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Thermostatic valves are a simple and reliable control solution requiring neither electricity nor control air. An example of application is automatic control of water temperature in cooling systems.The...
Code number selector
Approvals & certificates (3)
What is a kv-value?
Answer: Capacity / kv - value: – Specifies how many m3/hour (capacity) water is passing through the valve at a differential pressure at 1 bar. – Is a result of all the different constants coming from shape of orifices, units etc. which are reduced to one new constant, the kv - value. – Is used to calculate capacity: – ? = density (kg / m3) – ?P = P1 - P2 Q = k v ?P [m3 / h]
I need a spare part for my product. Do you have that?
Answer: Please see the relevant accessories sections in our internet product catalogue, which will list all available spare part options for your market.
Where can I find approvals and certificates for Danfoss products? E.g. do you have a PED certificate for KP7W?
Answer: You can find product approvals and certificates for all our products on our internet website. Follow this link to search for documents either by product or by authority: http://www.danfoss.com/BusinessAreas/IndustrialAutomation/Documentation/Approvals+and+Certificates.htm
Do Danfoss products comply with RoHS directive (Restriction of Hazardous Substances)?
Answer: Yes, all declarations of conformity, including RoHS and WEEE, can be found in our internet product catalogue. Look up the product of your interest and find the relevant document either under the Literature link or the Approvals & Certificates link.
I'm looking for a Danfoss code number and I have not found it in any catalogues?
Answer: Som code numbers are not available for all markets, or it may have been replaced by another number. To resolve the issue, please contact your nearest Danfoss office: http://www.danfoss.com/Contact/Worldwide/
Could I send you a Danfoss part for repair?
Answer: Danfoss does not have repair departments locally. For warranty or complaints issues, please contact your nearest Danfoss sales office and they will tell you how we handle these issues in your area.
Do you have a device that cools a heating system on rising temperature?
Answer: Yes, you should use the AVTA thermostatic valve. It opens at rising temperature and is therefore a good solution for a cooling function.
Which valve should I choose for an aggressive fluid?
Answer: You should look for a valve in DZR brass for slightly aggressive media and a stainless steel valve for aggressive media. Please note that the seal material should also be appropriate the media.
Can you supply the Danfoss valve with the type designation WKB?
Answer: Please get in touch with Danfoss Water Controls, who handles this valve type.
How do I remedy reduced functionality of an AVTA after placing the sensor in a immersion pocket?
Answer: To ensure thermal conductivity between the sensor and the immersion pocket wall, it is recommended to use heat-conductive compound, available as an accessory under the code number 041E0110 (5 g) or 041E0111 (800 g).
Is it possible to use AVTA for protecting bio-mass boilers?
Answer: Yes, AVTA is a great solution for biomass boilers above 100 kW, preventing overheating of the boiler. In case of smaller boilers, we recommend the purpose-designed bio-mass valve BVTS.
What does it mean that thermostatic valves are proportional and self-acting?
Answer: Proportional means that on sensor temperature change, the cooling water flow quantity change is proportional. This correlation is kept up to 85% of valve capacity. Self-acting means that thermostatic valves operate without the supply of external auxiliary energy such as electricity or compressed air. It is a very important advantage of thermostatic valves because even at breakdowns in the power supply, the valve will still function, e.g. keep cooling the application.
Is it possible to replace a copper capillary tube with a stainless steel version?
Answer: No, unfortunately elements with stainless steel capillary tube are not available, but we recommend using a thermostatic element with stainless steel armor, protecting the capillary tube''s entire length.
Does an AVTA valve contain any hazardous parts or substances?
Answer: No, an AVTA is free from any hazardous components and is in conformity with the RoHS directive.
Is it necessary to dismantle AVTA valve from the application to replace the thermostatic element?
Answer: No, the bellows element can be replaced without uninstalling the valve from the application. This action can be done even with the water in the system.
Can an AVTA valve be used with glycolic water?
Answer: Yes, the AVTA can be used with glycolic water with up to 30% of glycol.
Can I use an AVTA thermostatic valve to regulate air temperature?
Answer: Yes you can use it, but it will effect the response time and accuracy of the regulation, because normally the valves are used in liquids like water or oil.
Can you deliver your products worldwide?
Answer: Yes, we have own distribution centre across the world, working together with more than 100 distributors and agents. You can see your nearest distributor or Danfoss office here: http://www.danfoss.com/Contact/Sales_and_Services/
Do you have a complete catalogue showing all your products?
