Always use an extension type thermostat T&P relief valve which permits the end of the thermostat to extend into the top 6″ of the tank.

T&P valvemeaning

Before deciding on radiant floor heating, consider these pros and cons to determine if it’s the best fit for your home and lifestyle:

Whether it’s warming a large addition or a cozy bathroom, radiant heat underfoot invisibly ups the comfort level. Here’s the lowdown on some of today’s most popular systems.

For wood floors, both hydronic and electric systems can be used, but care must be taken to prevent warping. It’s recommended that you keep surface temperatures below 80°F and choose stable wood species.

Your name Your email Subject Your message (optional) In typical fashion, it was a Sunday morning when the dripping faucets in our kitchen began dripping relentlessly, bringing with it the unnerving and unending sound of water dripping into a stainless steel sink. The incident served only to remind me that when things go wrong around the home […]

Your name Your email Subject Your message (optional) The single most important part of your plumbing system. The most valuable knowledge you can have of your plumbing system is knowing how to shut water off to your home. This knowledge is best used in the case of a plumbing emergency. It is also great if […]

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Radiant heating can be used in various areas of your home, but it’s often recommended for smaller rooms, such as the bathroom, kitchen, or entryway. The tiles in these spaces make it the perfect place for radiant heat. However, these systems are also often found in garages and basements.

Radiant heating systems aren’t restricted to the floor. They can be found behind the walls or in the ceiling. For example, a hydronic tubing system can be installed behind the walls of a chilly stairwell to warm up the space. In addition, both hydronic and electric systems can be installed outside and used to melt snow on walkways, driveways, and patios.

In doing so, a small amount of water will also be dispensed onto the floor. Unfortunately, many people mistake this for a leak or a water heater failure, when in fact, it may simply be doing what it is designed to do. If you ever see water on your floor around this area, you should call a plumber right away. The valve may be failing, in which case it should be replaced, or you may have excessive pressure in your tank, which should be tested for.

Controlling your water heater allows you to take full advantage of the efficiency of the storage tank. This allows water to be heated during non-peak hours for use throughout the day. Automatic timers can do the job for you. Properly sized water heaters provide enough hot water to meet your needs round the clock.

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In normal operation of the water heater and T&P valve, no water should be discharged from the valve. A T&P valve that discharges is an indication of an abnormal condition in the system and by discharging, the T&P valve is meeting its designed safety purpose. The causes of discharge can be thermal expansion, excess system pressure, low temperature relief, too high a setting on the water heater, or something in the water heater causing excess temperatures in the heater.

A good indication of thermal expansion is when the T&P valve releases about one cup of water for each 10 gallons of heater capacity with each heating cycle. The T&P valve is functioning properly when it relieves pressure caused by thermal expansion, but frequent relief can build up natural mineral deposits on the valve seat, rendering the valve inoperative. This condition can be addressed by the installation of a Watts thermal expansion tank or other Watts thermal expansion device to protect your system from overpressure caused by thermal expansion. If there is no discharge from the valve, there is no need to replace the valve.

Also, be sure to compare federal Energy guide labels on electric water heaters before you choose one. The Energy guide label will give you the unit’s estimated annual energy cost. A high-efficiency electric water heater costs more than an inefficient one, but you will be paid back through lower electric bills.

Another factor to look for when you’re shopping for a new electric water heater is the amount of built-in insulation it offers. Although this type of water heater generally costs more than one with minimal insulation, you’ll be saving money in the long run by reducing the amount of electricity needed to keep the water hot.

TOH Pro Tip: “Because a tiny nick can cause a malfunction, it’s good practice to test the resistance of any electric radiant system and floor-temperature sensor with a multimeter before and after installation, and after covering it with flooring. Some manufacturers require a log of these tests for warranty purposes.” —Charlie Silva, home builder

Hydronic systems use heated water, which is then pumped through the cross-linked polyethylene (PEX) tubing installed under the floor. These are the most popular option, and they tend to be more cost-effective and energy-efficient than electric radiant heating systems, especially in colder climates.

Important Instructions: Relief Valves and Automatic Gas Shut-Off Devices Combination temperature and pressure relief valves with extension thermostats must be installed so that the temperature-sensing element is immersed in the water within the top 6″ (152mm) of the water storage tank. They must be installed either in the hot outlet service line or directly in a tank tapping. Combination temperature and pressure relief valves that do not have extension elements must be mounted directly in a tank tapping located within the top 6″ (152mm) of the water storage tank. Valves must be located so as to assure isolation from flue gas heat or other ambient conditions that are not indicative of stored water temperature.

