UNDERSTANDING THE DEFROST CYCLE OF YOUR HEAT PUMP

Understanding Defrost Cycle

During winter months many heat pumps will need to go through a “defrost” cycle during operation. Often this has not been explained well before installation, which leads to a lot of confusion about why the heat pump is not working. This document is provided to help users understand the defrosting cycle and address any concerns.

What is a “defrost cycle”?
In heating mode a heat pump extracts heat from the outside air and transfers it inside your premises to warm it. When the ambient temperature outside gets very cold (close to 0°C or below) the moisture in the air freezes on the outdoor unit’s heat exchanger as the fan blows the air across it. A defrost cycle is simply the system recognising that ice has formed or begun to form and automatically fixing this.

Why does my unit have to do a defrost cycle?
Any ice building up on the outside heat exchanger reduces the airflow across it, which will effect the efficiency, sometimes reducing it dramatically. In extreme cases this can also cause damage to the outdoor unit.

How do I tell if my unit is in a defrost cycle?
Inside you will notice the unit will stop heating, the indoor fan will stop and depending on the model there will usually be some form of visual indication like a light on the unit (usually the “run” light) will blink continuously. Outside, the outdoor fan will also have stopped and the compressor will be running.


How often will my unit go in to defrost mode?
There are a number of factors that influence how often a unit will go in to defrost mode. Some of these include:
The outdoor temperature and humidity
The amount of heating load the unit is trying to deliver
The condition of the heat pump system.
There are timers built in to the computer control of the unit that restrict how often defrosting can occur. Generally a unit must run for a minimum of around 35 minutes after starting up before completing its first defrost. From there defrosts should occur no more frequently than approximately every 35 minutes.

Once my unit is defrosting how long will it take?
Either of two factors can bring the unit out of a defrost cycle. Firstly, if the sensors on the outdoor unit detect that it’s heat exchanger temperature has risen enough, the unit will stop defrosting. Secondly, if the sensors do not stop it beforehand, the maximum time a unit will be in defrost cycle is around 10 minutes.

It is important not to stop the unit before the defrost cycle has ended, because if the unit is restarted shortly afterwards it will run very inefficiently and may cause damage to itself.


My unit is defrosting frequently / not delivering enough heat – what could be wrong?
Regular defrosting, or a lack of heat could be caused by a number of factors.

If the unit has operated like this since it was first installed (first cold snap), you may be operating it incorrectly or it may be undersized for the space it is trying to heat. Initially you should consult your instruction manual to ensure you are operating the unit correctly. If this doesn’t remedy the problem you should consult your installer or another reputable heat pump installer. They can assist you to ensure correct operation, and correct sizing.

If the unit is undersized for the space it is not faulty. The responsibility for correctly sizing the unit initially rests with the installing company – they will need to remedy the situation if the unit is too small.

A recently developed problem may be an indication of a fault or maintenance required. You can perform some basic maintenance yourself by cleaning the filters on your indoor unit, and ensuring that your outdoor unit is clear of foliage and the heat exchanger is not blocked. If this doesn’t remedy the problem you should consult your installer or another reputable heat pump installer.


Is there any way I can help to reduce defrosting?
Yes there certainly is. Keep your unit well maintained (as above) and ensure you are operating it correctly. This will help a lot.

Of course the less load you place on the unit the less frequently it will need to defrost in cold conditions. Ultimately permanent fixes such as installing insulation in ceilings, walls and under floors will help reduce your heating requirement (and ultimately save you money). More immediately, keeping doors closed and curtains drawn will also help to reduce your heating required.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about Indoor Air Quality and other HVAC topics, click here to visit our website.

Lyric™ Wi-Fi Thermostat

What will the think of next?

The Lyric™ Wi-Fi thermostat delivers comfort at home and savings when you’re away, automatically, based on your smartphone’s location using geofencing technology. According to the company, the device features no complex menus, complicated programming, or a need to set schedules. The Fine Tune feature factors indoor and outdoor temperature, humidity, and weather into its algorithm, enabling it to provide the most comfortable temperature for homeowners. Beyond a smartphone, the temperature can be managed using the company’s familiar round dial control on the thermostat itself. When a user approaches the unit, a built-in proximity sensor signals the display to turn on and show current temperature and the home’s heating or cooling status. A soft halo of light in orange (heating), blue (cooling), or green (away/energy savings) momentarily illuminates the thermostat to indicate it is making temperature adjustments. The unit will be available for retail in August 2014.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about Indoor Air Quality and other HVAC topics, click here to visit our website.