Answer: Our internet product catalogue is the most extensive information source: http://www.danfoss.com/Products/Categories/ Besides these products, Danfoss also produces customer-specific products and solutions that are not visible in the catalogue. Please contact your nearest Danfoss office to discuss your needs and how we can meet them.
Can you deliver products exclusively made for us?
Answer: Yes, we have the possibility to develop products that are unique for one customer subject to individual agreements. The products may differ in appearance, technical features or packaging. Please contact us to discuss your requirements.
Which distribution channels does Danfoss use?
Answer: Danfoss makes use of different channels, including distributors, to suit the markets' needs. An increasing number of our customers use our web ordering and EDI e-commerce solutions.
Can I review your stock online?
Answer: Yes. By using Danfoss web-ordering, you can check product availability. Please contact Danfoss to get access to web-ordering.
Where can I find technical drawings of Danfoss products?
Answer: Dimension and function drawings of our products are often part of the products'' technical leaflets. In our internet product catalogue (http://www.danfoss.com/Products/Categories/), find the product of your interest, then follow the Literature link to see available items.
Can high differential pressure across an AVTA valve influence its functionality?
Answer: Thermostatic valves type AVTA work independent from media differential pressure up to 10 bar. Pressure above this level can influence valve functionality. AVTA are controlled only by an application temperature.
Where do I direct commercial or technical questions?
Answer: Danfoss worldwide sales and services is available here: http://www.danfoss.com/Contact/Sales_and_Services/ Your nearest Danfoss office will be able to answer your question, or have it directed to the appropriate expert.
Do you have local stock?
Answer: This depends on the country and product concerned. Our logistics are set up to achieve competitive and reliable delivery performance for our customers.
Why is the sensor mounting position so important for AVTA with universal charge?
Answer: The internal design of the universal charge sensor requires special mounting position - with the red line on top. Also the sensor must not be orientated upwards. The reason is that the sensor is filled with a mixture of liquid and gas and the end of the capillary tube inside the sensor has to be in the liquid phase.
Where can we find your data sheets?
Answer: All relevant literature, including technical brochures, are available on our Web site: http://www.danfoss.com/BusinessAreas/IndustrialAutomation/Documentation/Industrial+Automation+Literature.htm
Do you have local websites in my language?
Answer: Yes, please see http://www.danfoss.com/ and then use the "Local sites" option in the top right-hand corner.
Is it possible to place orders online?
Answer: Yes, you can place orders and access order information online. Please contact Danfoss to get access to web-ordering. You can see the benefits of Danfoss web-ordering at http://www.danfoss.com/Products/ebusiness/
Does Danfoss operate globally?
Answer: Yes. More than 100 Danfoss sales companies and more than 100 agents are spread across the world, making Danfoss nearby, always.
Is Danfoss a German company?
Answer: No, it is a globally acting group with headquarters in Denmark.
Can I use an AVTA valve for heating purposes ?
Answer: AVTA is designed for cooling systems in industrial applications. However if you remove the 8 screws that fix the valve body and assemble in the reverse position, you will be able to use the valve for heating purposes, always respecting the temperature that the bulb is specified for. For heating systems, we recommend the Danfoss valve AVTB, designed for this application and obtainable through the Danfoss Heating Division.
What is the difference between the AVTA and AVTB ?
Answer: The AVTA valve opens at rising temperature (cooling application). The AVTB, available from Danfoss Heating Division, is the opposite of the AVTA, and is used for heating applications, so it opens when temperature is falling.
My AVTA valve's sensor with universal charge is only half immersed in the medium. How does this influence the valve's functionality?
Answer: We recommend placing sensor in such a way that the whole of its surface is in contact with the medium. Generally the less sensor is immersed in water the slower and less accurate it reacts on temperature change.
What is off-set for thermostatic valves?
Answer: It is the temperature on sensor that corresponds to 85% of valve opening. Above that number, the link between controlled temperature and water flow is no longer linear and temperature control is less precise.
What is hysteresis of an AVTA valve?
Answer: Hysteresis depends on the sensor filling. The best score is for universal and mass charge. When the correct valve size is chosen. hysteresis can be on a level of ±2 °C. This is because of the floating nature of the spindle “hanging” in the diaphragms and only centered by lubricated O-rings in the valve covers.
