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Radiator Problems and Troubleshooting

Radiators are heat transferors or exchangers used to transmit thermal energy from one medium to another mainly with the intention of cooling or heating. Radiators are usually a source of heat to their environment and generally transfer heat through the convection process and not through thermal radiation. They are commonly used in households for the purpose of heating the premises and work using steam or hot water. Listed below are a few questions answered by the Experts on issues related to radiator problems

Why is my radiator releasing water from the air relief valve?

There could be a few reasons for this. Steam occurs when the return is plugged and if the radiator is close to the boiler. You could start by cleaning the sediments using a pressure hose. The other possibility could be an improperly pitched supply pipe. Also, in a radiator, the pressure is controlled by the “pressuretrol”. Check and ensure that it isn’t set higher than 3 Pound per Square Inch (PSI). Most of the residential “pressuretrols” have a differential which is deducted from the set point.

Can a hot water radiator be converted to a steam radiator?

This is possible. The hot water radiator will most likely have two openings: one on the left and the other on the right. First, you need to remove the plug which is mid way on the opposite side of the steam line. In most cases you will need to drill it and re-tap the hole. You will also need to plug the return opening in the hot water radiator and increase the size tapping for the steam line into the radiator. Tapping on the return line is the wrong location for a steam air valve. Also plug the opening where the old hot water air vent was.

I have tried to remove the air from my six panel radiator but the four middle ones are still cold. I tried bleeding but find that there is water but no air. Do you have any suggestions for my situation?

Bleeding is a term used to describe the removal of trapped air from a hot water system radiator. You could try draining the radiator again and re-filling it slowly, bleeding it simultaneously as you fill. To do so, first turn off the radiator valves and then drain the radiator from one of the connections. Retighten and open one valve and begin to bleed it once the radiator has some water in it. Next, open the other valve. Ensure the heating system is off or it will trap air. The diagnosis is a faulty radiator if this does not work and you will have to get it professionally repaired if it is.

My radiator is spewing out water and rust causing damage to my walls. Why is this happening?

Use the site glass on your boiler to check the water level. It should be approximately half full. Slight movement of water in the site glass is allowed but if it is erratic there could be a problem. In this case, you could first flush the boiler and then fill it with clean water. Another simple and quick solution would be to place a small piece of wood under the feet on the opposite side of the steam pipe.

Is the rapid clicking sound being made by my radiator normal?

Clicking noises are caused when the radiator heats or cools down and thereby expands or contracts respectively. These changes in temperature make the metal rub against the other parts making a clicking noise. Each radiator and its installation can make varying levels of noise. If the clicking is irregular or inconsistent, it is due to expansion and contraction. On a rare occasion if you hear a steady click there could be a defect with the control valve.

My radiator is not heating up. Why?

The most common reasons for the radiator not heating are:

  • Air that is trapped in the line
  • Air that is trapped in the radiator where the top is cooler than the bottom
  • A zone valve or circulator that is faulty

To fix this, you may need to open the radiator bleed valve located at the top of the radiator to bleed air. Close the valve when water starts being emitted from the radiator. Next, check the circulator to make sure it is operating properly and that the motor is running well. Each heating zone at home could have a circulator dedicated to it. Examine each valve to see that it is functioning properly. . Also ensure that the water pipe feels hot up to and beyond the zone valve. In case the valve is faulty or has got stuck, the water pipe will feel hot up till the valve but start cooling down beyond the valve.

Radiators are essential for heating a house especially in harsh environments. Understanding the principle behind the working of a radiator is important to know how to tackle problems as and when they arise. t. Sometimes, the installation could be wrong which causes an issue and at other times there could be more complicated problems such as a leakage or a part suddenly malfunctioning. Minor issues can be resolved on your own if you are comfortable to do so while more serious problems may require professional intervention. For any help, information or guidance required for radiator troubleshooting, consult an Expert for a professional opinion.

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