First we find out where the smell comes from, because the solution depends on it: sometimes servicing the water heater is enough, other times you need aeration. We test and install water treatment equipment in Riga and the Riga region.
Test: does the cold or the hot water smell
Before you buy anything, compare the cold and the hot water. Open the cold tap and let it run for a couple of minutes, smell the water in a glass, then do the same with the hot.
| What you notice | Likely cause | What to do |
|---|---|---|
| Only the hot water smells | Bacteria in the water heater produce hydrogen sulphide together with the magnesium anode | Heating up and flushing the water heater, replacing the anode |
| Both the cold and the hot water smell | The hydrogen sulphide is in the borehole, spike well or well water itself | Aeration or another treatment solution |
| It smells only after the water has not been used for a long time and fades after a while | Water has been standing in the pipes, the filter or the pressure tank | Flush the system, check a filter that has not been changed for a long time |
| It smells only at one sink | The smell comes from the drain or the trap, not from the water | Check the trap; no water filter is needed |
If the cold water smells too, smell it at the tap by the pressure tank or the sediment filter. If the smell is there, the cause is in the source, not in the house pipes.
Smelly water from the water heater
Water heaters usually have a magnesium anode that protects the tank from corrosion. If the water contains sulphates and bacteria, and the water in the heater stands warm rather than hot for a long time, hydrogen sulphide forms. It often starts after you have been away or when the heater temperature is lowered to save electricity.
- If the water heater's manual allows it, heat it to 70 °C or more and run the hot water through all taps. Take care not to scald yourself.
- If the smell comes back, the magnesium anode can be replaced with an aluminium-zinc alloy anode or an electronic anode. A water heater service or a plumber does this.
- Do not remove the anode altogether: without it the tank rusts faster, and it goes against the water heater's manual.
If only the hot water smells, you usually do not need a water filter, and you do not need to order our service.
Borehole water smells at the cold tap too
If the hydrogen sulphide is in the water itself, it usually comes from a borehole or a spike well (“spice” in Latvian), where the water has little oxygen. In borehole water it often comes together with iron. Then one aeration unit can solve both: air drives out the gas and oxidises the iron, and the filter holds back the deposits.
In a shallow dug well a smell more often means rotting organic matter or silt, and then the well itself has to be put right first: well water smells.
How hydrogen sulphide is removed
| Solution | How it works | When it fits |
|---|---|---|
| Aeration with a filter | Air in the aeration tank drives the gas out of the water and oxidises the iron; the filter holds back the deposits and the gas is vented | Moderate and strong smell, especially together with iron |
| Activated carbon filter | The carbon captures the smell | Weak smell; the carbon must be replaced when the smell returns |
| Oxidation with a reagent and a filter | An oxidant is dosed into the water, then a filter holds back the deposits | Strong smell, if aeration alone is not enough |
Hydrogen sulphide can be measured in a laboratory, but the gas escapes from the sample quickly. So the laboratory usually provides a separate bottle with a preservative, and we take the sample straight from the source before the filters. Sampling and the other parameters: borehole water testing.
How much does removing the hydrogen sulphide smell cost
If the smell is in the water itself, aeration with an iron removal filter costs from €600 including installation, and it often solves the iron at the same time. We connect an activated carbon filter or equipment you have bought for installation labour from €40/h.
The price depends on how strong the smell is, the amount of iron, the water consumption and whether an aeration system with an open tank needs a second pump. More on aeration units: iron removal for a private house. All prices: prices.