What is the AVTA valve's reaction time on temperature changes?
Answer: Reaction time depends on two factors: Type of the charge and whether sensor is in contact with liquid media or air. Examples of reaction time for AVTA with mass/universal charge: 3-4 seconds - sensor in water, at increasing temperature, middle range. 216 seconds - sensor in air 0.5 m/s, at increasing temperature, middle range. 156 seconds - sensor in air 1.0 m/s at increasing temperature, middle range. For adsorption charge reaction time is longer than for other two fillings.
Which AVTA valve should I use when the ambient air has H2S, destroying the capillary tube?
Answer: Hydrogen Sulfide H2S is very toxic and has severe effect on copper elements. We recommend the armoured version of capillary tube. Please see our internet catalogue for relevant code numbers.
What is the compatibility of AVTA body with deionized water, corrosive for metals?
Answer: Deionized water is an aggressive medium and can have bad influence on brass housing of the valve. DI water can destroy brass material, extract metals (zinc) from brass and pollute water. Very high grade DI water will erode brass fast (around 6 months) and low quality DI will give a slow gradual attack on the brass. We recommend using a stainless steel version of the AVTA valve.
Is there any temperature range preset made for the WVTS valve?
Answer: No, there is no preset done in the factory for WVTS valve. You have to adjust the element to meet your demand for opening temperature.
Can you send me a 3.1 certificate for a valve already delivered?
Answer: The inspection certificate 3.1 involves test results that shall be carried out during production process for the specific valve. For valves already produced, we are therefore not able to issue this certificate. Therefore, when ordering, please specify the need for the certificate.
Permissible working pressure for the WVTS valve is 10 bar. What will happen if WVTS will be installed in application where pressure is maximum 16 bar?
Answer: If the pressure is higher than the allowed, it is likely that the permanent influence shortens the life period of the internal parts of the WVTS valve. In such cases, we recommend using 2 AVTA valves in parallel connection instead of one WVTS. The AVTA can operate at 16 bar and thus be used without problems.
How do I see the production date of an AVTA valve?
Answer: The production date stamp is placed on the valve body. It contains 3 digits: The first two are related to production week and the third one to production year.
The pilot unit for WVTS valve is supplied with white plastic washer - is it only packaging protection to be thrown out?
Answer: The white plastic washer is essential part of the valve – without this component, WVTS loses its functionality. Please remember to check presence of this part during assembly of pilot unit and WVTS valve body.
Is it necessary to install a filter ahead of thermostatic valves?
Answer: We always recommend installing a filter type FV in the pipe system ahead of valves, especially in cases when the medium could be contaminated or include dirt particles. A dirt filter should be always installed ahead of the FJVA valve, which has a small-diameter bypass in the valve body.
Are AVTA, FJVA and WVTS valves UL or CSA approved?
Answer: No, they are not approved as they don''t have any electrical components, and therefore an approval is not needed.
My WVTS 80 valve has 8 holes for flange connections, but the technical brochure shows only 4. Is the product wrong?
Answer: WVTS sizes 50 and 65 have 4 holes for flange connections. Bigger valves WVTS 80 and 100 are fitted with 8 holes.
For thermostatically operated valves, are there any requirements to the cooling water temperature?
Answer: The only requirement is that the cooling water temperature should be less or equal to the setting temperature. If the cooling water temperature is close to that point, then more capacity is necessary to cool down the process medium. We may in this case recommend a bigger valve size than in cases when the cooling water temperature is lower. How to select proper size of the valve depending on cooling water temperature is shown in the data sheet.
My AVTA valves is noisy - why?
Answer: If the noise comes from the valve body, it may mean that the opening degree of the valve cone is too small. This gives a high velocity over the valve seat which can generate noise.
How does AVTA react to cooling oil as a medium?
Answer: We recommend using NBR diaphragms for oil as cooling medium. NBR diaphragms are available as accessory 003N0445, 003N0446, 003N0447 (see the technical brochure or our Internet product catalogue).
Can AVTA be used for a mixture of alcohol and water?
Answer: As we do not know exact type and composition of alcohol, we suggest forwarding above information to manufacturer of the mixture, who can assure proper functionality with NBR and EPDM seal materials.
Is it possible to order a WVTS valve with other charge than universal?
Answer: No, WVTS is available only with universal charge.
