Tag Archives: Water Heaters


The Eternal® tankless water heater is so sleek and elegant that you could install it in your living room. It is also resilient and durable enough to install outside of your home but requires an outdoor kit. The small size of this water heater is half of a standard 50-gallon conventional tank water heater but with up to 300% more output capacity. In addition to the small size, Eternal uses between 35% to 50% less energy than a standard 50-gallon gas-fired tank. Eternal also leaves one of the smallest carbon footprints in the industry. At just 3ppm NOx, it’s the only gas-fired water heater that has almost zero emissions.


Eternal’s patented heat exchanger features an infrared burner that pushes heat down and then back up 44 baffled pipes. This process uses the heat twice as opposed to standard burners that exhaust wasted heat straight through the top. Water surrounds the pipes to eliminate scale buildup that can occur inside piping. The large heat transfer area allows full flow through without reducing water pressure.

  • Stainless Steel exterior
  • Stainless Steel Heat Exchanger with built in 2 gallon reserve tank
  • Full flow design and dual activation (thermostat and flow) are compatible with water sense fixtures
  • Flexible NG / LP / Indoor / Outdoor / Direct Vent / Power Vent conversions in one unit
  • 3″ PVC venting up to 100ft
  • Clip-on components easily serviced by technicians
  • Patented self-cleaning utilizes turbulent flow to flush sediments out
  • Digital display screen for adjusting temperature and easy diagnostics
  • Endless hot water without water pressure drop
  • Up to 98% Efficiency saves cost, .096EF exceeds Energy Star, and qualifies for available government and/or local utility rebates
  • Ultra low emissions leaves almost no carbon footprint
  • Easy integration with recirculation and no startup lag eliminates cold water sandwich
  • Industry’s BEST 15-Year Residential / 5-Year Commercial heat exchanger no leak warranty

In a time where finding honest and well trained experts in the water heating industry is difficult, at Ace Hi Plumbing, Heating & Air, we pride ourselves in being a company you can trust. We provide excellent service, quick response and affordable prices. With such a large selection of water heaters today, choosing the right one can be time consuming. We know how valuable time can be and will make every effort to demonstrate that we are the best option for your plumbing and hot water needs. We service the Northern Colorado area including Loveland, Fort Collins, Windsor, Greeley, Evans, Johnstown, Longmont, Berthoud, Drake and Estes Park.



What is an Expansion Tank?

A water heater expansion tank is designed to help prevent fluctuations in water pressure and extend the life of a water heater. Fluctuations in water pressure can damage a water heater and water lines in the home’s plumbing system. The water heater expansion tank serves as an overflow receptacle by absorbing excess water volume that the water heater creates when heating water. Expansion tanks are normally installed above the water heater on the cold side before the water enters the water heater.

expansion tank

Thermal Expansion 

Since water expands when it is heated due to thermal expansion, the water heater creates extra water volume every time it heats water. The extra water volume creates excess pressure in the plumbing system and can cause damage to the water heater, fixtures and water piping over time. Extra hot water from the thermal expansion can be stored in the expansion tank and when hot water is demanded, it is put back into the water heater. Having an expansion tank also helps prevent dripping faucets and running toilets by keeping the extra built up pressure from reaching the fixtures and prematurely damaging them.

Water System

Homes commonly have a closed system which is a water system with a one way valve such as a check valve, a backflow valve or pressure reducing valve. In a closed system, this extra water pressure from thermal expansion can cause the most damage because the extra water pressure has nowhere to go since it cannot push back into the city water. Most cities require that expansion tanks be installed in closed systems. If you have some form of backflow preventer installed on the main water line you may be required to also have a water heater expansion tank installed. You can check local building codes or call the City Planning & Building Department in your area to find out more.

If you do not have a one way valve installed on the main water line, and therefore do not have a closed water system, you may still benefit from a water heater expansion tank.


If you are hiring a plumber to have a water heater installed it is a good idea to get a price for the installation of an expansion tank also. It may not be much more than you are already paying if it is done at the same time. Consider having an expansion tank even if it is not required since the benefits far outweigh the work and cost involved. For more information or to schedule an installation call ACE HI PLUMBING, HEATING & AIR at 970-667-0300 today. We have trained and experienced technicians who you can trust.

Types of Water Heaters

Types of Water Heaters 

Before purchasing a water heater it is always a good idea to know the different types and what will work best in your home.

