decrease the “size” (amount of heat a furnace outputs) if you increase efficiency to avoid oversizing the furnace for the amount of space you need to heat.  There are even calculators out there to help you see what kind of savings you might get with a more efficient furnace, such as this one.

Furnace Brand

You can do some research on the internet to read customer and professional reviews of different furnace brands to see where yours falls.  I install Trane furnaces because they are consistently at the top of the list for longevity, efficiency, and reliability.   Try to stay with a top-rated brand.  Remember, if you haven’t heard of it or it’s a low end consumer brand (that is, you can go to a big box store and buy it yourself), you should be cautious. Parts may not be readily available and they may be problematic.

Another thought to keep in mind as you consider furnace brands is that companies that sell less well-known and reputable brands may not be around to take care of you in the future.  Their technicians may not know how to size and install equipment properly, which could create headaches for you. It’s a good idea to make sure whoever you use to install a furnace is insured and has a minimum of 10 years experience by the owner.   Beware of meaningless claims such as“10 years combined experience” which could mean the company has 120 people with 1 month experience each!  We professionals develop an expertise in a product line as we stick with a well-known brand over the years (such as I have with Trane), and that expertise benefits you.  An HVAC company that frequently changes the brand of furnace it installs may be experiencing financial difficulties.

Furnace Warranty

The industry’s standard furnace warranty for an owner occupied residence is 10 years on parts with registration of the furnace with the manufacturer.  The warranty on labor from a company installing your furnace is usually 1 to 2 years. Again, choosing a reputable company ensures that they’ll be around to honor your warranties.

Finally, there is nothing like peace of mind!  Although no one can guarantee that your furnace won’t need emergency service, buying a reputable brand and keeping it maintained (including keeping a clean air filter installed) should decrease the chances that you will have to call for help.  KJ Thomas Mechanical has built its reputation on keeping you warm in the winter, and cool in the summer.  Call us at 303-435-8141 or contact us online.

Air Conditioning and Climate Change – the Future?

Air conditioning and climate change – how can future improvements help our environment? Efforts to reduce the impact of air conditioning on climate change continue with focus on new refrigerants, increased efficiency, and new technologies.  A recent National Geographic article caught my eye because it predicts that deadly heat waves could affect ¾ of the world’s population by the year 2100.  Deadly heat wave are not new  – we have seen them recently across the world.    For instance,  more than 70,000 people died in Europe in the 2003 heat wave, and many of the world’s large cities (including New York City) have experienced lethal heat. The very old and very young are most vulnerable to the effects of extreme heat.  The danger due to a small increase in temperature  is worse in humid environments.  While 1 degree Celsius seems like a small increase in global average temperature, it results in environments that are uncomfortable, and even unsafe, without air conditioning.  In places like California, Washington, and Oregon, where residential air conditioning use has historically not been widespread,  the number of households with some type of air conditioning (central or window units) has doubled since the 1990s.  

It’s clear that air conditioner use will continue to increase. As I mentioned in an earlier blog, the projection is for 1.6 billion new AC units to be in use by 2050 throughout the world. One area of focus for the air conditioning industry is to find more environmentally friendly replacements for our current refrigerants that deplete the ozone and/or emit greenhouse gases.  The ideal refrigerant will be safe, nonflammable, not deplete the ozone, not be a greenhouse gas, and will be cost effective to produce and use.  The search continues!

Another area of focus for the air conditioner industry is increased efficiency of air conditioning units.  Those 1.6 billion new AC units will require new coal burning, greenhouse gas emitting power plants to operate them.  Increasing efficiency will mean fewer plants will be built.  Currently,  air conditioner operation consumes about 14% of energy used in the United States. Most air conditioners built before 2006 have SEER ratings of 10 or lower, but newer units come with better ratings. (SEER stands for Seasonal Energy Efficiency Ratio, and measures cooling output in relation to electrical energy input to achieve that cooling.  The higher the SEER, the more efficient the unit is.) Trane’s most efficient air conditioner can achieve up to 22 SEER, with savings of 64% in energy cost.  It is expected that air conditioners will continue to increase in efficiency.

