How to properly flush the heating system at home with your own hands?

The heat­ing sys­tem of the house is its blood ves­sels, and the heat­ing boil­er is the heart. Like a per­son, a house can­not exist with­out its most impor­tant “organs”. The sit­u­a­tion in the house, the com­fort of its inhab­i­tants and the cli­mate in the rooms depend on the cor­rect oper­a­tion. It is impos­si­ble to neglect the care of the sys­tem that main­tains a com­fort­able air tem­per­a­ture in the liv­ing space. The heat­ing sys­tem is espe­cial­ly impor­tant in a pri­vate house, where the own­ers live per­ma­nent­ly, because in the event of a sys­tem break­down, you can leave the sum­mer cot­tage, which can­not be done in a per­ma­nent place of res­i­dence.



First of all, it is nec­es­sary to find out the fea­tures of turn­ing off var­i­ous heat­ing sys­tems. Experts dis­tin­guish between two types of heat­ing sys­tems, depend­ing on the method of cir­cu­la­tion of the coolant:

  • Forced.
  • Nat­ur­al.

When per­form­ing flush­ing work, the pro­ce­dure for turn­ing off the devices will dif­fer.

CO selection


Such a sys­tem has a num­ber of pos­i­tive qual­i­ties that attract users:

  • It allows the use of pipes with a diam­e­ter of no more than 25 mm, which sig­nif­i­cant­ly saves ener­gy and reduces the con­sump­tion of coolant.
  • In such a sys­tem, cheap­er pipes are used, this is achieved by reduc­ing their diam­e­ters.
  • The design does not imply seri­ous tem­per­a­ture changes, due to this, the ser­vice life of the con­stituent parts of the sys­tem increas­es.
  • In sys­tems with forced cir­cu­la­tion, it is con­ve­nient to reg­u­late the tem­per­a­ture in the whole house or in some parts of it.

But forced cir­cu­la­tion has dis­ad­van­tages: it must be pro­vid­ed with an unin­ter­rupt­ed sup­ply of elec­tric­i­ty, and many users note that the pump is a lit­tle noisy, but they do not con­sid­er this para­me­ter crit­i­cal.

Collector system


Inde­pen­dent (nat­ur­al) cir­cu­la­tion is used for heat­ing cot­tages and sub­ur­ban pri­vate hous­es. The coolant inside this sys­tem cir­cu­lates due to changes in the den­si­ty of the liq­uid when it is heat­ed. The pop­u­lar­i­ty of such instal­la­tions is due to a num­ber of advan­tages of nat­ur­al cir­cu­la­tion:

  • Avail­abil­i­ty.
  • Easy instal­la­tion.
  • The effi­cien­cy of the sys­tem is explained by the absence of addi­tion­al devices: pumps and pow­er sup­plies.

natural circulation

Why do pollution appear?

Each own­er is cer­tain­ly inter­est­ed in the caus­es of pol­lu­tion of the heat­ing sys­tem in his house. There are sev­er­al rea­sons for this unfor­tu­nate inci­dent:

  • The most pop­u­lar is low qual­i­ty water used as a heat car­ri­er. It would seem that it is pos­si­ble to use a high-qual­i­ty liq­uid and for­get about flush­ing pipes for­ev­er, but it is very dif­fi­cult and almost impos­si­ble to obtain a coolant that is suit­able in all respects. Improv­ing the qual­i­ty of the water in the sys­tem will only help flush the heat­ing sys­tem at home a lit­tle less often.


  • Anoth­er unpleas­ant fac­tor is the insuf­fi­cient amount of water cir­cu­lat­ing through pipes and radi­a­tors. Because of this, rust and sed­i­ment from organ­ic sub­stances form on exposed parts inside the sys­tem.

80% of the space in the pipe is clogged

  • Anoth­er rea­son for the appear­ance of pol­lu­tion is the pres­ence in the water of addi­tion­al sub­stances that adverse­ly affect the qual­i­ty of the coolant: iron, potas­si­um, mag­ne­sium. These ele­ments are released dur­ing the heat­ing of the pipes, they are deposit­ed on the walls first in a small amount, and then form a thick coat­ing, which sig­nif­i­cant­ly reduces the effi­cien­cy of all heat­ing in the house.

The set of mea­sures tak­en to elim­i­nate the prob­lem depends on the nature of the pol­lu­tion.