  • Conventional storage water heaters offer a ready reservoir of hot water
  • Tankless or demand-type water heaters heat water directly without the use of the storage tank.
  • Heat pump water heaters move heat from one place to another instead of generating heat directly for providing hot water
  • Solar water heaters use the sun’s heat to provide hot water
  • Tankless coil and indirect water heaters  use a home’s space heating system to heat water
Conventional Storage Water Heaters 

Conventional storage water heaters are the most popular water heating system and offers a ready reservoir of hot water ranging from 20 to 80 gallons. It operates by releasing hot water from the top of the tank when you turn on the hot water tap. Cold water enters the bottom of the tank, replacing the hot water to ensure the that the tank is always full. Storage water heater fuel sources include natural gas, propane, fuel oil and electricity.

Energy can be wasted even when a hot water tap isn’t running since water is constantly being heated in the tank. This is called standby heat loss. Some of these water heater storage models have a heavily insulated tank, which significantly reduces standby heat losses and lower annual operating costs. Look for models with tanks that have a thermal resistance, or R-Value, of R-12 or R-25.

Proper insulation depends on many factors including fuel type, climate, local building code requirements and safety issues, especially concerning the combustion of gas- and oil-fired water heaters. It’s recommended to have a qualified plumbing and heating contractor install your storage water heater.

Before buying a new water heater, consider the following:

  • Size and first hour rating
  • Fuel type and availability
  • Energy efficiency and costs

The lowest-priced storage water heater may be the most expensive to operate and maintain over a lifetime, while an oversized unit, although alluring, may carry a higher purchase price and increased energy costs due to higher standby energy losses.

Tankless Water Heaters 

Tankless water heaters are also known as demand-type or instantaneous water heaters, which provide hot water only as needed. These do not produce the standby energy losses associated with conventional storage water heaters and can save you money. Although gas-fired tankless water heaters tend to have higher flow rates than electric ones, they can waste energy if they have a constantly burning pilot light. This can sometimes offset the elimination of standby energy losses when compared to a storage water heater. In a gas-fired storage water heater, the pilot light heats the water in the tank so the energy isn’t wasted.

The cost of operating a pilot light in a tankless water heater varies from model to model. If you purchase a water heater that uses a standing pilot light, you can always turn it off when it is not in use to save energy. Also consider models that have a intermittent ignition device (IID) instead of a standing pilot light. This device resembles the spark ignition device on some gas kitchen ranges and ovens.

Tankless water heaters heat water directly without the use of a storage tank. When a hot water tap is turned on, cold water travels through a pipe into the unit. Either a gas burner or an electric element heats the water. As a result, tankless water heaters deliver a constant supply of hot water and you don’t need to wait for a storage tank to fill up with enough hot water. however, the water heater’s output limits the flow rate.

Typically, tankless water heaters provide hot water at a rate of 2-5 gallons per minute.  Gas-fired tankless water heaters produce higher flow rates than electric ones. However, even the largest gas-fired model cannot supply enough hot water for simultaneous, multiple uses in large households. For example, taking a shower and running the dishwasher at the same time can stretch a water heater to its limit. You can install two or more tankless water heaters connected in parallel for simultaneous demands of hot water to overcome this problem. You can also install separate tankless water heaters for appliances that use a lot of hot water in your home.

Other applications for demand water heaters include the following:

  • Booster for appliances , such as a clothes washer or dishwasher
  • Booster for a solar water heating system
  • Remote bathrooms or hot tubs

The initial cost of a tankless water heater is greater than that of a conventional storage water heater , but tankless water heaters will typically last longer and have lower operating and energy costs, which could offset its higher purchase price. Most tankless water heaters will have a life expectancy of more than 20 years and have easily replaceable parts that extend their life by many more years. In contrast, storage water heaters last 10-15 years.

Before buying a tankless water heater, consider the following:

  • Size
  • Fuel type and availability
  • Energy efficiency
  • Costs
Heat Pump Water Heaters

Heat Pump water heaters use electricity to move heat from one place to another instead of generating heat directly. Therefore can be two or three times more efficient than conventional electric resistant water heaters. heat pumps work like a refrigerator in reverse in order to move the heat.

While a refrigerator pulls heat from inside a box and dumps it into the surrounding room, a stand-alone air source heat pump water heater pulls heat from the surrounding air and dumps it into a tank to heat water, at a higher temperature.

