Sewage pumps for fecal and fecal-free water differ only in the strength of the dirty water. In most cases, the models differ in terms of flow rate and delivery head as well as their performance. In addition, the two model variants have different areas of application due to the different contamination of the water.
We explain the differences between the models and their special features in our sewage pump test 2021. In most cases, the wastewater pumps for water containing faecal matter and water without faecal matter are compared. This should make it easier for you to decide on a model.
- 1 Weekly newsletter with the best personal finance tips
- 2 Summary
- 3 The Best Sewage Pump: Our Choices
- 4 Buying and evaluation criteria for a wastewater pump
- 5 Decision: What types of wastewater pumps are there and which is the right one for me?
- 6 Guide: Frequently asked questions on the subject of wastewater pumps answered in detail
- 6.1 What is a wastewater pump?
- 6.2 What type of wastewater pump do I need?
- 6.3 Why do I need a non-return valve?
- 6.4 What does a wastewater pump cost?
- 6.5 When is a special pump necessary?
- 6.6 What alternatives are there to a wastewater pump?
- 6.7 What maintenance intervals do I have to observe?
- 6.8 Why is my pump not pumping even though it is running?
- 6.9 How do I check my external / internal check valve?
- Sewage pumps make it possible to install drainage objects in detached houses and apartment buildings. In addition, they help to pump out the rain barrel or pool in the garden.
- By using a wastewater pump, it is possible to install a washing machine in the basement despite the lack of a sewer connection. This opens up new possibilities in home design.
- Instead of having the pipe network rebuilt at great expense, a wastewater pump is an inexpensive alternative, at least for minor changes.
The Best Sewage Pump: Our Choices
Buying and evaluation criteria for a wastewater pump
In the following, we will show you various features with which you can decide between the different waste water pumps. The criteria with which you can compare the waste water pumps with each other include:
In the following paragraphs we explain what is important for each attribute.
There are different motor outputs for wastewater lifting units, which are specified in watts. Depending on how many watts a motor is equipped with, the higher the speed of the impeller of the wastewater pump. Accordingly, more wastewater is pumped.
Depending on the place of use (garden, cellar, for example) and the type of project, such as pumping out a cellar that has filled up due to heavy rainfall. The important thing is to get the water out of the cellar as quickly as possible so that the structure of the building is not damaged.
Before the pump is put into operation, the fuse must be checked. The fuse should be able to withstand the water. As the wattage increases, so does the power consumption. Thus, depending on the project or the circumstances, the power connection may well increase from 230 to 400 V.
The delivery head is related to the output. The price of the pump also depends on the output and make. Therefore, you should have measured in advance which delivery head is necessary for the work to be carried out.
It is of great importance that the backflow preventer and the pump are cleared of sludge and debris during maintenance. If this is not done, the head can be greatly affected by reducing the cross-section and/or possible damage to the impeller.
If the impeller or even the backflow preventer becomes jammed due to deposits that have not been removed, the pump will not be able to deliver and, in the worst case, the pump will suffer a defect or the drainage objects/shafts will overflow.
Flow per hour
The flow rate per hour ( l / h) results from the power of the pump (Watt), the speed of the impeller and the connection size of the pump pressure pipe. The greater the wattage, pipe diameter and connection value ( 230V / 400V), the more dirty water can be pumped. It must also be taken into account that a backflow preventer is installed.
The flow rate per hour depends on the power, the speed of the impeller and the pipe size.
If the backflow preventer does not open properly or is blocked/defective, the flow rate can be throttled. Therefore, the backflow preventer must always be cleaned or, if necessary, replaced during every maintenance. With every wastewater pump there is of course a peak value (l / h), which can only be achieved under perfect conditions.
Nowadays, lifting units usually have a hose adapter (pressure-resistant rubber material), which allows a range of sizes in which you can connect the lifting unit. Just remember: the smaller you choose the pipe diameter, the longer the pumping process will take and the water level will sink more slowly in the lifting unit. Of course, it is up to you in which dimension you lay the pump pressure pipe.
The larger the pipe diameter, the lower the risk of blockage.
The larger the dimension, the more expensive the installation up to the transfer point to the sewer. For fecal-free water, you should not choose the smallest possible dimension. An average value is quite sufficient. The situation is different, however, with water containing feces. Lifting stations for water containing feces are equipped with a chopper.
|Diameter size||Type of wastewater pump|
|Medium diameter||wastewater pump for fecal-free water|
|Maximum diameter||wastewater pump for water containing faecal matter|
This shreds toilet paper and excreta, but it would make sense to choose the maximum diameter so that no blockages can occur. In addition, when flushing 6-9 litres (toilet flushing), it is advantageous to pump the water out quickly so that it does not rise in the sanitary objects.
In the case of lifting units for feces, the maximum size of the pipe diameter should be selected, as it happens time and again that objects are thrown in there. (e.g. tampons, sanitary towels, hair elastics, non-recycled toilet paper)
Residual water level
Lifting stations will always have residual water heights, as these are set by the factory. The pump, which is located in the lifting unit, can never completely clear the housing of water. The pump would otherwise draw in air and thus run hot.