The flow capacity of the pipe is reduced due to blockage.

Contamination diagnostics

The next step in prepar­ing for flush­ing the heat­ing sys­tem will be the diag­no­sis of pos­si­ble con­t­a­m­i­na­tion. Block­ages will be invis­i­ble in the first stages, when the tem­per­a­ture of the radi­a­tor prac­ti­cal­ly does not dif­fer from the norm and it is impos­si­ble to iden­ti­fy prob­lems with­out spe­cial equip­ment. But remov­ing “young” pol­lu­tion is much eas­i­er than wait­ing for the heat­ing to work much worse.

The most impor­tant sign of pol­lu­tion is the uneven heat­ing of radi­a­tors, it is pos­si­ble to find out the pres­ence of con­ges­tion inside the pipes based on this method using a ther­mal cam­era. In case of severe con­t­a­m­i­na­tion, it can be deter­mined by your own feel­ings when you touch the radi­a­tor. This method is unpleas­ant, because the tem­per­a­ture of the bat­ter­ies is far beyond the com­fort of the human body.

In places of pol­lu­tion, the diam­e­ter through which the coolant flows nar­rows, due to this, the pres­sure in the con­t­a­m­i­nat­ed area increas­es, which leads to a break­down of the entire sys­tem. This fea­ture explains the appear­ance of extra­ne­ous noise when the heat­ing is turned on.

Heat dissipation of a heating radiator

Exter­nal signs may indi­cate the pres­ence of sed­i­ment and block­ages in the pipe:

  • Increase in noise lev­el due to the changed pres­sure inside the pipes.
  • The actu­a­tion of the release valve and the air vent is becom­ing more fre­quent.

These meth­ods for deter­min­ing pol­lu­tion begin to be felt by a per­son only after the block­age reach­es a crit­i­cal state. These signs are not accu­rate mes­sen­gers of sys­tem block­age; experts rec­om­mend check­ing with a ther­mal cam­era.

At the stage of iden­ti­fy­ing block­ages and sed­i­ments, the own­ers will not only have to deter­mine the need to flush the appli­ances, but also find out the nature of the plaque on the walls of the appli­ances and choose the most appro­pri­ate flush­ing method.

Accu­mu­la­tion of cal­ci­um and mag­ne­sium can occur inside radi­a­tors. Sig­nif­i­cant oxide deposits may occur. This is asso­ci­at­ed with the rust­ing of some parts.

The most pop­u­lar com­po­si­tion of con­t­a­m­i­nants includes ele­ments com­mon­ly found in water:

  • Cal­ci­um and mag­ne­sium deposits togeth­er make up about 60% of total block­ages.
  • About 25% is occu­pied by pol­lu­tion con­sist­ing of iron oxides. More than oth­ers, steel pipes and heat­ing radi­a­tors suf­fer from this scourge.
  • Cop­per, sul­fur and zinc occu­py all 15%.

Impor­tant! Some­times uneven heat­ing of radi­a­tors does not indi­cate clog­ging, but the pres­ence of excess air in the sys­tem. In this case, it should be released accord­ing to the bat­tery deaer­a­tion instruc­tions.

Heating radiators

Cleaning methods

The next step in clean­ing the heat­ing sys­tem is to choose the most effec­tive option for the work. The pri­ma­ry prob­lem with clogged radi­a­tors is scale on the inside. It is a homo­ge­neous sub­stance on the inside of the pipe. Before pro­ceed­ing direct­ly to flush­ing, scale should be dealt with. To do this, its large parts are bro­ken into small­er pieces and removed from the inter­nal space of a pipe or radi­a­tor using a stream of water.

-Advice- It is impos­si­ble to leave the pump of the forced cir­cu­la­tion sys­tem on when pump­ing out the coolant from the pipes. This may cause it to break.

Even if the heat­ing sys­tem seems to be work­ing, it is still rec­om­mend­ed to flush it every 5 to 6 sea­sons of oper­a­tion.

Cleaning result

Pneumohydraulic shock

This is one of the most time-con­sum­ing meth­ods of clean­ing appli­ances, but it can deal with fair­ly dense dirt. Car­ry­ing out clean­ing work accord­ing to the method of pneu­mat­ic hydraulic shock requires the pres­ence of spe­cial­ized equip­ment in the house. It includes sev­er­al noz­zles and a reli­able hose for pres­sur­ized water sup­ply.