Heat pump water heaters require installation in locations that remain in the 40°-90°F range year-round and provide at least 1,000 cubic feet of air space around the water heater. Cool exhaust air can be exhausted to the room or outdoors. Heat pump water heaters will not operate efficiently in a cold space because they tend to cool the space they are in. You can also install an air source heat pump system that combines heating, cooling and water heating. These combination systems pull their heat indoors from the outdoor air in the winter and from indoor air in the summer. Because they remove heat from the air, any type of air-source heat pump system works more efficiently in a warm climate.

Before buying a heat pump water heater, consider the following:

  • Size and first hour rating
  • Fuel type and availability
  • Energy efficiency
  • Overall costs

Heat pump water heaters generally have higher initial costs than conventional storage water heaters. However, they have lower operating costs, which can offset their higher purchase and installation prices.

Solar Water Heaters

* (ACE HI PLUMBING, HEATING & AIR, INC does not repair or install solar water heating systems)

Solar water heaters are also called solar domestic hot water systems. This can be a cost effective way to generate hot water for your home. They can be used in any climate, and the fuel they use – sunshine – is free.

There are two types of active solar water heating systems – direct and indirect circulation systems. Direct circulation has pumps that circulate household water through the collectors and into the home. They work well in climates where it rarely freezes. Indirect circulation has pumps that circulate a non-freezing heat-transfer fluid through the collectors and heat exchanger. This heats the water that then flows into the home. This is more common in climates prone to freezing temperatures.

There are two types of passive solar water heating systems. Integral collector-storage passive systems work best in warmer climates. And then there’s a thermosyphon system which water flows through the system when warm water rises as cooler water sinks and also this type of system generally costs more.

Most solar water heaters require a well-insulated storage tank and have an additional outlet and inlet connected to and from the collector. In two-tank systems, the solar water heater preheats water before it enters the conventional water heater. In one-tank systems, the back-up heater is combined with the solar storage in one tank.

Solar water heating systems almost always require a backup system for cloudy days and times of increased demand. Conventional storage water heaters usually provide backup and may already be part of the solar system package. A backup system may also be part of the solar collector, such as rooftop tanks with thermosyphon systems. Since an integral-collector storage system already stores hot water in addition to collecting solar heat, it may be packaged with a tankless or demand-type water heater for backup.

Before buying a solar water heating system, consider the following:

  • Estimate the cost and energy efficiency of a solar water heating system
  • Evaluate your site’s solar resource
  • Determine the correct system size
  • Investigate local codes, covenants and regulations
  • Understand the various components needed
    • Heat exchangers
    • Heat-transfer fluids
Tankless Coil & Indirect Water Heaters 

Tankless coil and indirect water heaters use a home’s space heating system to heat water. They’re part of what’s called integrated or combination water and space heating systems.

A tankless coil water heater provides hot water on demand without a tank. When a hot water faucet is turned on, water is heated as it flows through a heating coil or heat exchanger installed in a main furnace or boiler. Tankless coil water heaters are most efficient during cold months when the heating system is used regularly but can be an inefficient choice for many homes, especially for those in warmer climates.

Indirect water heaters are a more efficient choice for most homes, even though they require a storage tank. An indirect water heater uses the main furnace or boiler to heat a fluid that’s circulated through a heat exchanger in the storage tank. The energy stored by the water tank allows the furnace to turn on and off less often., which saves energy. If an indirect water heater is used with a high-efficiency boiler and well-insulated tank, can be the least expensive means of providing hot water, particularly if the heat source boiler is set to “cold start.”

ACE HI PLUMBING, HEATING & AIR, INC. can help you to find the right water heater for your home. If you need to schedule an installation call us today at 970-667-0300. We provide 24-hour emergency service in the Northern Colorado Area.

Rinnai Tankless Water Heaters

If you have questions, live within the Northern Colorado area and need to schedule a water heater repair or installation, Call ACE HI PLUMBING, HEATING & AIR today at 970-667-0300. We provide 24/7 emergency services in Loveland, Fort Collins, Berthoud, Longmont, Johnstown, Milliken, Greeley and Estes park.

