What is the difference between electronic pressure pumps and pressure tank units?
Functional principle of electronic pressure pumps:
The main functional elements of our electronic manometric switch are a sensor receiving magnetic signals from a rotating turbine (flow control) and a contact element that is opened or closed by water pressure (pressure control). Therefore, when the pump is switched on, the contact is opened by decreasing water pressure, and the pump is put into operation by the rotating turbine. This happens within split seconds.
When switching off, the stop of the turbine and the simultaneous closing of the contact is reported to the electronic system by the contact element. The pump is deactivated within approx. 20 seconds.
The cut-in pressure is approx. 2.2 bar and is factory-set. As long as water is taken the pump is running permanently thus providing for a constant pressure that depends on the flow rate. When the pump is switched off the maximum pump pressure is achieved that builds up automatically. So, a decreasing maximum pressure due to wear of the pump is automatically considered. The dry-running safety prevents damage of the pump when no liquid flows.
Functional principle of pressure tank units:
1. The pump delivers water into the pipe until the consumer is closed.
2. Then the pump delivers water into the rubber balloon in the steel boiler (initial pressure in the boiler: 1.5 bar).
3. The rubber balloon extends and compresses the air in the steel boiler.
4. After having reached a defined cut-out pressure, the pump switches off.
5. When the consumer is opened, water comes first out of the rubber balloon (=> pressure in the boiler decreases).
6. The rubber balloon empties until a defined cut-in pressure is reached.
7. The pump switches on and delivers water into the pipe.
Features of the GARDENA Electronic Pressure Pumps:
- continuous operation like the water mains as soon as water is taken. Therefore, particularly suitable for watering systems.
- are equipped with a dry-runing safety, therefore specially suitable for use with rain water tanks.
- small, compact design, ideal for mobile use, space-saving storage.
- are equipped with a LCD display showing flow rate, pressure as well as operating mode
Features of the GARDENA Pressure Tank Units:
- Switch on only after approx. 5 - 10 litres of water have been taken (depending on model) and are therefore specially suited for use in the house and garden without the operation of watering systems or when there is non-reparable leaking on the pressure side (e.g. old water mains).
- no flow control, therefore usable also when small quantities of water are taken (e.g. specific types of washing machines, toilets)
- equipped with manometric switch for pressure reading.
Should a pump have more capacity or more pressure, what is better?
The so-called jet pumps have a single turbine and a jet valve.
Features: better suction and more suction height as well as relatively more pressure than capacity. They are used for large distances and large height differences.
The so-called multi-stage pumps have the following features: silent, less suction height, relatively more capacity than pressure. They are used for watering systems and wherever noise should be minimized.
What place should be chosen for installing the GARDENA Garden Pumps, Electronic Pressure Pumps and Pressure Tank Units?
Those pumps must not be exposed to rain. The place must be dry, clean and protected from frost. Sufficient air ventilation is recommended.
How long can garden pumps, submersible pressure pumps and submersible pumps be operated without delivering – that means with the output closed?
No longer than 5 minutes.
Can the GARDENA Pumps be used also if only small amounts of water are taken (small hose cross sections, drip irrigation system, toilet flushing etc.)?
Yes, they can. In general, a small trickle of at least 90 l/h is sufficient to cool and grease the hydraulic parts of the pumps. Exception: The GARDENA LCD Electronic Pressure Pumps need a flow rate of at least 140 l/h.
Are some of the GARDENA Pumps usable with potable water and/or food-safe?
All GARDENA pumps, electronic pressure pumps, hose couplings, hoses, pipes and also all other products are not suitable for use with potable water. Products suitable for use with potable water must have been analyzed and certified accordingly. As GARDENA does not need products suitable for use with potable water for the original business, such certification has never been aimed for (high expenditure of time and cost).
This applies also to food safety. The GARDENA products have not been examined or certified in terms of food safety. Therefore, they cannot be recommended for corresponding use.
Are the GARDENA Garden Pumps, Electronic Pressure Pumps and Pressure Tank Units frost-proof?
No, they aren’t. They must not be exposed to frost even when they have been drained, but have to be placed or stored protected from the cold to prevent damage to the hydraulic unit. Please note that in general summer houses and garages are not 100 % frost-proof.