Category Archives: Power vent water heaters

Troubleshooting Power Vent Water Heaters

Venting

When troubleshooting a Power Vent water heater the venting often goes unnoticed even if there is an issue. The venting is so important to inspect on Power Vent Water Heaters because if they are sloped the wrong direction condensation will makes its way to the blower and damage it. Power vents don’t always form condensation, but there are a couple different variables that do cause them to condensate.

-Ambient temperature and humidity of installation location

-Ambient temperature and humidity of venting space

-Vent distance, slope, and correct product usage

-Vent has slope minimum of 1/8″ AWAY from the blower – Horizontal Applications

-Know the proper vent lengths for the model water heater (see table below)

These are the variables you need to pay especially close attention to when inspecting the venting. If you do notice an issue where the Power Vent is condensating a condensate kit is available to install. This is a Fernco exhaust adapter with a drain outlet that you pipe to the drain using vinyl tubing. An inexpensive part that will solve the condensate problem.

Check for vent blockage and determine if the vent could become clogged by surrounding vegetation. If so, consult with the home owner on a solution to make sure the problem does not repeat itself.

Its extremely important to make sure there is adequate air for combustion and ventilation. An insufficient supply of air will cause re-circulation of combustion products resulting in air contamination that may be hazardous to life. In Such conditions you will notice a yellow,luminous burner flame, causing carbon build up or sooting of the combustion chamber, burners and flue tubes with possible damage to the water heater.

Vents are susceptible to freezing and can be very easy to overlook. If the burner wont stay lit you should check to make sure there are no obstructions and investigate the possibility of frozen vent.

Troubleshooting codes and Vent Length Table

The link below includes a table to troubleshoot any issues you may have

The link also includes Maximum vent length including number of allowed elbows

vent-length-table-troubleshooting-codes-and-cause

Proper Combustion Air

Combustion air is very important for a water heater to run correctly. All different variables should be considered. When an exhaust fan is installed in the same room with a water heater, sufficient openings for air must be provided in the walls. Undersized openings will cause air to be drawn into the room through the venting and causing circulation of combustion products. A very common solution to this problem is the installation of a louvered door.

The formula to correctly determine proper openings

All air coming from inside the building: an opening must have a minimum free area of 1 inch² (6.5 cm²) per 1000 BTU (0.29 kw) per hour of the total input rating of all gas utilization equipment in the confined space, but not less than 100 inches² (645 cm²). One opening must be within 12 inches (31 cm) of the top and one with 12 inches (31 cm) of the bottom of the enclosure.

All Air coming from Outdoors: The confined space must be provided with two permanent openings, one commencing within 12 inches (31 cm) of the top and one commencing within 12 inches (31 cm) from the bottom of the enclosure. The openings must communicate directly, or by ducts, with the outdoors or spaces (crawl or attic) that freely communicate with the outdoors.

  1. When directly communicating with the outdoors, each opening must have a minimum free area of 1 inch² (6.5 cm²) per 4000 BTU (1.2 kw) per hour of total input rating of all equipment in the enclosure.
  2. When communicating with the outdoors through vertical ducts, each opening must have a minimum free area of 1 inch² (6.5 cm²) per 4000 BTU (1.2 kw) per hour of total input rating of all equipment in the enclosure.
  3. When communicating with the outdoors through the horizontal ducts , each opening must have a minimum free area of 1 inch² (6.5 cm²)  per 2000 BTU (0.6 kw) per hour of total input rating of all equipment in the enclosure.
  4. When ducts are used, they must be of the same cross-sectional area as the free area of the openings to which the connect. The minimum dimensions of rectangular air ducts must be not less than 3 inches (7.5cm)

Specially Engineered Installations

The requirements noted under the CONFINED SPACES above must not necessarily govern when special engineering, approved by the authority having jurisdiction, provides an adequate supply of air for combustion, ventilation, and dilution of flue gases.

Sequence of Operation

The sequence of operation is important to know so you can properly diagnose the problem.

Control Sequence of Operation

Start up sequence

Upon powering up, the control checks for the presence of the resistive plug, if the resistance is in the expected range the control will begin normal operation after 5 to 8 seconds.