Trilogy 45™ Q-Mode™ Variable Speed Geothermal Heat Pump

The Trilogy 45™ Q-Mode™ variable-speed geothermal heat pump system features efficiencies of 45 EER and offers convenient programming, monitoring, and control for homeowners and dealers over the Internet from any Wi-Fi-enabled device, according to the company. The unit’s patent pending Q-Mode technology reduces hot water operating costs by providing full-time, year-round domestic hot water heating at over 500 percent (5.0 COP) efficiency. According to the company, the Q-Mode technology also provides no-cost cooling by automatically drawing heat from a space into the unit’s iGate Smart Tank™ hot water storage tank. The tank’s polyethylene exterior further protects it from corrosion. Featuring iGate Connect™ technology, the Trilogy 45 Q-Mode residential geothermal heat pump system provides dealers with complete diagnostics and operating data via any Wi-Fi enabled device over the Internet.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about Indoor Air Quality and other HVAC topics, click here to visit our website.

SecurityWebb™ A/C Security Solutions, LLC

No product available on the market can guarantee that a thief or vandal will not strip your HVAC unit of its copper. This product takes a multi-faceted approach to theft deterrence. The color is RED and when a thief sees the SecurityWebb™ on your HVAC unit, they are likely to move to an easier mark. This product utilizes unique high strength security hardware and cable that is nearly impossible to cut with a sawsall or remove from the unit. Tamper switches are provided to wire into a security system in case an attempt is made to damage your HVAC equipment.

This product is manufactured for installation in coastal locations utilizing hot-dipped galvanized, stainless steel and powder coated aluminum components.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about Indoor Air Quality and other HVAC topics, click here to visit our website.

LIGHTNING STRIKES

Summer is upon us and it is time for the lightning strikes to increase. Have you thought about a surge protector for your home and your air conditioning system? Lightning and power surges can be very damaging and costly to a homeowner. Protect your investments. Call us for a quote on protecting your air conditioning system.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about Indoor Air Quality and other HVAC topics, click here to visit our website.

Berner Intl. Corp.: Single-Length Air Curtains

Some interesting information. The air curtains are usually used in restaurants, retail stores, and commercial business.

Single-length 7-, 8-, 9-, and 10-foot-long models have been added to the ANSI/NSF 37-certified E-Zone and K-Zone (EZN and KZN Series) air curtains. The EZN and KZN Series are now available in nine widths ranging from 3-10 feet in length. Each new length model uses the same E-Zone/K-Zone 8-½-by-8-inch cabinet design. The air curtains are suitable for walk-in coolers, pass-thru windows, concession windows, patio openings, service/customer entry doors, and other doorways that need environmental control in the food service, dock-and-door, and HVACR markets. Available in custom colors and durable power-coat finishes. Multiple air directional vanes constructed of strong heavy-gauge aluminum assure proper deflection and airflow to the outdoor threshold, said the company. Universal mounting system offers flexible horizontal or vertical mounting options.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about Indoor Air Quality and other HVAC topics, click here to visit our website.

UNLICENSED HVAC CONTRACTORS

Report from the Air Conditioning│Heating│Refrigeration News on unlicensed HVAC contractors which seems never to stop in all contractor fields, not just HVAC. This was published June 16, 2014:

While hiring an unlicensed HVAC contractor may present itself as a money-saving deal upfront, many homeowners experience a bevy of bad fortune through crooked craftsmanship, untrustworthy diagnosis, unreliable repairs, and more. These actions, and a number of other concerns, may quickly convert preconceived cash savings into an invaluable hassle.

“Individuals who work outside the laws and regulations are a scourge to this industry,” said Charlie McCrudden, senior vice president, government relations, ACCA. “They take advantage of lax enforcement of permitting rules, licensing requirements, and the Clean Air Act. Unfortunately, we’ll never know how pervasive the problem is, since it’s so difficult to keep track of how many individuals are posing as professional HVAC technicians.”

Contractor Impact
In a trade where reputation is everything, reputable contractors and associations are continuing to stress the importance of contractor licensing to homeowners and those operating without the proper licensing.

Rocco DiBenedetto, owner, All Air of South Dade, Homestead, Florida, is on the forefront of the issue. Since 2009, Miami-Dade County has ceased enforcement of code requirements for contractors. In response, DiBenedetto formed the Miami-Dade Contractors Alliance, which works to regain enforcement in a region where unlicensed workers are running amok.

“It’s destroyed our ability to be honest contractors,” DiBenedetto said. “We’re still honest and ethical, but we go to houses and they tell us we’re price gougers. We’re not, but nobody else charges the real price.”

DiBenedetto said it’s frequent to hear advertisements offering air conditioning systems for $1,800. “In Broward County, 20 minutes north of us, they have an active task force and issue hundreds of citations a month for unlicensed activity,” DiBenedetto said.

