Author: Kevin

In our last post, we talked about some of the things to consider when calculating the peak cooling capacity for an add-on space. In this post, we’ll discuss some options for providing cooling to your add-on space.

Window air conditioner

This option is usually the first one homeowners dismiss, and with good reason. Although it may be cheap to install, it is very costly to run, unsightly especially if you can easily see it from the front of your house – and noisy. If you are cooling a basement space, you might not even have a window you can use! Assuming your add-on space is conducive to using a window air-conditioner, you’re still left with a heating dilemma, and more than likely will need to use either a portable room heater or add-on baseboard heat (see our post “5 Ways to Heat Local Spaces”).

Tying into your existing central HVAC system

Often, adding ductwork to your add-on space in order to connect it to your existing central HVAC system can be difficult or impossible, but this can be a great solution for providing both heat and air-conditioning. But, even if you can do it, doesn’t mean you should. Here are some things to consider:

• Is your current HVAC system rated to carry the additional load or will adding the additional space mean your existing system will now be under-sized, making your whole house uncomfortable?
• Will the add-on space need to be a separate zone, so you can control the thermostat independently of the rest of the house? This is often the case when your add-on space is in an area with vastly different needs from the rest of the house: a room that is only used occasionally, a room that is underground, or has lots of windows (a sunroom), or a room with special equipment or machinery.

To see if tying into your current HVAC system is a viable option, you’ll need to consult an HVAC professional.

Ductless Mini-Split an Ideal Solution

A ductless mini-split is often an ideal solution for most homeowners because it by-passes the expense of ductwork and is extremely efficient to install and operate. Mini-splits are available as air-conditioning only units, or as a heat pump offering both heating and cooling. Here are just some of the reasons why a mini-split might be a solution for your add-on space:

• Ease of Installation: It only requires access to an electrical outlet and a single small hole in the wall (about 3″ diameter, to accommodate refrigerant lines) for the indoor wall-mounted unit. The majority of the system sits outdoors.
• Energy Efficiency: Because there is no loss of energy through ductwork (which accounts for up to 20% of the energy cost), these systems are exceedingly efficient. While your typical central HVAC systems may have SEER ratings of 13 or 14, a ductless mini-split offers SEER ratings of 20 or more (see our post What’s Your SEER?).
• Zoning: A mini-split is ideal for a room that is only used occasionally or is closed off part of the time: if no one is in the room, there is no reason to pay to heat or cool the space. It is also ideal for a room that will have vastly different heating or cooling requirements from the rest of your house, such as a sunroom or attic bonus room. A ductless mini-split can even be added to a room currently fed by your central HVAC system, but is hard to heat and cool compared with the rest of your house.
• Features: Many of the latest crop of mini-split systems offer a multi-speed compressor, wireless remote control, programmable timer, and many other innovations.
• Easy to Maintain: Most have washable, re-usable filters. Plus, it is much quieter than even the quietest window air-conditioner, and there are health benefits by not having ducts, which can gather dust, debris, and mold.

Counterfeit and illegally imported refrigerants pose real safety and health concerns to HVAC technicians and consumers, as we detailed in our earlier post (see Beware of Fake Refrigerants!).  In recent years, with the curtailment of the refrigerant R-22 and its subsequent rise in price, this problem has gotten worse.  Now, there is much more scrutiny by the various authorities such as the EPA, IRS, and customs officials.

The Industry Fights Back

The HVAC industry now has much greater focus on recordkeeping and knowing the source of all supplies. To fight against counterfeit labeling, one refrigerant manufacturer has added a patented security hologram that provides immediate visual verification that the refrigerant is a genuine DuPont product.  The Izon® label is a unique 3D security system and contains an embedded code that allows for greater product tracking and traceability (see more info here).  Some refrigerant suppliers have begun routinely testing the contents of refrigerant cylinders they receive, using a halide test or a portable refrigerant analyzer, to spot contaminants and counterfeit products before they wind up in a consumer’s system.

What You Can Do

Here are some things you do, to avoid becoming a victim of counterfeit refrigerants:

1. Price: If the pricing you are quoted seems too good to be true, it probably is. The going price per pound for R-22 is about $45-95, and for R-410a it is $30-70. Know what you’re getting and whether the price includes installation. Get quotes from multiple suppliers. If one seems crazy low, it could be it is an illegal import or counterfeit.

2. Selling to Consumers: Although you can find cylinders of refrigerant selling online for much cheaper, it is illegal for a retailer to sell directly to consumers or to anyone who does not possess EPA 608 certification. If they will sell directly to you without this certification or do not ask to verify your certification, that is a big red flag!

