Radiant Floor Heating with Heat Pump
www.arcticheatpumps.comPerhaps the best matched heating system for any heat pump is radiant floor hydronic heating. The reason is simple, the lower the design temperature the ...
Radiant floor heating using heat pump? - GreenBuildingAdvisor
www.greenbuildingadvisor.comWhat some people call a "geothermal" system is more properly called a ground-source heat pump. A ground-source heat pump can be connected to a ...
Ecowarm Radiantboard & Hydronic Heat Pumps
ecowarmradiantheat.comThat is efficiency and capacity to any water-to-water heat pump! Radiant Heat Installed In Shower Wall & Ceiling. (Right) Ceiling Installation (Left) Floor, ...
How to Choose the Right Heat Pump for In-Floor Heating
www.nordicghp.comHi Rob, A geothermal heat pump would be an excellent heat source for radiant in-floor heating, particularly our W Series heat pump. How much you ...
Air-to-water heat pumps in complementary hydronic systems
www.hpacmag.comThis sets the table for use of hydronic heat emitters such as radiant floors, radiant walls and radiant ceiling panels, panel radiators, ...
Air to Water Heat Pump Design - 123 Zero Energy
www.123zeroenergy.comHeat Pump Design Guide ... A small hydronic pump can move the same amount of energy as a larger forced air fan ... Radiant Floor Heating +Domestic Hot Water.
Using Heat Pumps in Hydronic Floor Heating | Benefits
www.heatpumpshq.comA hydronic radiant floor heating system uses tubing below the floor to produce a warm environment. This is all done with a hot liquid that passes through the ...
Radiant Heating | Department of Energy
www.energy.govHydronic radiant floor systems pump heated water from a boiler through tubing laid in a pattern under the floor. In some systems, controlling the flow of hot ...
Mini-Split Heat Pumps Vs. In-Floor Radiant - Artemisia
www.artemisiacabin.comWe compare mini-split heat pumps to an air-to-water radiant heat floor system.
Air-To-Water Heat Pumps with Radiant Delivery in Low Load ...
www.nrel.govthrough a radiant floor, fan coils, or radiators. The same heat pump can also be used to provide domestic hot water. Efficiency advantages are gained by ...
The Closed System | | DIY Radiant Floor Heating
www.radiantcompany.comIntroduction. Contents [hide]. Introduction; “Radiant Ready” closed systems; The ALPHA circulator pump; High Volume Systems ...
The Best Systems · Our Radiant Heating Systems ... - Radiantec
www.radiantec.comIt is one single system that operates in two different and distinct ways. When floor heat is called for, the pump comes on and water flows out of the tank, ...
Underfloor Heating & Hydronic Radiant Floor Heating
www.climatemaster.comA radiant (also known as hydronic) floor heating system uses a series of pipes underneath the floor to heat a room. The entire surface of the floor radiates ...
Hybrid Heat Pumps (Pulsed-Air + Hydronic) | The Master Group
www.master.ca3 product(s) available in Hybrid Heat Pumps (Pulsed-Air + Hydronic) sorted ... Geothermal Heat Pump 7 Series WaterFurnace ... Capable of radiant floor heat)
Inverter air-to-water heat pumps | 2021-05-11 - Plumbing ...
www.pmmag.comWhere hydronic radiant heating performance is concerned, there are multiple methods of installing your radiant panels for floors, walls and ...
Can a radiant floor heat a whole home? - Ecohome
www.ecohome.netRadiant heat can be a complete heating solution for a home, but to do so successfully there are considerations. Any radiant floor heating system ...
Common Problems with In-Floor Radiant Heating - Advantage ...
www.advantageairtech.comRadiant floor heating has become very popular with homeowners for some obvious ... or circulator pumps – If you have a hot water hydronic radiant system, ...
Best Radiant Floor Heating System for Residential Homes in ...
waterlooenergy.comRadiant In-Floor Heating Systems uses a hydronic system to pump heat through your floor. Heated floors are energy efficient and provide ...
Infloor Heating Systems Powered by Geothermal Energy
www.infloor.comI highly recommend it.” “Water-to-water geothermal heat pumps work great with correctly designed hydronic radiant flooring systems,” said Michael Willburn, ...