Although not every state requires a license, it’s critical for the overall credibility of contractors to gain one in states where licensing is required.

“The issue of state licensing re-quires someone to show capability, to show experience,” said Paul Wadsworth, president, P.K. Wadsworth Heating and Cooling, Solon, Ohio. “To have a state license is important. It shows the individual has studied his craft and knows something. It’s not just some guy who decided he was going to slap a magnet on the side of a pickup truck and all of a sudden he’s a contractor.”

Steve Lauten, president, Total Air and Heat Co., Plano, Texas, said when he took the state licensing exam many years ago, he felt the questions were valid. “Now they’re being told to write questions so the person with the worst skill set can answer them. It seems they’re trying to make the playing field the same for everybody,” he said.

Lauten pointed out that licensing, though, isn’t the end-all, be-all to being considered an ethical, quality contractor. “I think consumers are getting smarter, but the thing I’d mention is that just because your guy has a license, it doesn’t mean he’s going to do the job the way it should be done,” he said. “In Texas, we’re required to pull permits any time we’re within an incorporated city. And I would say on 90 percent of the jobs we bid, our state’s licensed competitors aren’t pulling permits.”

Evolution is a Mystery
As the HVAC industry continues to evolve beyond heating and air and into things such as IAQ and home-performance improvements, the role of a licensed, knowledgeable contractor is becoming even more important, said Wade Mayfield, president, Thermal Services Inc., Omaha, Nebraska, and chairman of the board of North American Technician Excellence (NATE).

“Technicians don’t just deal with heating and or cooling, they manage people’s livelihoods,” Mayfield said. “Properly licensed and trained technicians not only service and clean the units, they mitigate health hazards that exist in the home from IAQ problems, such as mold, toxins, carbon monoxide, etc. We also must realize that heating and air systems account for 30-40 percent of a home’s energy usage, so properly trained technicians have the skill set necessary to properly install and service the units in a way that optimizes energy efficiency.”

As the industry works to get its message across to consumers, some are taking notice, McCrudden said.

“Consumers are savvier about contractors, thanks to online review sites and media ‘sting’ operations that single out the bad actors,” McCrudden said. “As a result, their expectations are higher. And homeowners no longer call a contractor just when there’s a problem. The energy-saving improvement programs that incentivize an energy audit or pay rebates for upgrades have more homeowners thinking about ways to increase their system performance while saving money.”

In areas such as where DiBenedetto operates, though, it’s becoming tougher and tougher for the consumer to figure out who is licensed and insured as each day goes by without enforcement.

“If you decided you wanted to eat organic apples and you see there’s one that’s $5 and another that’s $2, how the hell do you distinguish between what’s organic and what’s not?” asked DiBenedetto. “There are tons of trucks running around with fake numbers on them. Those might as well be lottery numbers. The police don’t even know what’s real and what’s not. That’s how bad it is.”

Mayfield noted the issue of enforcement can often be a Catch-22 for contractors, as the only path to combat unlicensed contractors is through regulation, he said.

“It’s really a double-edged sword for contractors,” Mayfield said. “Contractors resist regulation, but need regulation matched with enforcement to offset unlicensed contractors. Done correctly, regulation in this context will protect the health and wellbeing of the public and allow licensed contractors to serve their customers at a high level.”

Importance of Licensing
As the industry continues to evolve, the credibility of hiring a licensed contractor is of the utmost importance, Wadsworth said, noting consumers really have a lot of due diligence to do these days.

“When I entered this trade 40 years ago, it was a much simpler business,” Wadsworth said. “The equipment was much simpler, much more straightforward. But, today, you have to know building science, sophisticated controls techniques, and so much more. That comes with requirements. You have to know how to correctly apply the latest technologies.”

DiBenedetto said his integrity and desire to adequately serve the customer will keep him from following in the footsteps of his Miami-Dade peers. “I’m not going to ask a guy to come in and do a great job for a customer and then tell him I’m going to 1099 him and ask him to work under shady conditions,” he said.

McCrudden referred to those working without a license in areas when licensing is required as bottom feeders, stating they drag down the image of upstanding contractors who follow industry-recognized standards.

Lauten said adequate licensing and following proper protocol is a key component to retaining the industry’s credibility with consumers.

“You’ll hear a lot of people say licensing doesn’t mean anything. I disagree. If plumbers and electricians have to be licensed, then air conditioning contractors should be licensed, too. There should be something that holds contractors accountable to doing jobs the way they should be done.”

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about Indoor Air Quality and other HVAC topics, click here to visit our website.