Normal Heating Sequence

  1. The thermostat senses a need for heat.
  2. The control checks the pressure switch condition.
  3. If the pressure switch is open, the control sends power to the blower motor.
  4. The blower starts moving combustion air through the combustion system.
  5. The pressure switches closes.
  6. The control senses the closed pressure switch and starts the ignition process by providing a spark at the pilot electrode and allowing gas to flow to the pilot.
  7. When the pilot is lit the gas control senses the pilot flame and opens the main gas valve.
  8. The main burner is lit.
  9. The main burner and blower continue to operate until the thermostat is satisfied.
  10. When the thermostat is satisfied the main and pilot gas valves close.
  11. The blower operates for a short post purge period before shutting down.
  12. The water heater remains in the stand-by mode until the next call for heat.
  13. Make sure Power Vent is plugged into a grounded outlet.
  14. Make sure you have correct continuinty

Maintenance

  1. Annually check the operation of the thermostat
  2. The flow of combustion and ventilation air MUST NOT be restricted. Clear the combustion air openings of any dirt, dust, or other restrictions. WARNING! The ventilation air system may be HOT.
  3. At all times keep the water heater area clear and free from combustible materials, gasoline and other flammable vapors and liquids.
  4. Bi-annually conduct a visual check of the main and pilot burner flames to determine that they are burning properly. see Burner Flame Check. If sooting or other burner anomalies are evident, shut down the water heater by turning off the gas per the instructions listed in this manual or as listed on the water heater.
  5. Annually remove the inner door and main burner assembly to clean orifices and related parts of any dirt or other foreign material. Inspect the burner ports for obstructions or debris and clean with a wire brush as needed. Wire brush and/or vacuum clean the combustion chamber as needed to remove scale deposits and debris. NOTE: It is imperative for proper operation of the water that the inner door replaced in the original location.
  6. At least once a year, check the combination temperature and pressure relief valve to insure that the valve has not become encrusted with lime. Lift the lever at the top of the valve several times until the valve seats properly without leaking.
  7. Monthly drain off a gallon of water to remove silt and sediment.
  8. If the combination temperature and pressure relief valve on the appliance discharges periodically, this may be due to thermal expansion in a closed water supply system. Contact the Ace Hi Plumbing, Heating and Air to help correct this problem. Do not plug the combination temperature and pressure relief valve outlet.
  9. A combination sacrificial anode rod/hot water outlet nipple has been installed to extend tank life. The anode rod should be inspected annual and replaced when necessary to prolong tank life. Water conditions in your area will influence the time interval for inspection and replacement of the anode rod. The use of a water softener may increase the speed of anode consumption. More frequent inspection of the anode is needed when using softened (or phosphate treated) water.
  10. The blower has sealed motor bearings and does not require adding oil.
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Tank Water Heaters – Bradford White

There are many different choices out there on the type of tank water heater to have installed in your home. And we will explain to you why we choose Bradford White over many of the other brands.

When your spouse doesn’t have hot water do you want to wait over the weekend while waiting for parts to come in for your other brand water heaters? Bradford whites parts are readily available for same day repair. There should be no reason you go that weekend or even a night without hot water when you chose to install a Bradford White product.

While many other companies have moved manufacturing facilities out of the country, Bradford White stays invested in American Jobs and Growth. As demand grows they continue to grow their manufacturing facility in Middleville, Michigan.

Types of Water Heaters

There are many different types of water heaters to choose from. If you already have a specific type installed it is recommended you go with the same type.

Direct Vent

Direct Vent water heaters utilize a co-axial (pipe inside a pipe) vent pipe that takes air in from the outside (outer vent) and vents combustion gases directly back to the outside (outer vent). It is perfect choice for situation with insufficient combustion air. Direct vent water heaters water is heated by the heat of fuel combustion. A Direct vent system typically results in lower heating costs, because the exhaust gases are vented vertically, with no extra power required as in the case with the power vent water heater. No electricity required. Used in both LP and Natural Gas applications.

direct vent

Atmospheric Vent

This is the most common gas water heater. Its called “atmospheric vent” because warm air rises, the hot gases created by combustion are pulled by natural convection up a vertical metal flue through the roof to the outside. The air around the base of the water heater is pulled into the burner chamber for combustion by the same convection flow. Its a very simple system that does not require electric power or moving parts. Which is why you see these used in most applications.

There is also a Damper Atmospheric Vent model that feature an automatic flue damper that helps reduce stand by heat loss. The flue damper, combined with additional insulation and heat traps, These units have one of the highest Energy Factor (EF) ratings for atmospheric vent models.

atmospheric vent

Power Vent

Power Vent models are power vented for positive exhaust. They offer greater installation flexibility with the ability to vent through the wall or roof, with either 2″ or 3″ PVC, ABS or CPVC pipe. Power vent water heaters use a blower or fan to exhaust gases by pushing them through the vent pipes that are horizontal. In some situations, this may be the only type of water heater that makes sense, because a chimney or vertical vent is not necessary. Some locations don’t have access to a chimney or vertical vent so your options are limited. These are nice because a Power Vent can be vented by simply running inexpensive pipe horizontally.