Using a Hydronic Radiant Floor Heating System with a Water ...
www.geojerry.comWater-to-water geothermal heat pumps work great with correctly designed hydronic radiant floor systems. The temperature of the air in the home will be ...
How to save money with Hydronic Radiant Cooling - Hydro ...
hydrosolar.caAlso Radiant Floor Heating system using low temperature hot water as a fluid heat transfer is way more energy efficient than forced air system ...
Electric vs. Hydronic Radiant Heat Systems - The Family ...
www.familyhandyman.comHeated floors, often called radiant floors or a radiant heat system, ... However, because they usually involve a boiler, a pump and gas lines, ...
Radiant Heating & Snow Melting Solutions - Watts
www.watts.comOur product line includes various heating, floor warming, and snow melting products and applications. When it comes to tubing and fittings or controls and ...
Radiant Floor Heating 101 - Bob Vila
www.bobvila.comRadiant floor heating, popular in new construction, has become a ... A chiller or geothermal heat pump must be used to supply the cold water ...
Radiant Floors and Ceilings Make Geothermal Even Better
www.phcppros.comI was recently speaking on the phone with a major heat pump manufacturer about heating and cooling trends. By and large, the best ...
Radiant Heating 101 | Nelson Mechanical Design Incorporated
nmdgreen.comRadiant heating uses hot water – usually in the range of 85 F to 120 F – generated by a boiler, an air to water heat pump, a geothermal water to water heat ...
Underfloor heating - Wikipedia
en.wikipedia.orgRelating specifically to underfloor heating, thermal comfort is influenced by floor surface temperature and associated elements such as radiant asymmetry, ...
Radiant Heating Systems in Courtenay, BC - Temprite Climate ...
www.tempriteclimatesolutions.comRadiant heating, or in-floor heating, is a type of heating that uses hot water ... increased inefficiency of a heat pump as temperatures reach sub-freezing.
Definitive Guide to Radiant Floor Heating Systems - Innovative ...
innovativebuildingmaterials.comRather than pumping air directly beneath your floor, the heated air is circulated through a series of tubes, similar to how water is used. The difference is ...
Geothermal and Radiant Heat | Warmboard, Inc.
www.warmboard.comGround source geothermal heat pumps can be a practical solution for those who ... pump, and the required water temperature for the radiant floor heating is ...
Combining minisplit heat pump with radiant heat floors - Houzz
www.houzz.comOk so I want to combine a mini split heat pump into my home that will have hydronic radiant heated floors(oil boiler). I am located in New England.
Analysis of the Use of Radiant Floor Heating as a Cooling ...
www.mdpi.comWhen a heat pump is used as the heat source, there is the opportunity to use floor heating as a cooling system by reversing the operating mode ...
HydroShark® Modular Panel System for Radiant Floor Heating
www.stiebel-eltron-usa.comHydroShark Radiant Floor Heating Systems use only premium components and quality assembly. They use only the best pumps, controls, and components.
HVAC and Radiant Floor Heating Archives - Ontario Home ...
buildersontario.comOn June 2, 2019 / HVAC and Radiant Floor Heating / 2 Comments. Geothermal heat pumps are gaining some traction with homeowners interested in saving money, ...
How Much Does Radiant Floor Heating Cost? - HomeAdvisor
www.homeadvisor.comYou may choose to install radiant heating in a smaller area of your home or individual room which costs between $1,717 and $6,047 on average, or from $6 to $20 ...
Radiant Floor Heating For Commercial & Industrial Buildings
www.pmengineer.com4) Electrical companies instigated promotional programs to introduce the heat pump. Beginning in the late 1980s, radiant floor heating made ...
Should I go with an air source heat pump or electric radiant ...
greenhomeguide.comI am concerned that a heat pump will not be able to heat in the ... and run a heat pump with back-up coil or electric radiant floor heat?
Radiant Floor Heating | Clarence-Rockland, Hawkesbury ...
www.fernanddenis.comWith radiant flooring, people lose less heat to cold surfaces like their floors, making them more comfortable. As a result, the room temperature can often be ...
Frequently Asked Questions About Radiant Heat
www.dannyheineman.comHow much should a typical radiant floor heating system cost? ... for my radiant heating system? Most maintenance items center on the pumps and boilers.
How to model GSHP with radiant floor heating in OpenStudio?
unmethours.comI design a small house, using OpenStudio 1.7.2, with a ground source heat pump (GSHP) for space heating, cooling, and hot water use.