This method has one impor­tant lim­i­ta­tion: it can only be used when clean­ing radi­a­tors with the sim­plest water valve lay­out. The work is car­ried out accord­ing to the scheme for per­form­ing hydrop­neu­mat­ic flush­ing of the heat­ing sys­tem:

  1. First of all, it is nec­es­sary to remove all the old coolant from the heat­ing mains.
  2. In the house, it is nec­es­sary to iden­ti­fy parts of the pipeline that require clean­ing and flush­ing of the heat exchang­er.
  3. The sec­tion of the pipe next to the area infect­ed with scale is dis­man­tled, and the hose with the noz­zle is insert­ed into the pipe.
  4. Water is sup­plied under pres­sure, designed to destroy any con­t­a­m­i­nants.

After the last stage is com­plet­ed, spe­cif­ic flush­ing work ends, and the return of the heat­ing sys­tem to work begins. To do this, it is sim­ply filled with water. The liq­uid must be passed through the pipes sev­er­al times and there­by remove all remain­ing par­ti­cles of the destroyed scale.

This method works well when flush­ing long pipelines or those with sol­id con­t­a­m­i­nat­ed parts.

The water inside the pipes moves in the same direc­tion through­out the entire peri­od of use, so when flush­ing, the flow should be direct­ed in the oppo­site direc­tion. This mea­sure will help remove plaque that has acquired the form of scales dur­ing the use of pipes.

Cleaning with a probe


In sys­tems with a com­plex con­fig­u­ra­tion, it is impos­si­ble to apply water ham­mer. In this case, chem­i­cal clean­ing of bat­ter­ies comes to the res­cue of own­ers of pri­vate hous­es.

The prepa­ra­tions divide the scale into many small parts and crush them into small parts.

The selec­tion of a suit­able flush­ing com­po­si­tion is the most impor­tant step, because with­out it it is impos­si­ble to effi­cient­ly and effec­tive­ly remove scale and at the same time main­tain the per­for­mance of the pipes. There are aggres­sive com­pounds that can destroy alu­minum pipes or poly­mer. Man­u­fac­tur­ers of each clean­ing agent place detailed instruc­tions on the use of the drug on the prod­uct pack­ag­ing and indi­cate all pos­si­ble restric­tions.

The opti­mal, com­pre­hen­sive tool for flush­ing the heat­ing sys­tem will be a spe­cial liq­uid of the SP-OM series. It does not destroy the alu­minum and poly­mer ele­ments of the sys­tem and has proven itself in the indus­tri­al mar­ket. There are var­i­ous brands of SP-OM designed for spe­cif­ic flush­ing con­di­tions and for dif­fer­ent types of heat­ing sys­tems. More details can be found here

Before car­ry­ing out work on flush­ing the heat­ing sys­tem with your own hands, the mas­ter must pre­pare sev­er­al tools:

  • A pump for pump­ing a chem­i­cal solu­tion into pipes.
  • Con­tain­er for liq­uid with chem­i­cals.
  • Wash­ing agent. In most cas­es, it requires dilu­tion with water in the pro­por­tions spec­i­fied by the man­u­fac­tur­er.

After prepar­ing all the tools, you can start wash­ing:

  1. Before start­ing work, it is nec­es­sary to cor­rect­ly con­nect the pre­vi­ous­ly list­ed ele­ments to the cen­tral heat­ing sys­tem of the house using pipes for flush­ing.
  2. First of all, water or oth­er coolant is drained from the heat­ing sys­tem.
  3. The tank of the treat­ment plant must be filled with chem­i­cal clean­ing mix­ture.
  4. After switch­ing on the pump, the entire pipeline is filled with clean­ing liq­uid.
  5. In about 2–3 hours, the scale inside the pipes and radi­a­tors is destroyed, but this time is not enough to destroy the pipes them­selves.
  6. The liq­uid must cir­cu­late in the heat­ing sys­tem for some time. This process occurs before the neg­a­tive deposits from the pipes are deposit­ed in the fil­ter.

Chem­i­cals can harm alu­minum pipes, so after the work is com­plet­ed, the home heat­ing sys­tem is re-flushed. But this time all the work is car­ried out with the use of water.