Are thermostatic valves AVTA, FJVA, WVTS normally closed or normally open valves?
Answer: Thermostatic valves valves are NC - normally closed. They open on rising application temperature.
The maximum sensor temperature of AVTA (Regulation range 0-30°C) is 57°C. Can the minimum sensor temperature be down to -40°C?
Answer: There is no problem with that. Danfoss internal standards demand our products resistance to such temperature due to transport reason.
Where can I get the technical brochure for AVTA valves?
Answer: Please see our internet product catalogue. Select "Thermostatic valves", then "AVTA", then look for the "Literature" link.
How do I select the right size AVTA valve?
Answer: First you must know the flow rate of water required, the regulation temperature at the sensor, and the allowable pressure differential across the valve. With this information refer to the AVTA technical brochure for instructions and tables which will help you select the correct valve. If you do not know the water flow rate required, there is a table which will help you determine it, but you will need to know the required capacity of heat removal in refrigeration tons (TR) or in KW.
Are Danfoss AVTA valves UL listed?
Answer: AVTA valves are passive non-electrically operated devices which do not require UL listing.
What is difference between AVTA and FJVA valves?
Answer: FJVA is similar to AVTA, except it operates without a remote sensor element connected by capillary tube. Instead the FJVA valve reacts to temperature of water flow through the valve body itself.
Can the sensor element of AVTA valves be installed in any orientation?
Answer: This depends on the sensor element used. Only the adsorption charge type sensor can be installed in any direction. The mass charge and universal charge types must be installed with orientation according to AVTA technical brochure.
Can an AVTA valve be installed in any orientation?
Answer: Yes, but be sure to observe the flow direction arrow on valve body, and install accordingly.
How do I set temperature on AVTA valve?
Answer: Turn the adjusting knob clockwise for higher temperature, counterclockwise for lower temperature. To calibrate, use thermometer to measure temperature near sensing point.
Does the Kv value correspond to the value of the flow?
Answer: Yes, the Kv value we mention in product catalogues and technical brochures gives the capacity of water with the differential pressure of 1 bar measured in cubic meter per hour : Q=Kv*v(?P/?) unit m3/hour; ?P=differential pressure; ?=density. Q=flow Kv=constant ?P=in pressure - out pressure ?=? of the fluid
Where can I find some technical information about your products?
Answer: Please see our online product catalogue: http://www.danfoss.com/BusinessAreas/IndustrialAutomation/Product+catalogue/IA+product+catalogue.htm
Can I get an AVTA with ATEX approval?
Answer: Using no electricity, ATEX approval is unnecessary with AVTA - we can use all AVTAs in Eex atmosphere. Declaration from factory is available.
What do I need to know to select the right product?
Answer: The following are the basics for most products used in industrial environments: Application - Pressure - Temperature - Medium - Connection
Can I get quality control plans/process flowcharts/material specifications/FMEA for Danfoss products?
Answer: No, this is confidential information which cannot be shared outside Danfoss. Rare exceptions are cases of special legal agreements between Danfoss and the other company.
Can you send me literature, brochures or catalogues on your products?
Answer: We appreciate your interest and will happily send you an overview of our offering in print. Please contact your local Danfoss office or e-mail us on email@example.com, describing your interest and application.
I placed an order through e-commerce. Could you please check the delivery dates and inform me the earliest possible delivery?
Answer: Delivery dates are supplied in the e-commerce system and based on Danfoss standards. If the confirmed delivery date is not acceptable, please contact Danfoss through e-mail or telephone.
How do I adjust the temperature on an AVTA valve?
Answer: You have to use the setting knob on the upper side of the valve. Position 1 is the minimum temperature of the specific range position, and 5 is the highest. If you need a very accurate figure, you should check the temperature setting with a thermometer.
Can I download product approvals & certificate from the Danfoss websites?
Answer: Yes, in our internet product catalogue, all product approvals & certificates are listed. If you are unable to local a specific document, please e-mail or call us.
Can I order just the capillary tube for an AVTA?
Answer: Yes, you can order the complete thermostatic element for each type of AVTA. See or internet product catalogue for options.
Which media can Danfoss products be used with?
Answer: The answer depends on the materials in contact with medium for the particular product. This information can be found in the technical brochure / data sheet for the product. We have products designed specifically to handle particular media, including drinking water, oil, air, petrol, steam and more. If in doubt, please contact your nearest Danfoss office.