Geothermal Heat Pump | WaterFurnace
www.waterfurnace.comThese units are designed for heating and cooling water in applications like radiant floor heating, domestic hot water, and snow/ice melt. They can also be used ...
Heating System Controls - Pexheat
www.pexheat.comWatts Radiant 2 Circuit SS Manifold, Actuators, Zone Pump, Motorized Mix Valve ... Pexheat is a full-service floor heating design and sales company.
All You Need To Know About Hydronic Heating Systems
www.climatecare.comRadiant heating is more comfortable than traditional forced-air heating because we typically heat the floor, which is the largest surface in the ...
Using geothermal heat pump for a floor radiant heating system
www.pexuniverse.comGeothermal heat pumps may be effective when used for a radiant heating system to heat a house; the heat pump supplies hot water, while PEX tubing transports it ...
Radiant Floor Heating with Heat Pump
www.arcticheatpumps.comPerhaps the best matched heating system for any heat pump is radiant floor hydronic heating. The reason is simple, the lower the design temperature the ...
Radiant floor heating using heat pump? - GreenBuildingAdvisor
www.greenbuildingadvisor.comWhat some people call a "geothermal" system is more properly called a ground-source heat pump. A ground-source heat pump can be connected to a ...
Ecowarm Radiantboard & Hydronic Heat Pumps
ecowarmradiantheat.comThat is efficiency and capacity to any water-to-water heat pump! Radiant Heat Installed In Shower Wall & Ceiling. (Right) Ceiling Installation (Left) Floor, ...
How to Choose the Right Heat Pump for In-Floor Heating
www.nordicghp.comHi Rob, A geothermal heat pump would be an excellent heat source for radiant in-floor heating, particularly our W Series heat pump. How much you ...
Air-to-water heat pumps in complementary hydronic systems
www.hpacmag.comThis sets the table for use of hydronic heat emitters such as radiant floors, radiant walls and radiant ceiling panels, panel radiators, ...
Air to Water Heat Pump Design - 123 Zero Energy
www.123zeroenergy.comHeat Pump Design Guide ... A small hydronic pump can move the same amount of energy as a larger forced air fan ... Radiant Floor Heating +Domestic Hot Water.
Using Heat Pumps in Hydronic Floor Heating | Benefits
www.heatpumpshq.comA hydronic radiant floor heating system uses tubing below the floor to produce a warm environment. This is all done with a hot liquid that passes through the ...
Radiant Heating | Department of Energy
www.energy.govHydronic radiant floor systems pump heated water from a boiler through tubing laid in a pattern under the floor. In some systems, controlling the flow of hot ...
Mini-Split Heat Pumps Vs. In-Floor Radiant - Artemisia
www.artemisiacabin.comWe compare mini-split heat pumps to an air-to-water radiant heat floor system.
Air-To-Water Heat Pumps with Radiant Delivery in Low Load ...
www.nrel.govthrough a radiant floor, fan coils, or radiators. The same heat pump can also be used to provide domestic hot water. Efficiency advantages are gained by ...
The Closed System | | DIY Radiant Floor Heating
www.radiantcompany.comIntroduction. Contents [hide]. Introduction; “Radiant Ready” closed systems; The ALPHA circulator pump; High Volume Systems ...
The Best Systems · Our Radiant Heating Systems ... - Radiantec
www.radiantec.comIt is one single system that operates in two different and distinct ways. When floor heat is called for, the pump comes on and water flows out of the tank, ...
Underfloor Heating & Hydronic Radiant Floor Heating
www.climatemaster.comA radiant (also known as hydronic) floor heating system uses a series of pipes underneath the floor to heat a room. The entire surface of the floor radiates ...
Hybrid Heat Pumps (Pulsed-Air + Hydronic) | The Master Group
www.master.ca3 product(s) available in Hybrid Heat Pumps (Pulsed-Air + Hydronic) sorted ... Geothermal Heat Pump 7 Series WaterFurnace ... Capable of radiant floor heat)
Inverter air-to-water heat pumps | 2021-05-11 - Plumbing ...
www.pmmag.comWhere hydronic radiant heating performance is concerned, there are multiple methods of installing your radiant panels for floors, walls and ...