Perfect for retrofitting radiant heating systems in existing homes, aluminum transfer plates, such as the Uponor Joist Trak Heat Transfer Panel shown above, attach to the underside of the subfloor, typically in a basement ceiling. They hold the .025-inch-thick PEX tubing and efficiently transfer heat to the floor above.

To ensure proper operation, this valve must be installed by a qualified service technician or licensed plumbing contractor in accordance with these instructions and the local plumbing codes and standards. Repair or alteration of valve in any way is prohibited by national safety standards/local codes.

No shut-off valve shall be installed between the relief valve and tank, or in the discharge line. Valve lever must be tripped at least once a year to ensure that waterways are clear. When manually operating lever, water will discharge through discharge line and precautions must be taken to avoid contact with hot water and to avoid water damage. This device is designed for emergency safety relief and shall not be used as an operating control. If discharge occurs, a licensed contractor must evaluate the system and determine the cause for discharge and correct the cause immediately.

Do not attempt to conduct an inspection on your own. Contact your plumbing contractor for a re-inspection to assure continuing safety. FAILURE TO REINSPECT THIS VALVE AS DIRECTED COULD RESULT IN UNSAFE TEMPERATURE OR PRESSURE BUILD-UP WHICH CAN RESULT IN SERIOUS INJURY OR DEATH AND/OR SEVERE PROPERTY DAMAGE.

WARNING: To avoid water damage or scalding due to valve operation, discharge line must be connected to valve outlet and run to a safe place of disposal. Discharge line must be as short as possible and be the same size as the valve discharge connection throughout its entire length. Discharge line must pitch downward from the valve and terminate at least 6″ (152mm) above a drain where any discharge will be clearly visible. The discharge line shall terminate plain, not threaded. Discharge line material must conform to local plumbing codes or ASME requirements. Excessive length over 30′ (9.14m), or use of more than four elbows or reducing discharge line size will cause a restriction and reduce the discharge capacity of the valve.

TOH Pro Tip: “In-floor radiant can cause wood floors to expand and contract even more than usual. To reduce the chance of the boards cupping, we generally keep them less than 6 inches wide.” —Tom Silva, general contractor

T&P valvepipe

Temperature and pressure (T&P) relief valves used on residential water heaters are typically designed and manufactured to relieve on pressure at 150 psig and on temperature at 210 degrees F. These ASME, ANSI and CSA (AGA) approved relief valves protect the water heater from excess pressures and temperatures by discharging water.

Now that you know what it looks like, and what it does, take the time to check it and make sure yours IS NOT CAPPED OR PLUGGED and that it works properly. You can lift the little handle on it like the picture shows. Sometimes you may need to let the handle snap back down to reseat it properly. If it continues to leak a little, it either has some debris in it or the spring is failing. You can try and open it a few times to remove any debris. If this does not take care of it, call a plumber and have it replaced. Make sure there is a relief tube extending to the floor in case the heater must discharge. This is to prevent accidental scalding. Also, you should not have threads on the bottom of the relief tube. This will ensure that a cap cannot be screwed onto the bottom.

Ceramic tile is the most effective option for radiant floor heating systems as it stores heat and conducts well. However, just about any type of flooring can be used, including wood, concrete, vinyl, linoleum, and even carpeting.

Electric cable with uncoupling membranes, as used in the DITRA-HEAT Uncoupling Membrane, combines heating cables with a waterproof membrane. They’re ideal for tile and stone floors. The membrane allows for movement between the substrate and the finished floor, preventing cracks.

Important: A relief valve functions, in an emergency, by discharging water. Therefore it is essential that a discharge line be piped from the valve in order to carry the overflow to a safe place of disposal. The discharge line must be the same size as the valve outlet and must pitch downward from the valve.

Electric radiant floor heating systems use electric heating cables or mats installed under the floor. As the wires within the cables or mats heat up, the heat is transferred to the room. It’s ideal for smaller areas, such as bathrooms or kitchens, for more localized heating.

A hydronic system tends to cost between $19,000 and $48,000, while an electric floor heating system is often between $19,000 and $36,000.

The energy efficiency of electric radiant heating systems depends on your local electricity rates and flooring type. With proper care and maintenance, they tend to last longer compared to traditional heating options—between 30 and 40 years.