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Rinnai Tankless Water Heaters

Innovative technology that provides an endless supply of hot water whenever and wherever it’s needed, even for simultaneous uses at multiple fixtures including:

  • Showers
  • Baths
  • Sinks
  • Clothes washers
  • Dishwashers

Rinnai’s tankless water heaters are designed for efficiency with technology that features compact copper heat exchangers to provide maximum efficiency and easily meets ENERGY STAR qualifications and uses up to 40% less energy than a traditional tank. This product also has a longer lifespan, of about 20 years or more, compared to a conventional storage tank water heater and has recyclable parts, meaning less waste in landfills, and produces less CO2 and NOxthan conventional tank water heaters

These tankless water heaters are able to save energy by operating only at times when hot water is needed rather than having a storage tank to heat and reheat water. This helps to save on energy and your utility bills.  There is no use of an electronic ignition device with a standing pilot light that is continuously using energy. The tankless technology achieves maximum energy efficiency and helps to conserve natural resources.

Rinnai tankless water heaters also come in multiple sizes to customize your efficiency and can be installed on any wall or even in compact spaces, including non-traditional spaces including crawl spaces, basements and attics. You can use these in any size of home including in mobile or manufactured homes. Rinnai tankless water heaters come in small sizes, at 18.5″ x26″ x 10″ or smaller.

If you have a larger home and have a higher demand, Rinnai supports a feature, EZConnect, that allows you to link two units with a simple cord. For even larger applications, your installer can place multiple units in parallel.


How does a Rinnai Tankless Water Heater Work?

When turning on the hot water tap, cold water enters through the water heater from the inlet pipe at the bottom of the unit. The PC board is then signaled to activate the flame igniter or ignition. A combustion fan is turned on to allow oxygen into the burner to ignite the flame as the gas control valve opens at a low frequency. Once an adequate flame is present, the igniter stops sparking and begins the next sequence of operation all in a matter of seconds.

Water is heated as it passes through the coils of the pipes of the home to the water fixture where the hot water is needed at that time. For condensing models, the water is preheated as it passes through a secondary stainless steel heat exchanger, capturing any extra heat before it escapes into the vent system.

The gas valve and the blower automatically adjust the incoming gas and oxygen to meet the water heating demands and adjusts as needed to ensure the temperature set point is maintained. The water heater can use a smaller flame and less gas if the demand for hot water is small. If the demand is greater, the flame is able to expand across the width of the entire burner to heat more hot water. The user can choose their desired temperature with the digital controller for ultimate comfort and safety.

When the hot water tap is turned off , Cold water then stops entering the water heater and the flame diminishes. The combustion fan continues to operate at a low speed for a short period of time which allows the exhaust of any leftover combustion gasses.

How will Rinnai’s Tankless Water Heaters be affected by the new DOE standards?

Rinnai’s Tankless Water Heaters are steps ahead in delivering the ultimate energy efficient performance and already meet the minimum DOE energy factor standards of .82, so the changes will have no direct impact. With the size and design of Rinnai’s products, tankless water heaters may be installed in a wider variety of locations, including places where the new, larger conventional storage water heaters will no long fit.

For water heaters with storage tanks 30 to 50 gallons in size, the increase in the minimum standards will trigger an increase in the insulation needed, resulting in a larger tank diameter. In some cases, 2 inches or more, which will make equipment replacement more problematic because the same size of tank may not fit in the same location. Tanks above 55 gallons will now need to be high efficiency condensing units requiring an electrical outlet to power the unit, different venting, and also a means to drain the condensation. These changes add up to an increased overall cost of storage tank water heaters, including an increase in manufacturing cost coupled with potentially higher installation costs.

Gas Storage Water Heaters
Volume Current Federal Minimum Federal Minimum from 2015
114L (30gal) .61 .63
151L (40gal) .59 .62
190L (50gal) .58 .60
246L (65gal) .55 .75
284L (75gal) .53 .74

New 2015 NAECA Water Heater Standards

New 2015 NAECA Water Heater Standards

National Appliance Energy Conservation Act and its History

The National Appliance Energy Conservation Act of 1975 (NAECA) was enacted to help create uniform appliance efficiency standards at a time when individual states were creating their own standards. The NAECA established a conservation program for major household appliances, however no real standards came into existence until the 1980s when appliance manufacturers realized it was easier to conform to a uniform federal standard then individual state standards.

The National Appliance Energy Conservation Act of 1987 amended the Energy Policy and Conservation Act and was introduced and supported by democratic Senator Bennett Johnston, Jr. from Louisiana in January 1987. The new amendments to the act established minimum efficiency standards for many household appliances. These standards were put in place to ensure that manufacturers were building products that are at the maximum energy efficiency levels are that are technically feasible and economically justified.