However the drawback to this type of water heater is the total cost considering the blower/fan portion of the vent requires electricity to operate as well as the cost of the blower and running a power line to the unit. Noise is also a disadvantage from the blower fan running. But when installed properly the noise can be minimized or nearly eliminated.

power vent

Power Direct Vent

Power Direct Vent models are the solution to installation that lack sufficient air for combustion and require installation flexibility. All models of power direct vent water heaters can vent vertically or horizontally and are also approved for direct-vent, closed combustion applications. Solid core PVC is used for the exhaust vent and Cellular core PVC is used for the combustion air in. This application does require electricity to power the direct vent.

High Efficiency

 High Efficiency (HE) water heaters  extract heat out of the exhaust gases to heat the water, just like your standard Atmospheric Vent water heaters. But they include a secondary heat exchanger that maximizes the heat transfer process to extract as much heat energy as possibly out of the combustion process.

Sealed Combustion water heaters maintain the “seal” by using designated intake and exhaust pipes to connect them directly to the outside. They are controlled so when hot water is needed the blower kicks in and draws air directly from the outside into the combustion chamber, with the fuel, and the exhaust gets power vented directly out of the building with the same blower that drew it in but through another designated pipe rather then through a chimney.

Condensing is the next key process to achieve higher efficiency. A second heat transfer process is achieved by lengthening the exit path the exhaust travels using a secondary heat exchanger, frequently featuring a coiled design for maximum surface area, though some models use a reversed travel path (down, up, down again) And as this heat transfer occurs, the exhaust gases cool to the temperature where water vapor condenses out of the exhaust’s air stream back into liquid water (just like water from the air condenses on the outside of a cold drink), releasing the latent heat of vaporization which is used to further heat the water in the system. (The resulting liquid condensate leaves the system via a designated condensate drain.) The exhaust gases end up cool enough that PVC can be used for the venting, but those gases also lose stamina as they travel, which is why all HE units are power vented (fan assisted).

high efficiency water heater.png

Warranty

When dealing with warranty issues you commonly have to deal with customer service. Normally that would be a headache. But with Bradford White you know you are getting better quality customer service than any other manufacturer and will make sure you are happy with your product.

Warranties are among some of the biggest concern to the customer, with good reason. Which is why we stand behind Bradford White. When your tank fails and is under warranty there is a process that we must go through to get your tank paid for. We must pay for the new tank being installed and wait for reimbursement from the manufacturer. If we did not  originally install the product there is a chance that you may have to pay for the water heater and get reimbursed from manufacturer. Bradford White water heaters have fewer problems than any other brands. And when there is an issue they will go out of their way to make it right for the installer and the consumer.

Big Box Stores

Typically when choosing a water heater a customer will go to a Big Box Store and pick one out themselves. Normally this wouldn’t be an issue, but with water heaters you are not getting the quality of product that we can get from our distributor and often times you are spending more money for that water heater. This is being said from years of installing both products and seeing parts fail more frequently on models from big box stores. The parts for these water heaters are not as readily available for a quick and smooth repair. In many cases when going with a Big Box Store for your water heater install you will be dealing with their warranty department which can typically be a 7 day wait. With Bradford White water heaters, you know you are getting a quality product at a reasonable price. If any parts do fail on your Bradford White at any point it will be possible to have a same day repair. Compared to having to wait 2-5 days for parts to come in on your other models. With our customers best interest in mind we strongly suggest to stray away from Big Box Stores brands.

Energy Star

There are a few things to have in mind when considering installing an energy star water heater. They advertise a rebate associated with having a certain EF Rating of .67 (Energy Factor Rating). This rebate comes to around  $70 in Larimer County and may be even less depending on your County. Getting a water heater with this EF rating will cost you more money upon install. Usually 300-500 dollars more.You will on average save 7% annually. When considering this install you should also consider future repairs and how long you may have to wait for these parts. This should be a huge deciding factor because often times you may have to wait 2-5 days for your parts to come in and will have to suffer without hot water.

Overall we feel Bradford White is a better install option for our customers.

atmospheric vent diagram