Aluminum oriented strand board (OSB) panels, such as the Warmboard example above, are often used in renovations. They offer a thinner profile than plywood versions, making them suitable for installations where floor height is a concern, and they can easily be screwed over an existing subfloor (or in walls or ceilings). The aluminum layer provides efficient heat transfer from the PEX tubing to the floor surface.

Certain naturally occurring conditions may corrode the valve or its components over time, rendering the valve inoperative. Such conditions can only be detected if the valve and its components are physically removed and inspected.

One great feature of many types of electric water heaters is a non-metallic storage tank. Manufacturers of these tanks warranty them against leakage, eliminating a major cause of early water-heater failure. And if you live in an area with corrosive water, you’ll find this feature to be especially cost-effective.

If discharge occurs, CALL A PLUMBER IMMEDIATELY. Discharge may indicate that an unsafe temperature or pressure condition exists which requires immediate attention by a qualified service technician or licensed plumbing contractor.

T&P valvewater heater

High-efficient boilers, also known as condensing boilers, can achieve over 90% efficiency by condensing flue gases in a heat exchanger. While more expensive upfront, they can significantly reduce long-term energy costs, especially in colder climates, and could result in tax savings.

Your name Your email Subject Your message (optional) Thank you for asking this question about Tankless Water Heaters vs Traditional, Felix. In today’s cost-conscious society, any way to save energy and money should be explored. The cost-saving benefit of replacing a conventional electric water heater with a tankless electric heater is often overestimated. The energy savings from […]

The T&P valve, or temperature and pressure relief valve, is one of the most important safety devices in your home. If the temperature rises above 210 degrees Fahrenheit or the pressure exceeds 150 psi, the valve will open and relieve the pressure inside the tank.

Use standard or extra length extension thermostat which permits the end of the thermostat to extend into the top 6″ of the tank.

Air-to-water heat pumps use electricity to extract heat from outdoor air, even on cold days. They can provide both heating and cooling, making them a versatile choice for year-round comfort. While the initial investment is higher, they offer excellent energy efficiency and can also supply household hot water.

As with most homeowners, you probably only think about your water heater when there is no hot water for your shower or you notice a puddle underneath the water heater. Whatever the reason, when it is time to buy a water heater, consider electric ones because they offer features that ensure a long life and an economical supply of hot water.

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Radiant floor heating systems supply heat similar to how the sun warms the earth. As the heat moves upward, it is evenly distributed across the floor surface. The floor acts as a thermal mass, storing and slowly releasing heat, maintaining consistent temperatures.

Radiant floor heating uses infrared radiation to heat objects and people directly, rather than just the air, providing consistent warmth and comfort. This type of home heating system can be more energy-efficient than traditional forced-air systems, especially in well-insulated homes. Whether you’re considering a hydronic system that circulates hot water or an electric system using heating cables, radiant floor heating can transform your living space into a cozy haven.

Whether it’s warming a large addition or a cozy bathroom, radiant heat underfoot invisibly ups the comfort level. Here’s the lowdown on some of today’s most popular systems.

WARNING: Following installation, the valve lever MUST be operated AT LEAST ONCE A YEAR by the water heater owner to ensure that waterways are clear. Certain naturally occurring mineral deposits may adhere to the valve, blocking waterways, rendering it inoperative. When the lever is operated, hot water will discharge if the waterways are clear. PRECAUTIONS MUST BE TAKEN TO AVOID PERSONAL INJURY FROM CONTACT WITH HOT WATER AND TO AVOID PROPERTY DAMAGE. Before operating lever, check to see that a discharge line is connected to this valve, directing the flow of hot water from the valve to a proper place of disposal. If no water flows when the lever is operated, replacement of the valve is required. TURN THE WATER HEATER “OFF” (see your water heater instruction manual) AND CALL A PLUMBER IMMEDIATELY.

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Hydronic systems typically last 40 to 50 years, with boilers having an average lifespan of 15 to 20 years. Key components of these systems include:

This method of heating suffers minimal heat loss between the surface in the room, unlike ductwork in forced air systems. It also eliminates cold spots that are common with traditional systems.

If installation of a thermal expansion device does not relieve occasional dripping from the T&P valve, then the system pressure should be checked. If system pressure is excessive (typically more than 75 PSI), a Watts pressure regulator should be installed on the incoming water line.