3. Know your Supplier/Contractor: How long has your supplier or contractor been around? What is their reputation? Can you get in contact with them when you need to? Seek online or first-hand reviews from their customers. Verify that your HVAC technician carries Section 608 certification from the EPA. If they can’t or won’t show you proof of certification, that is a big red flag.

4. Verify the Cylinder: Look closely at the labeling of the refrigerant your technician is using. Product names such as R-22a, 12a and 290 should not be used in a residential HVAC system. Verify that the technician is adding refrigerant from a cylinder that is clearly marked to be the “right” kind (if your system needs R-22 that it says R-22 on it) and has the manufacturer’s name on it.

5. Label Your Unit: Always insist your contractor/installer label your unit with the type of refrigerant they added. If they did use a legal R-22 substitute, such as R-422D, make sure it is labeled as such. That way, the next technician working on the system won’t put R-22 in your now 422D unit.

Important Tip
If you’re having to add refrigerant to your system, it means you have a leak (see our post Fix the Refrigerant Leak Now!). If you have an older HVAC system that uses R-22, consult a reputable HVAC technician to see if it makes sense to continue investing in your existing system or if you’d be better off replacing it with a system that uses the more environmentally friendly R-410A refrigerant. Unfortunately, R-22 charged units are not compatible with R-410A refrigerant, so you’ll have to replace the entire system (to help you weigh the pros and cons, see our post Repair or Replace?). On the bright side, if you do invest in a new unit, it will be more environmentally friendly and energy efficient, so you’ll save money on your monthly cooling costs, and those long-term savings can really add up!

Counterfeit and illegally imported refrigerants have existed in the HVAC industry for years. With R-22 increasing in price due to the government phase out (see previous post An Update on the Refrigerant R-22), people are doing anything they can to get their hands on cheaper solutions. Some refrigerants coming into the U.S. from other countries are not just imported illegally, but they are counterfeit, posing safety and health concerns to technicians and consumers. If you are having your air-conditioning system serviced, be alert to the various scams out there!

Unapproved Substitutes

Several companies have been penalized by the federal government for illegally marketing and selling other hydrocarbon products such as ES 22a as a replacement for R-22. (see  EPA vs EnviroSafe and EPA vs Northcutt).  According to the EPA,  use of ES 22a –  a refrigerant meant for window air conditioning units – creates the potential for explosion and fires, and is a serious risk to human health and the environment. R-22 air conditioners weren’t built to handle the level of pressure or flammability these substitutes pose. In particular, R-22a, which uses propane, creates a fire hazard. Approved alternatives to R-22 do exist, such as R-422D, so check with your HVAC contractor.

Unapproved Additives

Some vendors have blended the refrigerant with flammable substances such as propane and butane, or with a pine-scented odorant (see R-22a Safety). These have been sold under the names OZ-12®, HC-12a®, and DURACOOL, to name a few. Use of flammable refrigerants as a retrofit in equipment that was designed for non-flammable materials presents risks to consumers, equipment, and service technicians, and will void your equipment’s original manufacturer’s warranty. There are stories where the compressor burst into flames, the technician sustained serious burns, and the siding was melted off the house!

Counterfeit Refrigerants

Some counterfeit or contaminated refrigerants have counterfeit labels on the cylinders and packaging, so you can’t tell what’s actually inside. Contaminated refrigerants can cause a variety of issues, ranging from increased energy use and decreased cooling performance, to significantly reducing the operating life of your system, and causing injury and equipment failures.  Plus, many counterfeit  products contain ozone-depleting substances which are illegal. In China, 18 people were arrested from 4 criminal gangs, and 5 illegal production facilities were found, along with 11 storage warehouses and 2 sales offices. Over 28,000 canisters of fake R-134a and other refrigerants were confiscated along with 20 tons of raw materials (see report here).

Contaminated Refrigerants

Many refrigerants, including R-22, R-134a, R-404A, and R-410A, have been found to be badly contaminated (see report here). One of these contaminants is methyl chloride (also called R40 or chloromethane). It reacts with the aluminum and metal alloys used in the internal components of your HVAC system, causing corrosion and a volatile by-product that burns on contact with air. Exposure of the system’s contents to air and/or moisture could result in production of a strong acid and violent chemical reaction. This contaminant was responsible for a fatal apartment fire in 2014.

In our next post, we’ll tell you what the HVAC industry is doing to fight back and what you can do to avoid becoming a victim of fake refrigerants.