The pump uses the water to cool itself and to protect built-in parts. Residual water levels vary from manufacturer to manufacturer. Each manufacturer has the same pump design, but components are dimensioned differently during manufacture, resulting in different residual water heights.
However, care should be taken to ensure that the backflow preventer is installed as close as possible to the pump. If the pipe route from the lifting unit to the backflow preventer is too long, the water flowing back can trigger the pumping process again and again.
This means that the pump runs unproductively because it is no longer pumping water. The pump therefore has no function. When buying a lifting unit, it is best to ensure that the residual water level is as low as possible.
The residual water in the pump contains deposits such as residues of textiles (washing machine), soap (washbasins, washing hands), hair and much more. These deposits build up and solidify.
The residual water silts up in the truest sense of the word. These deposits can lead to the basket or impeller of the pump becoming clogged and thus broken. The deposits must be removed during maintenance and thus lead to more frequent maintenance.
Decision: What types of wastewater pumps are there and which is the right one for me?
If you want to buy a wastewater pump, there are these two alternatives to choose from:
|Sewage pump for water containing faecal matter||sewage containing faecal matter that is not connected to the household mains may only be removed with a sewage pump for water containing faecal matter|
|Sewage pump for water containing no faecal matter||water containing no faecal matter that is not connected to the household mains may only be removed with a sewage pump for water containing no faecal matter|
In the following, we will show you the specific advantages and disadvantages of the types of wastewater pumps.
Dirty water pump for water containing faecal matter
The sewage pump for water containing faecal matter has a connection for a toilet and is also the only pump that is allowed to transport water containing fecal matter. This right makes it possible to install a toilet in almost any place in the house and thus to be able to drain it.
The disadvantage is that it is very expensive to buy and rather complicated to install. It is subject to more wear and tear and therefore requires more maintenance than its counterpart. In addition, the use of recycled toilet paper is prohibited.
Sewage pump for faecal-free water
The wastewater pump for water without faeces is used in most cases for the garden, pool or rain barrel. It does not have a connection for a toilet, as this pump is not allowed to transport water containing faeces.
This has the night-time disadvantage that you have no design freedom in the living space. Small parts inside the pump that do not belong there can cause the impeller to tilt inside.
Compared to the sewage pump for water containing feces, the pump is cheap to buy and easy to install. The pump tends to have little wear and therefore requires little maintenance.
Guide: Frequently asked questions on the subject of wastewater pumps answered in detail
In the following, we explain the most important questions on the topic of wastewater pumps in our guide. We have selected the questions for you and will answer them shortly. After reading the guide, you will know all the essential background information about wastewater pumps.
What is a wastewater pump?
In the garden, pond or pool area, a wastewater pump for fecal-free water gives you the opportunity to pump out your water. For example, you can pump your pool water into a rainwater pipe and feed it into the sewage system.
What type of wastewater pump do I need?
In the case of clear or slightly polluted water, you need a dirty water pump for water without faeces. If you want to connect your pump to a toilet, this indicates that you need a pump for faecal water.
Why do I need a non-return valve?
It can happen that the water from the sewer line is forced back into the house. The non-return valve prevents water from escaping from the sewage pump and thus avoids damage to the property.
What does a wastewater pump cost?
|Dirty water pump for the pool||from 25€|
|Dirty water pump for the garden||from 37€|
|Dirty water pump for the washing machine||from 80€|
|Dirty water pump for the washbasin||from 80€|
|Dirty water pump for the toilet||from 90€|
Dirty water pumps for the washbasin or washing machine are in the same price range and start at 80€. The cheapest wastewater pump for water containing faeces starts at 90€ and is intended for connection to the toilet. Basically, the prices for the various models can rise into the hundreds.
When is a special pump necessary?
Due to the processing of higher-quality material, the special pumps are considerably more expensive.
These attack, for example, the impeller of the wastewater pump. In a special pump, the impeller is made of stainless steel and is therefore resistant. However, you should check carefully whether you need a special pump.
What alternatives are there to a wastewater pump?
|Collection tank||dirty water is collected, must be pumped out by a company|
|Chemical toilet||tank must be emptied independently|
|Bucket||the pool / pond must be emptied by skimming off the water independently|
Chemical toilets are still used in garden arbours, but in most cases waste water pumps are used.
What maintenance intervals do I have to observe?
From the experience of other customers, it can be stated that a shorter maintenance interval makes sense in order to avoid consequential damage. However, this is at your discretion and depends on the actual use of your pump.
Why is my pump not pumping even though it is running?
It is also possible that an installation part inside the wastewater pump has broken off and the impeller no longer turns. Another possibility is that the non-return valve does not open. This can be the result of the non-return valve not having been maintained or the pump not having been in use for a long time, which has caused it to become stuck.
How do I check my external / internal check valve?
The manufacturers must install the internal non-return valve to ensure the function and correct installation of the wastewater pump. However, you can easily remove the internal non-return valve with a flick of the wrist.
An external non-return valve has a test opening. You can loosen this with an open-ended spanner or a screwdriver and check the function. After checking, you must close the test opening again.
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