Department of Energy Water Heater Standards for 2015

The U.S. Department of Energy (DOE), as part of the NAECA issued Final Rule energy efficiency mandates in April 2010. As a result, on April 16, 2015, the new requirements call for higher Energy Factor (EF) ratings on virtually all  residential gas, electric, oil and tankless gas water heaters. The NAECA rulings are important to customers because they reduce energy usage and save money all year long. According to the U.S. Department of Energy website, standards mandatory in 2015 will save approximately 3.3 quads of energy and result in approximately $63 billion in energy bill savings for products shipped from 2015-2044. These far-reaching new requirements will have important impacts on water heating manufacturers, distributors, installers and consumers.


What this means for homeowners

These regulation standards will be mandatory in Northern Colorado, which includes all of Larimer, Boulder and Weld counties.

The new water heaters have to accommodate the higher insulation r-values, or thermal resistance, which will make the water heater typically 1-2 inches taller and up to 2 inches wider. In some cases, the water heater will have to be relocated to operate properly, or mitigate noise.

While the operating cost of the new water heaters will be less because of their increased energy efficiency, it is likely that the maintenance costs will increase because of a more complex design, and the integration of electronics, blowers, fans condensers, etc.

The new water heaters are expected to be 20-30% higher than the price of a current water heater. In some cases, other installation costs may be required to adapt to the new water heater’s size and efficiency installation requirements.


To find out more information or to schedule a new water heater installation, call ACE HI PLUMBING, HEATING & AIR today at 970-667-0300. We service the Northern Colorado areas including Loveland, Fort Collins, Berthoud, Longmont, Windsor, Greeley, Evans, Johnstown, Milliken and Estes Park.

Direct Vent vs. Power Vent Water Heaters

Direct Vent vs. Power Vent Water Heaters

There are many variations of water heaters making it overwhelming and difficult for homeowners to know which type of water heater would be the best choice for their home. Here we will go over the two most popular water heater types – direct vent and power vent. The difference between the two water heater types is combusted from the burner to the vent system. A direct vent water heater vents these combustion gases to the atmosphere , while a power vent water heater removes them with the aid of a powered venting fan.


Direct vent

Direct vent water heaters are very popular in the Fort Collins, Colorado area. In a direct vent water heater, fuel is burned and the heat from the combustion process is used to heat the water. The exhaust gases are then transferred to the outside of the home via the exhaust pipe or chimney.

Direct venting works because heated air is lighter than cool air and in turn will rise naturally due to the difference in buoyancy between the hot and cold air. This is a simple system that works well when the exhaust gases can be vented vertically. No extra power is needed and in turn, the overall hot water heating costs are lower.

Power vent

A power vent water heater uses a fan or blower to assist in the removal of exhaust gases from the hot water heater. If the water heater is installed in a location the doesn’t have access to a vertical vent or chimney, a power vent water heater mat be your only option. Exhaust gases can be pushed through horizontal exhaust pipes with the use of a fan or blower.

The main benefit of a power vent water heater is the ability to locate the water heater away from a chimney. If there is no chimney available, horizontally venting the water heater to the outside through inexpensive venting pipe instead will also benefit the homeowner by saving money. This type of water heater is more common in certain areas of Northern Colorado such as Loveland, Fort Collins and Berthoud areas.


A power vent water heater will cost more initially due to extra equipment needed such as the fan and blower. Also, you will need to run a power line to the fan which will also add to the cost. Another downside to this is that the blower portion of the water heater will need electricity to operate and will increase your hot water heating costs throughout its lifetime.

Finally, it is known for some people to complain about the sound of the fan running when the hot water heater is operating. While it’s probably only a minor concern, it’s something that should be seriously considered. Proper installation can help to eliminate, or minimize most of this.

Whichever water heater is right for you, depends on your situation with respect to access to a vertical vent (vent stack) path or chimney. To get more information about what type of water heater would be best suited in your home, call Ace Hi Plumbing, Heating & Air today at 970-667-0300.

Troubleshooting Water Heater Pilot Lights – Ace Hi Plumbing, Heating & Air

Troubleshooting  Water Heater Pilot Lights

Important: Before troubleshooting any pilot light problems, keep in mind that pilot flame is always ON and the flame should be mostly blue. If it is yellow it needs adjustment. Also, make sure the tank is completely filled with water before lighting the pilot light.