Cleaning the air conditioner coils is part of regular spring and summer HVAC maintenance and is something homeowners can do themselves. Dirty coils can adversely affect your air conditioner’s performance, and when the heat index creeps up past 100 as it has the past few days you need to get every bit of cooling you can from your air conditioning equipment! Any debris on the coils increases the static pressure across the coils and reduces your system’s efficiency. Clean coils can boost your cooling capacity by up to 30%!

Symptoms of Dirty Coils

The coils are the part of your system where the actual transfer of heat occurs. Anything that insulates them will not only impact efficiency, but also will increase operating cost, and increase the likelihood of equipment failure. If you find your compressor keeps getting louder with each passing month, or that the compressor is overheating and turning itself off (leaving just the fan still running), cleaning the coils is a great place to start to remedy the situation.

Start With the Basics

1. Check around your outdoor HVAC equipment and eliminate all obstructions within 3 feet all around the unit. That means trimming bushes, weeding, and removing all debris. Don’t allow the lawn mower to discharge grass clippings onto the unit, or allow mulch or leaves to bury the bottom few inches, because it will restrict airflow, which will decrease efficiency and damage the unit.
2. Check to see whether any of the fins have been damaged by mowing equipment, hail, or other calamity. Fins are the fine metallic blades that surround the condensing unit. If they have been bent, crushed or have rocks lodged in them, this will need to be remedied.
3. Check to make sure the foundation upon which the outdoor unit sits is level. This is typically a concrete pad, but could also be plastic or rubber. Often, due to settling, erosion or drainage issues, these can crack, sink or become unlevel.  This puts strain on coolant lines, and could bend or break copper or electrical lines, or cause water to puddle in the unit. Make sure the pad raises the unit out of the dirt and that there is adequate drainage around it, so that water does not pool near it during a hard rain.
4. Don’t forget that you must turn the unit off before cleaning it. This doesn’t mean simply that the unit is not running (e.g., set to a higher temperature), but rather the unit should be turned off at the switch usually a separate 240V power box near the unit – or at the circuit breaker box.

With these things addressed, you’re ready to start cleaning the coils.

Coil Cleaners

Many manufacturers make coil cleaning products to aid in dislodging the contaminants on the coils. Some coil cleaners come in foaming aerosol cans, others are liquids or powders that must be mixed with water and used in a pump sprayer, still others are solvent sprays. Generally, these coil cleaning products are highly acidic or alkaline, and are harmful when inhaled or when they touch skin, causing irritation and in some cases burns. If you plan to use any of these coil cleaning products, be sure you are not downwind of the spray and that you are wearing gloves and eye protection. And here’s a tip: if you’re using them in a pump sprayer, this stuff can eat out the seals, so you’ll need to use a special heavy-duty chemical-rated sprayer.

> > > Note: All types of coil cleaners are strong chemicals and must be handled with care. The manufacturer’s directions should be read carefully and followed precisely to provide the best results.< < <

What About Detergents?

Many coil cleaners are referred to as “detergents,” but do not confuse this with dishwashing detergents or laundry detergents! Never use those types of detergents on your HVAC equipment, as most have chemicals in them that are corrosive to metals. The aluminum, copper and metal alloys used in the manufacturing of fins and tubing, as well as the unit’s plastic blower wheel and diaphragm (in the case of mini-split systems), are more sensitive and must be cleaned with a safe, non-acid cleaner.

Technique Matters!

Whether you’re using a coil cleaner or not, you’ll need a water source.  Never use a pressure washer!  Doing so could damage the coil fins and disperse chemicals into unwanted areas. Instead, use a standard garden hose. Begin by spraying the water from the inside of the unit outward, rather than from the outside inward, to prevent pushing debris further into the unit. Once you are certain all the debris has been dislodged, you can do final rinsing in all directions. In cases where there might be a thick film of dust, pollen, and grass clippings around the unit, a shop-vac can be used to remove such debris before washing the coils.

Our Recommendation

We recommend coil cleaner chemicals only if you have several layers of oily grime and only if they are used by a professional. Here’s why: These cleaners, especially the foaming kind, can spread into hard-to-reach areas. If they are not completely rinsed out, they can corrode the metal and damage the unit. Coil cleaners are tough chemicals that can not only burn holes in your clothes (which is why you must wear protective equipment), but can damage paint. Consistent use of these cleaners over time can dissolve the outer metal and diminish the life of the coil, so we do not recommend them for routine maintenance. We recommend using just a garden hose and water.

Results

After cleaning the external unit, and turning the A/C back on, you may notice that it is many times quieter than it was before. That’s because the motor can work less and cool more efficiently. Few routine chores will pay off more handsomely, both in comfort and in dollars saved, than a simple coil cleaning. You’ll also prolong the life of your air conditioner and have quieter operation. So what are waiting for?

