Heating issues: why the batteries are cold

Recommendation points

• Low coolant temperature
• Air congestion
• Flushing the heating system
• Battery flushing
• Riser flushing
• Cleaning the system from debris
• The reasons for the weak water pressure at the entrance to the battery
• Battery installation
• The heating system is not balanced

Start your search for the cause of cold radiators by visiting your neighbors and asking them about the temperature of the batteries. If their batteries are cold – the problem is in the common house system, if they are hot – the reason must be looked for in your apartment. Let’s talk about this in more detail in our article..

Low coolant temperature

The reason for cold batteries may be the interference of neighbors in the heating system of the house. The most common violation in this area is an increase in the number of batteries or its sections, a change in the diameter of the distribution pipelines, and new connection schemes. All this leads to overcooling of the water leaving the apartment and an imbalance in the operation of the heating system. The coolant can no longer heat the next apartment to the desired temperature.

If the temperature of the batteries is 30-40 degrees and the movement of water is heard in the radiator, then the boiler room may not be able to cope with the load. It is necessary to call the heat generating company and clarify the situation.

Air congestion

Air locks often form in the system at the beginning of the heating season after quickly filling the pipes with water. On modern batteries (or on risers), special valves are installed that react to air in the system and release it outside automatically. Air vents are often located in apartments on the upper floors. If the devices are not automatic, contact the neighbors on the top floor and ask them to remove the airlock.

Bleeding air manually is very simple – just turn off the valve and wait until water flows. An air lock can often form in your battery. In this case, bleed air from it..

To bleed the air using the Mayevsky tap, turn the valve locking screw, and when water pours out, screw the screw back.

It is more difficult to restore the system to work if there are no air release valves. In this case, unscrew the cap on the radiator until air hiss appears. Screw the plug when water flows out of the gap.

Flushing the heating system

In pipelines and radiators, processes constantly occur that worsen the operation of equipment: the formation of scale and sludge, metal corrosion. As a result, scale and rust build up on the inner walls, and dirt appears in the pipes. A 1 mm scale layer absorbs the amount of heat comparable to thermal insulation of pipelines with mineral wool.

Deposits reduce the throughput of pipes, reducing the supply of hot water to heat exchangers, lead to the appearance of holes in the pipes and reduce the life of the heating system as a whole.

Regular flushing of pipes and radiators ensures the normal operation of the heating system. Washing is done if the thickness of the scale is more than 0.5 mm. It is recommended to carry out the work before the start of the heating season..

Battery flushing

The need to clean the radiator appears if the top of the battery is warm and the bottom is cold.

The battery is removed, disassembled into sections and the dirt is washed off. The scale is removed chemically. After drying, the radiator is assembled, the joints are sealed.

Heavy batteries can be washed on site. To do this, you need a descaling solvent such as soda ash. The plug is removed from the battery, the lower inlet is muffled. Hot water with a solvent is poured inside. After 2 hours, the solution is drained, clean water is poured inside under pressure.

In an emergency, flushing the batteries in the apartment can be done as follows:

1. Shut off the coolant supply to the battery.
2. Drain the battery.
3. Remove the radiator.
4. Take the battery to the bathroom.
5. Remove the side plugs.
6. Rinse the inside of the battery with a hose.

For crystalline formations, prepare a concentrated vinegar solution (70%). Install the bottom plugs on the radiator and pour the solution inside. After 2 hours, rinse the battery with pressurized water. After flushing, install the plugs using tow.

If the descaling fails, the battery is replaced.

Important! The cleaning method also depends on the battery material. For example, aluminum radiators cannot be washed with alkaline and acidic solutions..

Riser flushing

Flushing one radiator will be of little use; after a short period of time, dirt will again fall into the battery. It is necessary to clean the entire system of the house or entrance. To flush the pipes, you will need professional equipment that allows you to clean the system with a water hammer, compressed air, a shock wave even during the heating season..

Cleaning the system from debris

In the heating system, deposits along with corrosion products fall into the lower part of the distribution system and clog it, reducing the flow of water to the heat exchangers. Garbage accumulates at tees, squeegees, outlets. To remove debris, it is necessary to dismantle these elements, remove dirt. The elevator nozzle may also become clogged if the heating system is centralized..

The reasons for the weak water pressure at the entrance to the battery

The main reasons for the low pressure of the coolant:

1. Incorrectly welded polypropylene pipes.
2. Use of taps with a narrowed flow area.
3. Use of small diameter pipes.

In these cases, the coolant pressure is not enough to warm up the entire battery. System elements must be replaced.

In this case, it is necessary to restore the heating system to the design parameters..

In some cases, it is impossible to eliminate the problem without redoing the entire heating system. For example, if the batteries on the upper floors are hot but the lower ones are not.

Battery installation

After repair or installation work, the batteries may heat up partially, for example, only the upper part or the first 2-3 sections. Cause – incorrect connection of the radiator.

In most cases, the battery connection to the network is diagonal – water enters the radiator from above and exits from the bottom. The normal state of the device is when the temperature of the upper and lower parts differs little. A large difference in the heating of the upper and lower parts may indicate an incorrect connection of the hot water pipe. If water is supplied from the bottom and exits through the upper branch pipe, only the first couple of sections or only its upper part will be heated on the battery.

The lack of hot water in the heat exchanger may be due to the installation by neighbors of batteries with built-in thermostats that are capable of shutting off hot water. The operation of such batteries assumes the presence of a bypass pipe (bypass) in the system through which water flows when the thermostat on the radiator is triggered. In the absence of a jumper, the coolant will not flow beyond the radiator.

The heating system is not balanced

With a small amount of water in the system, not all radiators heat up equally. The problem is solved by hydraulic balancing, which will ensure the passage of different amounts of fluid through each device. Adjustment can be performed if the system has bypass and balancing valves, as well as pressure flow regulators.

If the top of the radiator is hot and the bottom is cold, modular balancing is applied. To do this, the network is divided into separate elements (one battery, a group of batteries, a riser, etc.) and equipped with a balancing valve. This device allows you to customize each module.

When carrying out repairs, remember that the water in the system is hot and under high pressure. If you are not confident in your own abilities, call a locksmith from the service organization.