Research also continues into innovative cooling techniques.  Perhaps future air conditioners will use a completely different technology than today’s air conditioner, which removes heat from the air by blowing it across coils cooled by refrigerant. Researchers at the National Renewable Energy Lab (NREL) in Golden, CO, have working demonstrations of a new technology called DEVAP that uses desiccants to dry humid air which is then cooled through evaporation.  This process completely eliminates the use of conventional refrigerants.  Removing humidity is key to comfort, and that is something that today’s air conditioners don’t do very efficiently.  Savings of up to 30-80% less energy over today’s most-efficient air conditioners are possible because DEVAP only has to power small, efficient  fans and pumps. Likely, this new technology would be licensed to the HVAC  industry  with commercial products developed first, followed by products for homes.

As cooling season winds down in Boulder County, Colorado, there’s still a little bit of time to make sure your air conditioner is running well.  Remember that it is important to our environment to make sure your AC unit is running as efficiently as possible with no  leaks. We can squeeze in a few more tune ups before the fall chill hits.  This is also a great time to think about whether your furnace is ready for winter.  If you haven’t scheduled a furnace tune up yet, please schedule here or call 303-435-8141.

HFC Refrigerants and Climate Change

HFC refrigerants cylinder
HFC refrigerant cylinder

Hydrofluorocarbons, or HFC refrigerants, are the topic of this post, continuing the discussion of refrigerants and climate change.  In my last post,  I talked about how switching from CFCs to HCFCs, such as HCFC -R22, has reduced the ozone depletion caused by older refrigerants.  It is true that HCFCs aren’t as damaging to the ozone layer as CFCs, but they still have an ozone depleting effect and are in the final stage of being phased out.

Enter the 3rd generation refrigerants known as hydrofluorocarbons, or HFCs.  They consist of hydrogen, fluorine, and carbon.  Notice that, unlike CFCs and HCFCs,  HFC refrigerants do not contain chlorine and hence do not destroy the ozone layer.  However, like CFCs and HCFCs,  HFCs are a greenhouse gas.  HFC refrigerants are approximately 1000 times more potent than CO2 as a warming agent.  Though currently they comprise only a small percentage of greenhouse gas emissions, they will increase as air conditioning becomes more affordable and common in developing nations.  Some estimate that by the end of the century, HCF refrigerants could contribute to as much as 1 degree Celsius of warming.  If you have an air conditioner made after 2010, it probably uses HFC-410A as a coolant.

Because of increasing concern about global warming,  the Paris Climate Accord, reached in December 2015, was agreed upon by all but two countries.  The goal of this “gentleman’s agreement” is to reduce greenhouse gas emissions to 0 by 2050 and hold the increase in global temperature to 1.5 degrees Celsius.   The two nations who did not sign were Syria and Nicaragua.  Syria was in the middle of a civil war and couldn’t come to the table.  Nicaragua protested that the agreement was not tough enough to prevent warming.  Indeed, the target greenhouse gas reductions pledged by each nation is not legally binding.  President Obama pledged that the United States would reduce greenhouse gas emissions approximately 25 percent by 2025 using multiple means including clean power, reducing HFC refrigerants use and production, increasing energy efficiency of buildings and appliances, etc. In June 2017, President Trump withdrew the United States from the agreement.   However, as of July 2017, 350 mayors have formed the Climate Mayors and pledged to continue to follow or increase the Paris guidelines.   In fact, many of them have committed to the goal of 100% clean energy.  Boulder, for example,  is attempting to “divorce” Xcel Energy and create a municipal, clean energy electric utility.

The Kigali Amendment on October 15,  2016 to the Montreal Protocol specifically addresses HFC refrigerants, and stipulates a timeline for limiting production and use.  RIch developed countries in the European Union and the US will begin with a 10% reduction (from 2012 baseline) in the use and production of HFCs in 2019 down to by 85% by 2036. Developing countries have a more lenient timeline.  Reduction will avoid up to .5 degree Celsius of warming by the end of the century.   Note that the US has not ratified the Kigali treaty yet (and it’s fate would be uncertain under the new administration),  but indications are that movement will continue in the direction of implementing the phasedown, whether legally required or not.

