PEX Tubing with oxygen barrier is used for radiant floor heating, ice/snow melting projects and baseboard/radiator heating applications. It is also commonly used for supply and return lines to boilers and fan coils.

What kind of PEX is used for floor heating?

1/2 Inch PEX Tubing accounts for the majority of Residential Radiant Heat installations and should be used in most slab, overpour, or joist underfloor heating applications. 5/8 Inch PEX and 3/4 PEX pipe are generally reserved for large commercial and snow-melt applications.

Can you run PEX in concrete?

Can PEX be used under a concrete slab? Yes, PEX pipe can be installed under a concrete slab. Since PEX pipe is supplied in coils, installation can be completed in one continuous length without the need for extra fittings. PEX pipe can also be encased within a slab, which is commonly used for radiant floor heating.

What is the maximum length that 1/2 PEX radiant floor?

Various references give different suggested values for maximum radiant panel circuit lengths based on tube size. Some give a range for maximum circuit length, such as 250 to 350 feet when using 1/2″ tubing.

What should PEX not be installed in?

PEX can’t be installed in high heat areas. You can’t install PEX in high heat areas like near recessed lighting. This also means you can’t connect PEX directly to a hot water heater, but you can use a connecting material to do this.

How hot can PEX pipe get?

The maximum heat temperature of the PEX tube is 200 degrees. The maximum heat of the PEX can be up to 180 degrees. The PEX tubing has the highest temperature limitation listed in small prints.

How does PEX floor heating work?

In a radiant floor heating system, warm water flows through flexible plastic tubing called PEX that is located underneath the floor or within the concrete slab. The PEX tubing carries the warm water into specific rooms or “zones” to effectively heat people and objects in every corner of the room.

What is the difference between PEX A and PEX B?

Again, the main distinction lies in the manufacturing method, which is what assigns an A, B or C to PEX. PEX A is made using the Peroxide, or Engel, method. PEX B is formed using Silane, or Moisture Cure, method. This is the most common PEX pipe type out there.

Why do I need oxygen barrier PEX?

The “barrier” referred to in PEX tubing is actually an oxygen barrier. This extra layer in your tubing will assure that no oxygen gets into your heating system. Oxygen in your system can be a problem that causes your system components to rust. … Antifreeze can also break down a system with no oxygen barrier.

How far apart should PEX tubing?

PEX tubing is usually installed within a distance of 8″. Closer spacing (usually no less than 4″) can be applied to areas with higher heat loss or floors with lower heat conductivity.

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How much radiant tube do I need?

Generally, for a residential Infloor Heating System® we recommend 3/8″ and 1/2″ tubing. The tube size dictates the flow rate that can be achieved and also indicates the maximum loop length based on the head pressure. We generally recommend 5/8″ and 3/4″ tubing for large commercial and snowmelt applications.

How long can a radiant heat loop be?

SizeMax Loop Length1/2″300 ft.5/8″400 ft.3/4″500 ft.1″750 ft.

How deep does PEX have to be buried?

PEX pipes and all underground piping should be buried at least 12” to 18” below the frost line to protect the pipes from freezing. The frost line refers to the furthest depth underground groundwater begins to freeze, also called the frost depth.

How long will PEX last underground?

PEX has a life expectancy of 40-50 years, made possible by its durable and non-corrosive materials. Burial also reduces sun exposure, which would otherwise degrade the piping. Additionally, PEX tubing materials allow for expansion, making them resistant to freezing/cracking underground.

How long does PEX last in concrete?

PEX has an expected life of 25 to 40 years.

Why is PEX plumbing bad?

Potential chemical leaching is another downside of PEX piping. Due to its chemical composition, the PEX pipe material may leach toxic chemicals including bisphenol (BPA), MTBE, tertiary butyl alcohol (TBA), and others.

How long does PEX pipe last?

Additionally, long-term testing programs on PEX have shown that it has a potential lifespan of more than 100 years. So, while copper systems may have to be re-piped every few years or decades due to corrosion and pinhole leaks, a PEX system can last 10 times longer — or more.

Can rats chew through PEX pipe?

Mice and rats will chew through anything they can, including plastic, so PEX tubing is at just as much risk as the plastic-coated wiring in a car or an HVAC unit. While all rodent damage can be expensive, if rodents chew through a home’s PEX water pipes, the result can be disastrous.

Can I install radiant floor heating myself?

Electric radiant heating works best under tile floors. DIY radiant floor heating can be installed under vinyl, engineered flooring and wood floors as well – though be sure to read the manufacturer’s guidelines.

At what temperature does PEX melt?

Compared to thermoplastic polyethylene, PEX does not melt (analogous to elastomers) and is thermally resistant (over longer periods of up to 120 °C, for short periods without electrical or mechanical load up to 250 °C).

Can you use blue PEX for hot water?

PEX without an oxygen barrier is designed primarily for use in potable water plumbing systems. … The color of PEX does not change any of the tubing’s ratings. There would be no problem, for example, using blue PEX for hot water lines or red PEX for cold water lines.

What pressure is PEX good for?

PEX-a pipe can withstand a burst pressure of around 800 psi (almost two times the requirement for ASTM F876, the standard specification for PEX tubing). So neither the pipe nor the fittings are weak points, making for an extremely high-performing system in domestic water and hydronic piping applications.

How do you know if PEX has oxygen barrier?

It often has a shiny gloss to it, compared to non barrier. Rub it together and it will squeak. If you heat it with a match or torch carefully you may see that EVOH layer start to de-laminate from the tube.

What's the difference between red and blue PEX?

Red PEX pipe carries hot water. Blue PEX pipe carries cold water. White PEX pipe can be used for either hot or cold water.

Can I use oxygen barrier PEX for domestic water?

Most oxygen-barrier PEX does not have the appropriate approval codes for use with potable water and should not be installed in domestic plumbing applications. … Since oxygen from the air can penetrate PEX tubing (even when the PEX is embedded in a concrete slab), an oxygen barrier is needed in most heating systems.

Which PEX connection method is best?

PEX-A, which has the most flexible tubing and best freeze- and kink resistance, is ideal for use with kitchen and bath fixtures. PEX-B is slightly less flexible and less freeze-resistant.

Which brand of PEX is best?

The Engel method or PEX-A is known as the best type of PEX due to its exceeding that of all international standards set for performance. For example, Sharkbite invented a push-fit fitting which utilizes the consumer to connect PEX tubing without the need for any tools.

Will PEX break if it freezes?

Due to its flexibility, PEX has a small margin of expansion under the damaging pressure caused by ice formation. If the weather gets cold enough, PEX pipes can and will freeze like any plumbing. However, PEX may be less likely to rupture as a result of freezing.

How many feet of PEX do I need for radiant heat?

For standard-sized Pex tubes (half-inch or 5/8-inch internal diameter), the circuit length should not exceed 300 feet – which is conveniently the size of the coil supplied by many manufacturers.

How do you size a heated floor?

Subtract the square footage of the cabinets, appliances or plumbing fixtures from the total square footage of the floor. This will give you the actual square footage of the radiant floor heat installation area.

How do you calculate PEX tubing for radiant heat?

Multiply the number of full loops by the recommended length for each loop to obtain the length of tubing needed to construct the heating loops. For example, 975/250 is 3.9, which is rounded to 4 PEX heating loops for a room that is 25 feet wide and 26 feet long.