The main advan­tage of this method is its absolute safe­ty for the envi­ron­ment, bio­log­i­cal prod­ucts can­not harm nature.

Anoth­er advan­tage of bio­log­i­cal treat­ment is the speed of work. The sys­tem does not require shut­down when clean­ing it. This allows the use of bio­log­i­cal prod­ucts even in win­ter at the height of the heat­ing sea­son. Due to this fea­ture, in the event of an unex­pect­ed sys­tem fail­ure, the own­ers of pri­vate hous­es resort to the help of bio­log­i­cal sub­stances.

Cleaning result

Spe­cial prepa­ra­tions are placed in the heat­ing sys­tem, ply­ing through the pipes along with the main coolant. In the process of heat­ing a house, addi­tives can destroy deposits on the walls. Bio­log­i­cal prod­ucts do not harm the sys­tem, they can be used with pipes made of any mate­r­i­al.

Water pulsating mixture

Anoth­er effec­tive clean­ing method is pneu­mat­ic pulse flush­ing. This is a gen­tle method that works well in alu­minum pipes. You will have to per­form work using this method using spe­cial­ized equip­ment and with some expe­ri­ence with it.

The main advan­tage of the method is that it can be used when wash­ing bat­ter­ies with a wide vari­ety of con­fig­u­ra­tions. The essence of the method lies in the short-term sup­ply of increased pres­sure to the sys­tem. The pres­sure val­ue in this case exceeds the work­ing one, and the shock wave speed reach­es 1400 m/s.

Short-term pressure supply to the heating system

Anoth­er advan­tage of the method is the absence of the need to dis­as­sem­ble the heat­ing sys­tem.

Impul­sive clean­ing has sev­er­al impor­tant fac­tors:

  • The diam­e­ter of the pipes should not exceed 10 cm.
  • The method is loy­al to the con­nect­ing ele­ments of the sys­tem, fit­tings, thread­ed and weld­ed con­nec­tions will not suf­fer from a short-term increase in pres­sure.
  • Block­age effi­cien­cy is main­tained even 60m from the point of instal­la­tion of the equip­ment.


When per­form­ing work, the mas­ter must remem­ber that flush­ing and pres­sure test­ing of the heat­ing sys­tem must be car­ried out togeth­er. The flush­ing process is nec­es­sary to restore the health of pipes and radi­a­tors; it has many options for exe­cu­tion using var­i­ous mech­a­nisms and devices.

Pres­sure test­ing of the sys­tem is the process of check­ing its per­for­mance before start­ing the heat­ing and prepar­ing the bat­ter­ies for the load. The main task of the work is to test the tight­ness.

Crimp­ing is car­ried out after each dis­as­sem­bly of the sys­tem for repair, replace­ment of parts or after instal­la­tion.

The pro­ce­dure con­sists of sev­er­al steps:

  • Air or water is sup­plied to the sys­tem using a pneu­mat­ic or hydraulic pump.
  • By mon­i­tor­ing the behav­ior of the sys­tem, leaks can be iden­ti­fied.

When per­form­ing crimp­ing, all faulty or incor­rect­ly mount­ed parts will make them­selves felt, and “healthy” ele­ments will not be affect­ed.

In mod­ern heat­ing sys­tems, a set of works to iden­ti­fy leaky areas can be car­ried out with­out the help of a large num­ber of peo­ple. The mas­ter will need spe­cial equip­ment to car­ry out the work.

Impor­tant! Before car­ry­ing out work, it is impos­si­ble to run coolant into the pipes.

Before start­ing work, it is nec­es­sary to iden­ti­fy the para­me­ters that affect the tech­nol­o­gy of pres­sure test­ing:

  • mate­r­i­al and wall thick­ness.
  • The num­ber of floors in the build­ing.
  • Wiring type.
  • Arma­ture char­ac­ter­is­tics.

Pres­sure test­ing is car­ried out under dif­fer­ent pres­sure, it depends on the mate­r­i­al of the pipes and the oper­at­ing pres­sure. In pri­vate homes, this fig­ure is 2 atmos­pheres. When test­ing for tight­ness, the pres­sure is increased twice rel­a­tive to the work­ing one. The work should be car­ried out by pro­fes­sion­al crimpers, because this is a com­plex process that requires train­ing and cer­ti­fi­ca­tion of the team that per­forms all the work.


Leave a Reply

You May Also Like