Refrigerant manufacturers are working hard to develop the next generation of refrigerants to address the warming issues with HFCs.  Efforts are largely focused on hydrofluoroolefins, or HFOs.  These break down in the atmosphere in just days, so may have a lower global warming potential, but still are  typically from 160-600 times more potent than Co2.  In addition, HFOs tend to be either more flammable or toxic than HFCs.  Another possible refrigerant to look at using happens to be an HFC, HFC-R32, which has a Global Warming Potential of 677 which is much less than that of HFC-410A’s 2088. Propane, ammonia, and carbon dioxide also have potential for some cooling applications. What does this mean for you?  Your residential AC system will continue to use 410A for the foreseeable future.  If you have an older system that uses R22 and you face a significant repair, you may need to upgrade to a new system.  Just as has happened with R22, supplies of 410A will begin to decrease when the phasedown starts in 2019, and price will increase as the phasedown accelerates.  Research and development efforts will continue to identify coolants that are more environmentally friendly.   The industry may move toward a refrigerant which can be used in existing systems.

Meanwhile, you can do your part to limit greenhouse gas emissions by making sure that your equipment is running at peak efficiency.  Ask your HVAC technician to repair any leaks before refilling or topping off.  In a closed system such as an air conditioner, the only reason for low refrigerant is a leak.  Make sur your HVAC tech has the EPA 608 certification required to handle refrigerants.  Consider  asking to see their certification card.  Make sure your HVAC tech recovers and recycles any old coolant – it is illegal to just “release” it into the environment.   

Another aspect of climate change and air conditioning unrelated to the type of refrigerant used is the effect of increasing the efficiency of air conditioners, thus reducing the demand for coal-fired power plants which emit the greenhouse gas CO2.  But this is a topic for another post.  Meanwhile, please let us know if KJ Thomas Mechanical can help you with any HVAC needs.  Contact us here or call 303-435-8141.

CFC and HCFC Refrigerants and Climate Change

Refrigerant HCFC-R22, also known as Freon 22
Refrigerant HCFC-R22, also known as Freon 22

My last blog post mentioned  that air conditioning refrigerants,  such as CFCs and HCFCs,  play a role in climate change.   Refrigerants, also known as coolants, have evolved over the last 90 years and will continue to change as part of the drive to lessen their impact on the environment.

 Did you ever wonder what type of coolant your air conditioner uses?  You can easily find out by checking the nameplate on your outside unit. That nameplate tell you, among other data, the type of refrigerant your unit uses.  After reading this and the next post, you will know how “evolved”  that coolant is! Recall that in my previous post, I mentioned that the first generation refrigerants, including ammonia,  propane, and sulphur dioxide, were toxic and flammable.  In this post, you’ll find out about chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), the safer second generation refrigerants.

CFC Refrigerants

Recall that CFCs were invented in 1928 and were widely known by the DuPont trade name Freon.  CFC-R12 (Freon-12) was widely used  in refrigerators, inhalers, and aerosol spray cans.  CFCs were not widely used in air conditioning systems, but are worth talking about here to understand their effect on the environment.

Around 1970, scientists realized that CFCs deplete the “good” ozone in the earth’s upper atmosphere.  The layer containing ozone extends 6 to 30 miles above the earth, and protects living things from the sun’s harmful ultraviolet radiation. Exposure to increased UV radiation has caused an increase in skin cancer and cataracts, damaged crops, and affected the foundation of the ocean food chain by damaging phytoplankton.  When CFCs, which  are made of chlorine, fluorine, and carbon, break down over time due to exposure to UV radiation, they release chlorine atoms which react with the ozone molecule to destroy it. One chlorine atom can destroy 100,000 ozone molecules! CFCs are responsible for the big hole in the ozone layer over Antarctica discovered in 1985.

To make matters worse,  CFCs also are a “greenhouse gas”.  Greenhouse gases act like an insulating blanket over the earth, trapping heat instead of letting it escape into space.  Even when present in very low atmospheric concentrations, they cause a great deal of damage  because they have a very long lifetime before breaking down in the atmosphere.  For example, CFC-R12 has a lifetime of approximately 100 years, while other CFCs can last from 45 to 1700 years.