Can a radiant floor heat a whole home? - Ecohome
www.ecohome.netRadiant heat can be a complete heating solution for a home, but to do so successfully there are considerations. Any radiant floor heating system ...
Common Problems with In-Floor Radiant Heating - Advantage ...
www.advantageairtech.comRadiant floor heating has become very popular with homeowners for some obvious ... or circulator pumps – If you have a hot water hydronic radiant system, ...
Best Radiant Floor Heating System for Residential Homes in ...
waterlooenergy.comRadiant In-Floor Heating Systems uses a hydronic system to pump heat through your floor. Heated floors are energy efficient and provide ...
Infloor Heating Systems Powered by Geothermal Energy
www.infloor.comI highly recommend it.” “Water-to-water geothermal heat pumps work great with correctly designed hydronic radiant flooring systems,” said Michael Willburn, ...
Using a Hydronic Radiant Floor Heating System with a Water ...
www.geojerry.comWater-to-water geothermal heat pumps work great with correctly designed hydronic radiant floor systems. The temperature of the air in the home will be ...
How to save money with Hydronic Radiant Cooling - Hydro ...
hydrosolar.caAlso Radiant Floor Heating system using low temperature hot water as a fluid heat transfer is way more energy efficient than forced air system ...
Electric vs. Hydronic Radiant Heat Systems - The Family ...
www.familyhandyman.comHeated floors, often called radiant floors or a radiant heat system, ... However, because they usually involve a boiler, a pump and gas lines, ...
Radiant Heating & Snow Melting Solutions - Watts
www.watts.comOur product line includes various heating, floor warming, and snow melting products and applications. When it comes to tubing and fittings or controls and ...
Radiant Floor Heating 101 - Bob Vila
www.bobvila.comRadiant floor heating, popular in new construction, has become a ... A chiller or geothermal heat pump must be used to supply the cold water ...
Radiant Floors and Ceilings Make Geothermal Even Better
www.phcppros.comI was recently speaking on the phone with a major heat pump manufacturer about heating and cooling trends. By and large, the best ...
Radiant Heating 101 | Nelson Mechanical Design Incorporated
nmdgreen.comRadiant heating uses hot water – usually in the range of 85 F to 120 F – generated by a boiler, an air to water heat pump, a geothermal water to water heat ...
Underfloor heating - Wikipedia
en.wikipedia.orgRelating specifically to underfloor heating, thermal comfort is influenced by floor surface temperature and associated elements such as radiant asymmetry, ...
Radiant Heating Systems in Courtenay, BC - Temprite Climate ...
www.tempriteclimatesolutions.comRadiant heating, or in-floor heating, is a type of heating that uses hot water ... increased inefficiency of a heat pump as temperatures reach sub-freezing.
Definitive Guide to Radiant Floor Heating Systems - Innovative ...
innovativebuildingmaterials.comRather than pumping air directly beneath your floor, the heated air is circulated through a series of tubes, similar to how water is used. The difference is ...
Geothermal and Radiant Heat | Warmboard, Inc.
www.warmboard.comGround source geothermal heat pumps can be a practical solution for those who ... pump, and the required water temperature for the radiant floor heating is ...
Combining minisplit heat pump with radiant heat floors - Houzz
www.houzz.comOk so I want to combine a mini split heat pump into my home that will have hydronic radiant heated floors(oil boiler). I am located in New England.
Analysis of the Use of Radiant Floor Heating as a Cooling ...
www.mdpi.comWhen a heat pump is used as the heat source, there is the opportunity to use floor heating as a cooling system by reversing the operating mode ...
HydroShark® Modular Panel System for Radiant Floor Heating
www.stiebel-eltron-usa.comHydroShark Radiant Floor Heating Systems use only premium components and quality assembly. They use only the best pumps, controls, and components.
HVAC and Radiant Floor Heating Archives - Ontario Home ...
buildersontario.comOn June 2, 2019 / HVAC and Radiant Floor Heating / 2 Comments. Geothermal heat pumps are gaining some traction with homeowners interested in saving money, ...
How Much Does Radiant Floor Heating Cost? - HomeAdvisor
www.homeadvisor.comYou may choose to install radiant heating in a smaller area of your home or individual room which costs between $1,717 and $6,047 on average, or from $6 to $20 ...
