Radson International



Why does my radiator produce no (or insufficient) heat ?

  1. It has not been fully bled or the air vent has been installed at the wrong location.
  2. The installation pressure is too low; for normal residential installations this has to be 1.5 to 2 bars, for high-rise buildings 2 to 5 bars.
  3. The radiator has been installed incorrectly :
    1. Check the installation and settings of the taps, thermostatic heads and shutoff valves.
    2. If supply and return are exchanged at Integra radiators, this might results in noises, or banging of the thermostatic valve body.
    3. For radiators with a building height of 600mm or more (at compact or CLD ) : if supply is connected at the bottom left of the radiator and return at the bottom right (or the other way around), this might cause no or insufficient heat.
  4. Not enough flow or discharge from the pump (check the position of the radiator):
    1. You can increase the pump rate or you can install a heavier pump.
    2. For vertical radiators a minimum flow of 150 l/h and a discharge of 3m water column is required, especially if they are mounted the other way around with the central connection pointing upwards.
    3. Radiator part is too small when used with foot valve with adjustable bypass.
    4. Has the radiator been added to an existing installation or connected to a separate collector?
  5. If you are working with a one-pipe-system, and the radiator is the last one in the circuit, the supply temperature might be too low. You can readjust the radiator part by using a foot valve or you can change the Kv settings of the thermostatic valve body.
  6. The Kv settings of the thermostatic valve body are incorrect.
  7. An incorrect thermostat head has been used (stroke length does not match the thermostatic valve body); this can be tested by removing the thermostat head.
  8. The radiator is blocked. You can test this by exclusively using the radiator for the installation, by closing all others.
  9. The thermostatic valve body is blocked because of impurities in the installation.
  10. For model 33: if the front panel is cold but the back panels feel warm, this means that the middle panel has not been sheared.
  11. Radiators with a glued face plate (verticals or horizontals) produce a little bit less radiant heat, but more air convection. The feel of radiant heat through the front plate is less compared to a radiator without front plate. So reaching the set room temperature takes a bit longer . You can manually feel between the panels of the radiator to determine whether it heats up sufficiently.
  12. Check whether the chosen connection conforms to the choice options as indicated in the Radson Technical Price List. You can download this on the website, if you do not have it: www.radson.com  select country and language  downloads  price lists  technical price list
  13. The radiator has to be warm around the supply, around the return about 10 to 20 degrees colder, due to the flow in the radiator.

Frozen Radiators

It happens every winter: a radiator that is unprotected may freeze due to unexpected and very cold outdoor temperatures. This does not just happen at job sites but also in residential buildings.

How does this occur?

Rooms that are unheated or rarely heated during winter are the first rooms "at risk" (e.g., a porch, garage, unused room, barn, basement, hall and even a living room that is unheated during winter in an attempt to save heating costs).

Temperatures in rooms that are unheated can drop below freezing, even in residential buildings. The water filling the radiator turns to ice and the radiator will literally crack under the immense pressure of the frozen water. This not only results in a broken radiator that needs to be replaced, but water damage caused by the melted ice that flows from the now-damaged radiator.

How can this be prevented ?

  1. Ensure the radiators have thermostatic valves installed that regulate the supply of hot water, provided the valve is not fully closed, but is in the position indicated by a star. However this alone is insufficient.
  2. Ensure the requested temperature at night does not go too low. Most people set their home’s temperature for their living room. It is possible that the room temperature is achieved if this is programmed to 15°, however the thermostat will now order the boiler to temporarily stop warming. This is a dangerous moment for the other radiators in the other rooms. It is possible that the room temperature will remain at 15° the entire time, while the temperature in the porch goes below freezing, causing the water in the radiator to freeze.
  3. Do not change the installation of the radiators, the boiler or thermostats while you are absent (if this is not too expensive, or only for a couple of days).
  4. Do not think the heat produced in the other rooms will automatically go to the rooms that are not heated. In other words, do not expect that this will occur, but instead ensure that the required min. temperature is set in every room (on every moment of the day or year).

How to spot a frozen radiator ?

  1. The upper water channel is deformed throughout the entire length of the radiator due to the conversion of water into ice.
  2. The steel between the welding points will swell due to the ice.
  3. The steel sheeting at the upper welding points or at the connection box will have cracked in most cases. There is no doubt if you see any of these signs: the radiator has frozen.

Cracks in Certain Heated Floors

Certain causes are possible:

  1. There are no expansion seams: surfaces that are not rectangular or square have to be divided into rectangular or square spaces. Surfaces larger than 40 m2 and/or longer than 8 meter have to divided too such that the total surface is smaller than 40m2. In this case, ensure that the proportion between the longest side and the shortest side is not greater than 2:1! The door openings also require an expansion seam underneath the closed door. The expansion seams have to be filled with silicone or a special profile. If this is not the case, the various floor surfaces cannot move freely.
  2. The heating procedure has not been properly executed : always wait at least 21 days after covering the pipes with a screed (for screeds based on cement) or 7 days (for anhydride screed) before starting the heating procedure. The first heating period lasts 3 days with a supply temperature of 25°. After that, 4 days with a max. temperature of (45° to 50°)
  3. The temperature of the circles is too high : the maximum water temperature is 50°. An automatic setting monitors this limit, but your contractor will add another protection that will stop the circulation pump in case the setting should cease to function.

Sounds in the Radiator

  1. Click, clack, click, clack: This is caused by a bad connection; the supply and the return are inverted.
  2. Tsh-sh-sh-sh: A water supply that is too great at the level of tap is the cause of a pressure level that it too high
  3. Tick tick tick: In most cases, this is caused by tension where the piping and brackets touch the floor, the wall or other materials. The brackets or other suspension systems without plastic caps can also create this sound. These sounds can move through the entire installation.

My Radson boiler is defective

Radson manufactures and sells panel radiators, bathroom radiators, design radiators and floor heating (in Belgium, Luxembourg and the Netherlands). The Radson boilers are not part of the selection. Please contact the company below for more information regarding after-sales service for boilers:

Kontichsesteenweg 17-2630 Aartselaar (Belgium)
+32 3 887 20 60 - fax: +32 3 887 01 29