One standard for measuring and comparing greenhouse gases is the Global Warming Potential (GWP).  It quantifies the amount of heat a gas traps, and how long the effect lasts depending on the lifetime of the gas.  Every gas is compared to the greenhouse gas carbon dioxide,  which is arbitrarily assigned a GWP = 1.  Using the latest assessment data from 2014,  CFC R12 has a GWP of 10,200.  That is, it is over 10,000 times worse for the climate than carbon dioxide!  

To deal with the global problem posed by CFCs, The Montreal Protocol of 1987 was signed by 197 nations to phase out the production of CFCs by 1995. Since then, only CFCs recycled from old equipment has been available.  

HCFC Refrigerants

HCFCs then became the go-to refrigerants as alternatives to banned CFCs.  HCFCs contain chlorine, fluorine, and carbon (just like CFC), but also contain a hydrogen atom which decreases their stability and gives them a shorter lifetime in the atmosphere.  They mostly break down before they reach the ozone. Like CFCs,  HCFCS may be referred as “Freon”.

 HCFC-R22 (also known as  Freon 22 and R22) has been the standard for use in residential air conditioners starting in the 1960s, when new houses often came with AC, through the mid 1990s with use decreasing through 2010.  Although HCFCs are much less damaging to the ozone than CFCs, they are still powerful greenhouse gases (though not as bad as CFCs). For example, R22 has a GWP of 1760, almost 2000 times worse than CO2.

As a result of environmental concerns, the Montreal Protocol was amended to also phase out specifically HCFC-R22 by 2020, and all HCFCs by 2030. Production and import of R22 was banned on January 1, 2010, except to service and maintain existing equipment.   R22 air conditioners were banned from production by the EPA  as well starting in 2010 (except for an interesting loophole recently closed that allowed manufacturers to produce and ship units “dry” for filling with R22 onsite).  Production and import of R22 will be decreased gradually to zero by 2020, at which point equipment can only be serviced with recycled or stockpiled HCFC-R22.

What does this mean for you as a consumer if you have an AC uses HCFC-R22? You can still recharge your equipment (after fixing any leaks!) with R22 as needed to maintain it from recycled or stockpiled supplies.  Unfortunately, not a lot of R22 gets recycled.  So as supplies decrease, prices will continue to rise.  Currently, R22 is at least 5 times more expensive than more modern and preferred coolants, and  even that may seem inexpensive in the future. Another option may be to retrofit your R22 unit to use a more environmentally friendly coolant MO99 (also known as HCF-R438a).   If you need a major service, it might be time to replace your older equipment with a new system that is more energy efficient and uses a more environmentally friendly and less expensive coolant. We’ll talk about these refrigerants in the next post,

The good news?  The hole over Antarctica is starting to heal, and predictions are that it can be completely healed by 2050 if further damage to it can be averted.  There are more environmentally friendly refrigerants available today.  There are even developing technologies that hold promise to cool without the use of refrigerants!  Stay tuned!  And as always, call KJ Thomas Mechanical at 303-435-8141 if you need heating and air conditioning installation or service. 

Air Conditioning and Climate Change



Air conditioning and climate change goals don't have to be incompatible.
Air conditioning makes life bearable in Hong Kong’s residential tower

The relationship between air conditioning and climate change is important to understand. The New York Times recently published an article about how improving the efficiency of air conditioners and using more environmentally friendly refrigerants (aka coolants) can be part of the solution to climate change goals.  As summer heats up and we turn on our air conditioners,  you might wonder about the impact of air conditioning on the environment.  

You’re not alone.  International, national, and local efforts in Colorado, including  Boulder County, continue to focus on

Air conditioning is here to stay.  In fact, it is just now becoming affordable to ordinary people in countries such as India, Brazil, Indonesia, and China.   1.6 billion new air conditioners are expected to be installed by 2050.  I’m planning a few blogs to address topics related to air conditioning and climate change to help you understand where the air conditioning industry has been, where it is, and where it’s going.  Being an informed air conditioner owner will help you be part of the solution. We all need to help make sure we “get it right”!