Radiant Floor Heating For Commercial & Industrial Buildings
www.pmengineer.com4) Electrical companies instigated promotional programs to introduce the heat pump. Beginning in the late 1980s, radiant floor heating made ...
Should I go with an air source heat pump or electric radiant ...
greenhomeguide.comI am concerned that a heat pump will not be able to heat in the ... and run a heat pump with back-up coil or electric radiant floor heat?
Radiant Floor Heating | Clarence-Rockland, Hawkesbury ...
www.fernanddenis.comWith radiant flooring, people lose less heat to cold surfaces like their floors, making them more comfortable. As a result, the room temperature can often be ...
Frequently Asked Questions About Radiant Heat
www.dannyheineman.comHow much should a typical radiant floor heating system cost? ... for my radiant heating system? Most maintenance items center on the pumps and boilers.
How to model GSHP with radiant floor heating in OpenStudio?
unmethours.comI design a small house, using OpenStudio 1.7.2, with a ground source heat pump (GSHP) for space heating, cooling, and hot water use.
Geothermal Heat Pump | WaterFurnace
www.waterfurnace.comThese units are designed for heating and cooling water in applications like radiant floor heating, domestic hot water, and snow/ice melt. They can also be used ...
Heating System Controls - Pexheat
www.pexheat.comWatts Radiant 2 Circuit SS Manifold, Actuators, Zone Pump, Motorized Mix Valve ... Pexheat is a full-service floor heating design and sales company.
All You Need To Know About Hydronic Heating Systems
www.climatecare.comRadiant heating is more comfortable than traditional forced-air heating because we typically heat the floor, which is the largest surface in the ...
Using geothermal heat pump for a floor radiant heating system
www.pexuniverse.comGeothermal heat pumps may be effective when used for a radiant heating system to heat a house; the heat pump supplies hot water, while PEX tubing transports it ...
How to Install Heated Floors - The Home Depot
www.homedepot.com
Radiant Floor Heating Basics - DIY Network
www.diynetwork.comInstalling a Radiant Floor System · 1. Excavate the area to be heated. · 2. Add a layer of insulation to create a base over which the rest of the floor system ...
Installing Radiant Floor Heat - This Old House
www.thisoldhouse.comHydronic radiant floors are heated by warm water pumped through plastic tubing. Other components in a typical hydronic system include a boiler or water heater, ...
Pros & Cons of Radiant Floor Heating - Warmup
www.warmup.comInstallation aside, you will still need to call out a qualified electrician to connect the system to your power supply, this may take a few ...
Radiant Floor Heating 101 - Bob Vila
www.bobvila.comAs a starting point, materials and mechanical equipment for installing hydronic radiant heat in a 2000 sq. ft. home cost about $3,500 or $1.75 ...
How to Install In-Floor Radiant Heat - The Family Handyman
www.familyhandyman.com
Radiant Floor Design Tips | 2019-11-04 | phcppros
www.phcppros.comWhat you need to know to design and install a successful radiant floor heat project. · Perform a room-by-room heat loss load calculation.
Radiant Heating | Department of Energy
www.energy.govRadiant Floor Heat ... radiant floors. You can further categorize these types by installation. Those that make use of the large thermal mass of a concrete slab ...
Your Guide to Radiant Floor Heating: The Pros and Cons
sebringdesignbuild.comElectric radiant heat is provided by electric under-floor heating cables. · Hydronic radiant floor heating system, with the help of a boiler, ...
Definitive Guide to Radiant Floor Heating Systems - Innovative ...
innovativebuildingmaterials.comThe cost to install a hydronic system is among the lowest of the three types. Starting costs are around $10 a square foot for dry installations and can go as ...
The Floor Joist Installation | | DIY Radiant Floor Heating
www.radiantcompany.comInstalling floor joists A floor joist installation presents some unique challenges ... Check out our video Radiant Floor Heat Tubing Installation in Floor ...
How Much Does Radiant Floor Heating Cost? - HomeAdvisor
www.homeadvisor.comYou may choose to install radiant heating in a smaller area of your home or individual room which costs between ...
Under Floor PEX Radiant Heat "How To Install" Examples
www.houseneeds.comSee different methods of installing PEX Under Floor Radiant Heat. PEX underfloor heating systems. Review Installing PEX Tubing from Radiant Floor heating ...
