Combi boilers need constant water pressure. To help stay calm under (low) pressure, below are some of the most common reasons & fixes:
- Leak in the pressure relief valve
Debris may have got lodged inside. Valve has to be replaced or cleaned.
- The expansion vessel is faulty
If there’s an issue in the expansion vessel, it won’t be able to handle the expanding hot water. Users will need an expert to do a pressure check.
- Air in the combi boiler system
Find the radiator bleed valve and slowly turn the valve counterclockwise until water starts dripping out. This will release trapped air and let hot water into the cold fins. If bleeding the radiators doesn’t work, contact a technician. Users may have a bigger issue such as an airlock in the system.
- Leak in central heating system
Look for signs of leakage such as a stain on the ceiling, a damp floor, leaky pipes, or a small hole in a radiator. A leak may be located in corroded pipes and radiators.
Types of boilers
A combi boiler is a combination of a water heater and a central heating boiler in one compact unit
There are 3 types of boilers: regular, system, and combi. While regular and system boilers need a cylinder to store hot water, combi boilers heat water from the mains.
A combi boiler is a combination of a water heater and a central heating boiler in one compact unit. For it to work as efficiently as possible, water pressure needs to be stable.
How does a combi boiler work?
A combi boiler heats cold water that flows around a circuit of pipes and radiators through the home and produces hot water when turning a tap on, or when it detects the household is below the preset temperature. It responds automatically by sending hot water to the required tap or firing up the central heating, which means that hot water is available 24/7.
Combi boilers are preferred in the majority of new boiler installations in Canada because of their high energy efficiency, convenience, and compact size. The best combi boiler, such as Navien, will deliver plenty of hot water for showers, baths, and sinks, and will keep radiators piping hot throughout the coldest of winters.