The first few posts will focus on refrigerants, which are the gas in your air conditioning system that transfers heat from the warm inside air and releases it outside.   It can be confusing to figure out which are banned, which are still OK to use in some situations, what the best refrigerant is today, and what is likely to be used in the future.  Treaties and agreements signed by almost all nations,that are in various stages of ratification by the United States, as well as EPA regulations impact the condenser in your backyard and the technician who services it. I’ll try to sort that out for you too.

Where would we be without refrigerant?  We depend on it to keep comfortable in the summer in our cars, homes, and places of work and recreation.  Coolant helped pave the way for modern skyscrapers made of fixed glass panes and steel, and helped fuel population booms in hot cities such as Houston.   Refrigerant also freed us from iceboxes, although there are still people around who fondly remember following the iceman’s cart in order to pick up refreshing chips of ice. The early, first generation refrigerants were toxic and flammable gasses such ammonia, sulphur dioxide, and propane.  The invention by Thomas Midgley of the first chlorofluorocarbon (CFC) refrigerant in 1928 ushered in the second generation of stable and non-toxic refrigerants.

Check back here on my blog for more information on air conditioning and climate change.  In the next post, you will learn about the characteristics and availability of the the refrigerants known as CFCs and HCFCs.   In the meantime, if you have any concerns about whether your air conditioner is operating as efficiently as possible, call KJ Thomas Mechanical at 303-435-8141 or schedule online.


Air Conditioner Ice Buildup

Air conditioner ice buildup

If you have air conditioner ice buildup on your evaporator coil or compressor unit, you may be wondering why this happens.  Recall from my last blog that your central air consists of the  evaporator coil and the compressor.  The evaporator coil is the part of your “split” air conditioner that is attached to your furnace and cools warm inside air.  In the summer, warm air in the house is “returned” to the furnace via the cold air return.  The furnace blower motor blows that warm air over the evaporator coil which contains coolant.  This process transfers the heat in the air into the coolant, and then the cooled air is forced through your house’s duct work.  The compressor is the unit sitting on a pad outside.  It sucks in the warmed coolant from the house and compresses it to make it hotter.  Then a fan blows air over the condenser fins to transfer the heat in the coolant to the surrounding outside air.

Sometimes, something goes wrong and the coil, or even the compressor, can end up resembling an iceberg!  Most coils are housed inside a case, so you might not see an ice build up until it becomes severe.  But you will  probably notice that your air is not as cool as it once was.

Ice buildup is a sign that something has gone wrong in the AC cycle which has caused the evaporator coils to become too cold.  When the coils become too cold, the moisture in the relatively warm air in the vicinity of the coils condenses onto the coils and freezes. A side effect of frozen or frosty evaporator coils is that your compressor runs at a hotter temperature than it should and may burn out.  Or, it may ice up too!

There are many reasons for air conditioner ice buildup in the evaporator coil and/or compressor.  Common causes of evaporator coils becoming too cold and icing up include:

  1. Blower motor not working.  If the blower motor isn’t blowing warm house air across the evaporator coil, the coolant in the coil never warms but instead gets colder and colder.  
  2. Low coolant level. If the coolant level is low (probably due to a leak or under filling), when it expands as part of the AC cycle when it enters the evaporator coil, it cools off too much.
  3. Overcharged unit.  If there’s too much coolant it the system, it can also cause ice (as well as ruin the compressor).
  4. Dirty air filter. A dirty air filter decreases the airflow across the coil,which basically has the same effect as blower motor not working. )
  5. Running the system when it is too cold (below 60 degrees or so) outside.  Your air conditioner just wasn’t built for that!
  6. Restriction in the coil
  7. Faulty metering device (aka expansion valve).  This controls the amount of coolant coming into the evaporator coils.
  8. Improper sizing of equipment.  If your system is too large or too small (i.e. the “tonnage” of your system, or how much heat it can remove in an hour), this negatively impacts its operation.