Emerging installation trends for electric radiant floor heating
www.pmmag.comWith a typical floor heating installation, the installer would need to first embed the heating elements in a layer of thinset or self-leveling ...
9 Easy Steps to Install Electric Radiant Floor Heating
www.warmlyyours.com9 Easy Steps to Install Electric Radiant Floor Heating · Step 1: Start with a floor plan. · Step 2: Order your materials. · Step 3: Test your ...
Radiant Floor Heating in Bathrooms -- Is It Worth It? - New Life ...
www.newlifehi.comIs it worth it to install radiant floor heating under your bathroom floor? In most instances, yes. Find out why.
Best Flooring for Radiant Heat Systems - The Spruce
www.thespruce.comRadiant floor heating can be installed under a surprisingly large number of floor coverings. Yet due to the amount of heat generated by these ...
Warmboard-S Radiant Heating Panels
www.warmboard.comThe thickness of the 7-ply plywood panel also means you can install it as a ... With Warmboard radiant heat floor panels, you require less tubing, ...
Residential radiant heating - Uponor
www.uponor.comResidential radiant heating. Simple-to-install systems, flawless performance and enhanced IEQ ... Uponor PEX radiant floor heating installation ...
6 Things To Consider Before Installing Radiant Floor Heating
www.floorheatingsystemsinc.comRadiant heating systems are most commonly installed under floors, so you will probably have to tear up your existing floor to install this ...
Can I Add Hot Water Radiant Floor Heat to My Home
savehomeheat.comAs with the baseboard heaters installed in different parts of your home, radiant floor heating is setup as an independent, thermostatically ...
How to Install Radiant Floor Heating on an Existing Concrete ...
todayshomeowner.comFind out how to install a radiant floor heating system on top of an existing concrete slab under a wood laminate floor.
What To Know About Radiant Floor Heating - From the Forest
www.fromtheforest.comEven electric radiant floor heating, which is cheaper and easier to install, will still have a price of about $10 to $20 per square foot. You ...
2021 Radiant Floor Heating Cost | Cost to Install Heated Floors
www.fixr.comThe national average range to install radiant floor heating in the home is between $20,000 and $40,000, with most homeowners paying around ...
Top Five Radiant Floor Heating Installation Methods
www.qualifiedremodeler.comKnobbed mats are becoming more a more widely used option for radiant floor heating due to the ease of use for tubing installation. The mats come ...
Radiant Floor Heating - Concrete Network
www.concretenetwork.comInformation on radiant floor heating, including benefits of concrete floor heat, lower heating and energy costs, warmth, design and installation tips, ...
Dry or Wet? Radiant Heating System Choices | PM Engineer
www.pmengineer.comAs the hydronic radiant floor heating industry has grown in the United States, so has the number of methods of radiant installation.
Need a cheap to install radiant flooring system - Green ...
www.greenbuildingtalk.comI have been researching a new home build like crazy, one of many things to decide is what type of system to run radiant floor heating.
How to Properly Install Radiant Floors - Insta Panels
www.instapanels.caRadiant heating can be installed above or below subfloors. If installing under a subfloor, prepare the area by removing existing flooring. Always install ...
How to Install Radiant Floor Heat in an Existing Home
homeguides.sfgate.comRadiant heat is a method of heating the floor by using electrical wiring or heated water, with the heat then transferred upward thorough the floor and into ...
How to install in floor heating - MP Global Products
www.mpglobalproducts.comQuietWarmth is a flexible radiant heating film that is installed below floating floor materials to create Warm comfortable floors.
Zurn Radiant Heating Design and Application Guide
www.zurn.comfor design and installation of radiant floor, ceiling and wall systems. For the purpose of clarity in communication concepts, this manual is conceptual.
Install Radiant Floor Heating | HGTV
www.hgtv.comWant to install radiant floor heating? HGTVRemodels gives you the flooring lowdown on HGTV.com.
ThermoFloor® Radiant Floor Heating Installation - ThermoSoft
www.thermosoft.comThermoFloor® Radiant Floor Heating Installation · 1. Roll out your radiant floor warming pads and arrange to fit your heated area. · 2. Fill in non-heated areas ...
How to Install Radiant Floor Heat | LoveToKnow
homeimprovement.lovetoknow.comThere are several ways to get a heated floor, including radiant heat provided by electric cables. Install these radiant heat cables yourself whether in a ...