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What is Central Heating?

Central heating refers to the process of providing warmth or heat to the interior of a home or building from one point to multiple rooms. The heat is created through combustion of fossil fuel either in a furnace or boiler and is transferred usually by forced air ductwork, water circulating in pipes or steam fed through pipes. The heat generation happens in the furnace or mechanical room. Contemporary central heating systems have solar powered sources.

Listed below are a few questions answered by Experts on central heating problems.

What does EPRL mean on a central heating system?

EPRL is a code for a flame sensor fault. The air intakes and the flame sensor rod may have to be cleaned. This can be done in a regular service. Once this is cleaned, there is an 80% chance that your problem will be solved. Another reason for the code could be an electronic issue with the unit’s control card. It would be better to find someone qualified to help with these issues as it is dangerous for a homeowner to attempt repairing them.

What to do if central heating system on the first floor does not turn off even if the thermostat setting is exceeded?

Such a system would usually have two port valves for each zone - upper and lower. The upper zone valve could be stuck in an open position. This could be because of a jammed mechanism on the head or a seized spindle on the body. You could remove the head, which has a cover with two brass screws. You should be able to free the spindle and turn it normally. If you are unable to do this, you should turn off the heating system and call a plumber to check.

What can be done if central heating does not work even after resetting pressure at 1.5 bar?

If the pressure falls or gets too low, air can enter and form bubbles on the top part of the radiators. This could block the water flow. If the water flow is absent, the boiler’s water flow switch will cause the burner to remain off. You will need to bleed the air out of the radiators or any other high points on the system. Ensure that the central heating hot water pump is working fine as well.

Can an air lock cause the boiler in a central heating system to not start after an oil refill?

Though an air lock can cause this issue, it may also be caused because the strainer and nozzle need replacement. This problem can occur when the oil tank level becomes very low. All the residue and waste settles at the bottom of the tank creating a clog. A blow out of the line and replacement is recommended especially when the oil is over.

How to drain the central heating system in a Vaillant Ecotec boiler?

  1. Turn off the system
  2. Connect a hose to the drain valve. This can be found at the lowest position of the heating system.
  3. Open the drain valve and bleed or remove the air from all the valves on the radiator, allowing water to flow out quickly and completely from the heating system and the boiler.
  4. Close the drain valve.
  5. Refill the system with water and release the water from the system till digital pressure of 1.0 bar is achieved. Ideally, the reading on the digital pressure gauge should be 0.5 bar plus an additional pressure corresponding to the highest point on the system from the base of the boiler. In most installations, the minimum pressure should not be less than one bar. If an inhibitor needs to be used, it should be applied at this stage as per the manufacturer’s instructions.

What can be done if the pressure gauge goes above normal if the central heat setting is above 50%?

The expansion tank could be defective. The house where the heating system is installed could be too large making the in-built expansion tank too small. You may need an additional 2-gallon size expansion tank. It will usually cost about $100. It can be easily installed anywhere within the central heat circuit piping with the use of a simple “Tee”.

Central heating systems are imperative to maintain a comfortable environment especially in extreme weather conditions. While major problems with the heating will have to be handled by the professionals, minor troubleshooting such as bleeding, refilling oil and so on can be handled by you with help from Experts. Ask an HVAC Expert today and get any information or help you may need while troubleshooting your central heating problems.

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