Electric film is designed to float under click-together floors, such as laminate, vinyl, floating tile, or engineered wood, with an underlayment over the subfloor. This option provides gentle, even heat without adding significant height to the floor. One example of electric film is the QuietWarmth Heating Film for Click-Together Floors.

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Radiant floor heating offers a comfortable, efficient, and silent heating solution for many homes. While the initial cost can be higher than traditional systems, the long-term benefits in comfort and potential energy savings make it an attractive option. Consider your home’s specific needs, climate, and budget when deciding if radiant floor heating is right for you.

When water is heated it expands. In a 40 gallon water heater, water being heated to its thermostat setting will end up expanding by approximately 1/2 gallon. The extra volume created by this expansion has to go somewhere or pressure will dramatically increase, such as when water is heated in a closed system.

Aluminum over plywood panels, as in the example above from Warmboard, combines the structural strength of plywood with the heat-conducting properties of aluminum. An aluminum layer runs under the tubing tracks. They’re ideal for new construction or major renovations, adding minimal height to the floor while providing excellent heat distribution.

While you can technically use carpeting, it’s not often recommended as it will decrease the efficiency of your heating system. If you’d prefer rugs or a carpet, choose lower-pile options with thin pads, and aim for a total R-value of 2.5 to improve efficiency.

T&P valvediagram

If you happen to have a pressure reducing valve installed on your main water line, you should pay special attention to this. A pressure reducing valve creates a closed system in your home, and will not allow for thermal expansion. If you have one of these, AND your T&P valve drips occasionally, you may need a thermal expansion tank installed.

Homeowners can expect to pay between $6 and $20 per square foot* for a radiant floor heating system, but the cost can vary depending on the type of system and the area to be heated. Other factors that could impact cost include the type of flooring, installation requirements, site prep, and location.

Basements, garages, and workshops tend to have concrete floors. Hydronic systems can be installed here during new construction, while electric systems can be added to existing slabs.

Less water is wasted going down the drain while you wait for it to get hot, and less energy is wasted heating water that ends up in the pipeline between a faucet and a distant water heater.Overall, an energy-efficient electric water heater is the long-term smart choice for clean, quiet and economical hot water.

Electric peel-and-stick film options, including the QuietWarmth Peel & Stick for Tile and Glue-Down Floors, combine heating elements with a peel-and-stick waterproof membrane, simplifying installation under tile, stone, or glue-down floors. It can’t be used in the shower or with vinyl or linoleum floors.

WARNING: Temperature and Pressure Relief Valves should be inspected AT LEAST ONCE EVERY THREE YEARS, and replaced, if necessary, by a licensed plumbing contractor or qualified service technician, to ensure that the product has not been affected by corrosive water conditions and to ensure that the valve and discharge line have not been altered or tampered with illegally.

Pre-made mats, including the SunTouch TapeMat, come with embedded heating cables that offer easy installation for uniform spaces. However, they can also be cut to fit around obstacles, such as a sink pedestal, and are suitable for various floor types. They come in a wide range of sizes, and some have holes for shower drains. Others use double-sided tape and can be laid over plywood, backer board, or a concrete slab.

Recently, I came across a very dangerous situation with electric water heaters, one that Next Plumbing thinks needs to be addressed. A capped or plugged water heater T&P valve is one of the worst “band-aid” fixes you could ever do in your house. Doing so creates the grounds for a potential bomb or missile in your basement! Although rare, the threat of a water heater explosion is very real. It is crucial to hire an experienced and licensed plumber to fix your water heater instead of using DIY “band-aid” fixes.

Electric water heaters come in a variety of shapes and sizes, and unlike a gas water heater, you don’t have to install gas pipelines or flues. An electric water heater, therefore, can be installed closer to the rooms that use hot water.

Caution: Valve must be installed so that temperature sensing element is immersed in the water within the top 6″ (152mm) of the tank.No valve may be placed between the relief valve and water tank.Install in hot water outlet or in extra side relief valve tapping if one is provided.To avoid water damage, discharge line must be run to a safe place of disposal and must pitch downward.Do not install a shut-off valve, plug, or cap in the valve discharge line.Follow local codes where they vary from these instructions.

WARNING: The discharge from a T&P valve can be very hot. It is very important that all T&P valves be installed properly with a discharge line piped downward to an adequate drain to avoid property damage and to minimize possible human contact. Please read and follow the instructions on the warning tag attached to your T&P valve.