How to fix a leaky radiator

Are you worried about the deplorable condition of your radiators? A leaking radiator is one of the most common reasons why an installation professional is called in. However, this is not an exaggeration. It is worth remembering that the radiator from which water is poured may soon fail even more seriously and, consequently, stop heating. Don’t know how to overcome a radiator water leak? You don’t want to risk getting your floor wet? Read our latest guide – how to fix a leaking radiator!

Radiator leak – what is the cause?

There are many causes of water leakage from the radiator, but most of them you can diagnose yourself. The most important instrument for diagnosing a heater failure will be… your eye. What causes radiator leak?

  • A leaking radiator valve
    A leaking valve may be the result of a normal valve failure. However, repairing the leaking radiator valve yourself can be difficult, so the best solution is to contact a specialist quickly.

  • Dripping Flare
    If water is leaking on the bottom connection of the heater, loose screws may be the culprit. Try to tighten the screws, remember that if the flare nut is tightened too much, the radiator will pour out even more water.

  • Damage to radiator fins
    It has been known for a long time that rust is one of the toughest enemies of any radiator. If you have noticed rusty coatings on the radiator fins, there is a possibility that the radiator is leaking as a result of leaks.

How to fix a leaking radiator valve - central heating system
how to fix a leaking radiator

Leaking radiator valve – how to replace it?

Were you able to correctly diagnose the cause of the water leakage from the radiator? Time to replace the valve! However, for a safe and effective valve replacement, all water must be drained from the radiator. You probably have no experience with this, so an experienced plumber will be the best solution to the problem.

Replacing the valve is not an expensive procedure, and the visit of a specialist should not take more than an hour of your time. It is true that the specialist will choose the best way to remove the failure, but keep in mind that it is possible to both replace and seal the valve with ordinary Teflon tape.

Leaking radiator – how to seal a radiator yourself?

You can seal small gaps caused by rust with a special glue. If the perforations have grown significantly, and the leaks cannot be sealed with glue – you will have to solder. Another, equally effective, method of removing rust on the radiator is to thoroughly clean the joints between the fins . Also remember to change the radiator seals and regularly check the condition of rust-covered parts. However, sealing and bonding leaks may only be a temporary solution. In this case, it will be necessary to replace the radiator with a new one, which will be much more profitable in the long run.

How to fix a leaking radiator – cast iron radiator leak – damaged ribs

When water is dripping from the radiator at the joints between the fins or from a broken rib, the radiator is rusting. In case of small cracks and cavities, it is possible to supplement them with special adhesives that are waterproof. It is possible to replace individual fins, but the whole process is quite tedious and complicated, so we encourage you to replace the radiator with a new one, when a radiator leaks keeps you awake at night. Dismantling the old radiator can also be problematic, as the usual paint build-up from multiple paintwork on the hooks makes it necessary to use a hammer to remove the radiator. Also, choosing the right radiator can be troublesome because its size should be similar to the old one. In addition, installation requires mounting at the same height as the old radiator. For this reason, it is worth using the help of a specialist. 

What to do when the radiator in the block is leaking?

As a tenant or owner of an apartment in a block of flats, do you have to repair a faulty leaking radiators yourself? The dispute of the cooperative apartment responsible for the repair of the radiator has dragged on for years, but the most recent regulations are relatively clear. The housing cooperative is responsible for repairing radiator leaks in the block. Radiators, as an integral part of the heating system, do not constitute property of the owner of the premises. All costs of replacing or repairing the heater are borne by the housing association.

fix a leaking radiator valve spindle - heating system radiator valve leak
How to fix a leak in a radiator valve

Why heater does not work

The heating season has just started and our radiator won’t work, or worse, it only heats up to half of it. We do not have to call a specialist right away, there are several simple ways that will allow us to fix the radiator on our own and become the heroes of our home . What to do if the heater does not work?

Let’s start with the simplest thing – checking the drain valve . We often look for serious reasons for a non-working radiator, while in most cases it is enough to gently unscrew the drain valve. An inconspicuous element is located at the bottom of the radiator and is most often covered with a hexagonal masking cover. After unscrewing the drain valve, the radiator should work fine, if there is still something wrong, let’s go to the next step.

A heater failure may be due to a broken thermostatic valve, specifically a pressed needle. To check if the thermostatic valve is broken, set it several times to the minimum and maximum. An efficient heater at maximum temperature should be very hot after several minutes. If it is not, it may be a sign that the needle is stuck. To fix it, just unscrew and remove the thermostatic head. Then we will see a spire, a protruding pin. If it is pressed too much, turning the thermostatic valve does not work and hot water does not get to the radiator. To unlock and pull out the needle, just grasp its end with pliers and pull it towards you. After such treatment, the heater should start working immediately. What if it still is cold ? Then we implement plan B.

sealed central heating system - radiator leaking, gland nut or pinhole leak - to avoid such disasters again, use a rust and corrosion inhibitor and a radiator cleaner regularly
Leaking radiator valve? Easy fix.

If, after checking the drain valve and the thermostat needle, the radiator still does not want to work with us, it’s time to bleed it. The air in the radiator not only does not give off heat – you can often hear gurgling or water overflowing inside. Why does the heater air out? Mainly due to assembly errors and leaks in the installation. Air enters the central heating system, which results in low water pressure and a cold radiator. How to bleed the radiator? It is very simple. First, we turn off the thermostat and wait for the radiator to cool down. If our radiator does not have a thermostat, it is enough to shut off the water supply. When the radiator is cold, put a container or a bowl under the vent valve (usually in the upper part of the radiator) and carefully unscrew it with a wrench or screwdriver. Then we will hear a whistle of air and water will start pouring out. When the air becomes silent, close the valve and turn on the thermostat. The heater should work.