Perhaps you’ve read or listened to one of our earlier posts entitled “Fix the Refrigerant Leak Now!” so you know how expensive refrigerant leaks can be! With the phasing out of R-22, a “shot of Freon” (as it is often called), could run you $400 or more. And there’s no telling whether that will last a couple of months or a couple of weeks! Plus, it is detrimental to the environment, causing a depletion of ozone in our upper atmosphere. If you recharge the system several times, the oil in the compressor will deplete enough to damage the compressor, and then you may require a major and expensive repair! A properly-working air conditioner does not consume or use up refrigerant, so if it is running low on refrigerant, there is a leak somewhere in the system. But where? In this post, we’ll talk about the most likely culprits.

Schrader Valve

The Schrader valve, also called the core valve, or service valve, is the port you hook up to when servicing the system. That’s why finding a leak here can be so elusive: while it is in use, it doesn’t leak. It’s only when it is not engaged that the leak can be detected. Often, this can be as simple as putting a soapy solution around it and watch for bubbles to form, or using an electronic leak detector. The Schrader valve can become leaky when debris gets stuck in it, or when the rubber o-ring deteriorates. It used to be that to swap out the valve with a new one required removing all the existing refrigerant in the system (pumping it down) first. But now there are some specialized tools that allow you to swap out this valve while the system is still under pressure. After swapping it out, the system can be topped off with refrigerant. Consider yourself lucky if this is the problem because it is easily repaired.

Condenser Coil, Evaporator Coil, or Accumulator

The evaporator coil picks up heat from indoor air, and the condenser coil releases heat into outdoor air, so these coils are essential for heat exchange. Either or both can develop leaks over time. In some cases, you may be able to hear the hissing sound emanating from the coil and can determine where the leak is. What’s more likely is that the coil has developed microscopic “pin holes” in several places. That’s because these coils are typically made out of copper, which is particularly susceptible to pollutants such as formaldehyde which is often found in our homes in flooring, furniture, hairspray, and cleaners. Formaldehyde turns into formic acid which causes corrosion on the inside of the tubing. Ironically, newer systems that meet the government’s mandate for increased efficiency may be more susceptible to these kinds of leaks. That’s because A/C manufacturers found they can raise the efficiency of their equipment by using thinner copper in their evaporator coils, thus allowing faster heat transfer. Some A/C manufacturers have switched to aluminum coils to lessen the probability of this type of corrosion. Heat pumps typically have accumulators made of steel, which will rust over time.  Any of these types of causes are very expensive to address because they require replacement of the coil or accumulator which is a very expensive part, plus it requires a complete depressurizing of the system (withdrawing all refrigerant or “pumping down”).

Joints, Seals, Lines and Tubing

Vibration of running the system, as well as environmental pollutants, can cause joints, rubber seals and copper tubing to weaken, split, separate, or rust. A lawn mower or nail may have punctured a line. Steel parts will rust if not galvanized or made rust-proof. Age is also a factor, because the system is under high pressure causing the walls of the tubing to thin and weaken over time. These leaks can be hard to find and may require disassembly of the unit. To locate the source of the leak may involve injecting a tracer (a fluorescent dye) into the system and then re-checking the system about 10 days later using a UV lamp to see where the dye has leaked out. Once the source is found, the joint, connection, or hole in the tube can be fixed by re-soldering, cutting it out, replacing it or by-passing it. The diagnosis and repair of these conditions can be time-consuming and thus expensive.

A Dilemma

Depending on the age of the air conditioner or heat pump, and the type of refrigerant it uses, you may be faced with a dilemma: You may need to consider replacing it rather than repairing it. Weighing the costs can be tricky, so you’ll want to read our post entitled “Repair vs Replacement.” Keep in mind it is possible to repair one refrigerant leak and have another one develop in a different location shortly thereafter. Whatever you decide, doing nothing is not an option. Sure, the cost to repair or replace your system may be higher than simply adding another “shot of Freon,” but not repairing a leak causes recurring expenses that will only escalate, risks major damage to your system that could be even more costly, and injures the environment.

DIY? Not!

Finding the source of a refrigerant leak requires the use of specialized tools and supplies, specialized training, and is something few homeowners can do themselves.  Recharging the system with refrigerant whether the “old” R-22 or R-410A equivalent, or the new refrigerant R-422 is definitely not something a homeowner can do since it requires a government license to order and use these refrigerants. Depend on the experts at Interstate AC Service to diagnose the source of your leak, fix it, recharge your system, and get your air conditioner operating at peak efficiency.