What should you do if you notice air conditioner ice buildup?  First, turn off your air conditioner and let the ice melt away.  Then, check for dirty air filters,  blockages in the ducting, or debris buildup in and around the compressor.  If none of those are causing the problem, then it might be time to have KJ Thomas Mechanical out to diagnose the problem. We have over 30 years of experience installing and servicing heating and air conditioning systems and can help you keep your system running well.  Call us at 303-453-8141, or schedule online.

Tankless Water Heater Maintenance

A tankless water heater might be the solution to your hot water problems.  Large tank-based systems can’t solve every problem, such as teen-agers who take long showers, or tight crawl spaces that can’t accommodate a standard tank.  If you’ve already made the switch to a tankless system, you know the advantages:  endless hot water, lower energy bills, repairable components, installable in attics or crawlspaces.  

You might wonder how to maintain a tankless water heater.  Some people think that no maintenance is required.  My experience tells me that is not true.  Regular maintenance can prevent the need for unexpected repairs, satisfy terms of  your warranty, and keep that hot water coming when you need it.

This tankless water heater is getting it's annual service by KJ Thomas Mechanical.
This tankless water heater is getting its annual service by KJ Thomas Mechanical.

The common problem with any water storage system is mineral deposits, typically lime and calcium.  When minerals build up on the heat exchanger, the system can stop functioning.  And worse, damage to the system from mineral buildup may void your warranty.

The solution?  Keep an eye on your tankless water heater.  If you see an error code that indicates mineral buildup, it’s time to flush the system.  You can do that yourself if you’re handy, or you can call KJ Thomas Mechanical.  We will circulate a  special tankless heater cleaning solution using a bucket and external pump until unit is descaled, then rinse it out completely.

Cleaning solution is murky brown due to mineral deposits in tankless water heater
Tankless water heater cleaning solution has turned murky brown with flushed mineral deposits.

  Another tip?  Keep the area around the exhaust vent free of debris, ice, and snow.  A properly maintained tankless water heater should give you many years of service.  Call KJ Thomas Mechanical for your annual service, or contact us online.

Air Conditioner Tune Up

Scheduling an air conditioner tune up is a good way to keep it running smoothly and efficiently, avoid having it fail during the heat of summer, and prevent more costly maintenance issues.   After you read this post (and the previous post on how your air conditioner works), you should have an idea of what happens during a tune up.

 Air conditioner tune up basics
  • Someone needs to be home to provide access to the furnace area.
  • We often have a special pre-season tune up price posted on our website or included in our seasonal newsletter.  Or, you can call 303-435-8141 to find out the current price.
  • It’s best to schedule the tune up before the summer heat hits, just to make sure your air conditioner is running properly.
  • The outside temperature needs to be at least 60 degrees to do a tune up.  If it’s colder, it’s difficult to tell whether the air conditioner is cooling the air, or if Mother Nature is! Once in a while, she fools us with some cooler temperatures  and we may need to reschedule with you.
Air conditioner tune up checklist

What can you expect KJ Thomas Mechanical to do to make  certain your air conditioner is running well after the tune up?  The answer is, whatever it takes!  In one case, that required removing a wasp nest from the AC control box!

Air conditioner hook up
Wasps built a large nest in this air conditioner control box









Air conditioner electrical box
Thanks to Karl, this air conditioner control box is no longer a home for wasps.

A typical air conditioner tune up involves checking the unit outside the house, at well as the components inside.

Air Conditioner tune-up Longmont, CO
Karl cleans and checks the outside AC unit

Outside, we will:

  • Clean condenser  coils and fins
  • Check electrical connections and tighten
  • Check coolant level
  • Inspect components in control box
  • Check tubing for clogs and leaks
  • Check fan motor operation

Inside, we will:

  • Check furnace filter
  • Check drain lines for clogs
  • Check duct work for leaks
  • Check blower motor operation

Schedule your tune up

The summer heat is due to arrive this week, so make sure you’re ready to stay cool.  Call KJ Thomas Mechanical  at 303-435-8141 to schedule your annual tune up.  You can also use our convenient online scheduler.