 Pilot Light Will Not Stay Lit

 It is crucial that you read the manufacturer instructions carefully to prevent problems with the water heater pilot light; How to Maintain Gas Water Heaters and How to Light it. It is also important to understand when troubleshooting pilot light problems that gas heaters are equipped with the safety elements. There are many factors that can cause a water heater to not stay lit.

Here are some of the most common reasons:

  • Thermocouple goes out
  • Gas utilities being turned off
  • Air temperature
  • Lack of oxygen
  • Defective gas control valve
  1. All gas water heaters use pilot lights to ignite the main gas burner used to heat the tank reservoir. The pilot light plays a significant safety role as it ensures that any gas supplied to the main burner is ignited and not allowed to accumulate prior to the main burner is immediately ignited and not allowed to accumulate prior to combustion, thus creating a potentially dangerous explosion.

A thermocouple is a sensor used to measure temperature under a wide variety of temperature ranges and conditions and designed automatically to shut off the unit when the flame is not present or extinguished for any reason. The thermocouple stands guard over the functioning of the pilot light. It accomplishes this by continually monitoring whether the pilot light is burning and by providing an immediate “fail safe” by shutting down gas supply system when the pilot lights fail to burn, before uncombusted gas can accumulate at the burner head.

If the thermocouple connection is loose, tighten it. It should be embedded in the flame and tighten correctly, first hand, tighten and then use the wrench for an additional 1/4 turn. If you have the faulty thermocouple, replace it with a new one. The gas control valve should be creating at least 10 millivolts.

2. If there is no gas, or gas pressure is too high or low, check with your utility company.

3.  The air present in gas lines could prevent the pilot light from lighting. Purging the air from a gas line should be performed by a professional.

4.  Replace the thermostat, or gas control valve, if the inner elements are faulty or if the thermostat ECO switch is open.

Gas water heaters use two different elements to control the gas flow to the water heater. The gas cut-off valve is situated on the gas line leading into the water heater. The gas line feeds from the cut-off valve to the gas control valve assembly.

The gas control valve is part of the gas burner control module. This unit operates to control gas flow to the pilot light and as a thermostat by turning the gas to the burner off after water reaches the desired temperature. A thermocouple sensor detects when the temperature of the water drops and sends an electrical impulse to the thermostat control. The Thermostat causes the burner to light and bring the temperature of the water back up to the temperature setting on the thermostat.

Pilot flame is too large

The Main reason a pilot light is too large is if the gas pressure is too high. There is nothing you can do about this problem except to gall the gas utility company and check with them. The wrong size of the pilot burner orifice is another reason.

 Pilot flame is too small 

You may experience the flame being too small if the gas pressure is too low. Check with your utility company about this problem. Also, the pilot light tube’s orifice might be clogged with the dirt found in the gas line. Some elements you can clean, but if there’s dirt on the incoming gas line, you should notify your utility distributor and check with the gas technician about installing the dirt trap in the gas line. If you have the wrong pilot burner, replace it with the correct one.

 Pilot light will not light

One reason why you don’t have hot water is because the burner did not ignite. This happens when the pilot light does not light. Listed below are a few reasons.

  1. If the pilot light is clogged, you should clean or replace it.
  2. Faulty Piezo igniter. The water heater uses the piezo igniter to light the main gas burner and when pressed, it releases the electric spark. The spark gap is factory set. When Troubleshooting the light problems, it is recommended to test it first. Turn the gas OFF to the water heater and press the piezo igniter. Once pressed, the electrode should release the spark.
  3. Check to make sure the wire connections are properly tightened.
  4. Be sure that the electrode is not broken and replace it if it is.
  5. If there is soot and/or carbon deposits on the pilot light, you should clean the tip of the electrode from the dirt, rust and other deposits by using a dry cloth and sandpaper.
  6. No gas or faulty gas valve does not release the gas.

Pilot light goes out due to condensation  

Most of today’s water heaters will produce a certain amount of condensate. If there is excessive condensation, it will effect the light and extinguish it. In this extreme case, condensate is running down the flue tube and is dripping on the main burner, resulting in the pilot outage.

Pilot light goes out due to improper venting or air supply 

Improper venting will cause the pilot light outage on direct vent gas water heaters . Even a down draft from a ceiling fan or if there is a draft at the bottom of the unit, can blow out the pilot light. If there is a restriction on the fresh air delivery, find the reason and remove the obstructions. The proper air supply should be delivered when the unit is installed in a small, confined place. If there is wind blowing directly into the DV vent, it may cause the pressure imbalance.