Frequently Asked Questions
The system & installation
Understand simply how a reverse osmosis system works, what is installed in your home and what this means for you on a daily basis.
What is an RO system?
An RO system is a water filtration system installed under the sink.
It uses several filters and a reverse osmosis membrane to reduce a large portion of the impurities, undesirable tastes, and residues present in tap water.
The filtered water is then available directly from a dedicated faucet installed next to your main faucet.
Do I need to modify my kitchen to install the osmosis unit?
The installation takes place under the sink and only requires:
- a cold water inlet;
- a drain;
- an electrical outlet;
- a space for the dedicated faucet.
No major work is needed in most compatible kitchens.
What is remineralization?
The Mineros model includes a remineralization step.
After filtration, the water passes through a specific filter that rebalances certain minerals naturally present in the water to achieve a rounder and more pleasant taste for everyday consumption.
What happens to the tap and the hoses if I turn the machine upside down?
If the reverse osmosis unit is returned, the dedicated faucet and installed connections may remain in place.
Only the machine located under the sink must be returned.
What does the first payment include?
The first payment includes:
- €100 (VAT incl.) for installation fees;
- the first month's subscription.
Thereafter, monthly payments will only cover the monthly price of your reverse osmosis system.
Order & payment
Understand what happens at the time of order, why your payment method is requested, and when the first payment may occur.
Why does my order show 0 €?
Because the order is used to register your subscription request and your payment method. No debit will be made today.
Do I pay anything when I order?
No. No payment is made at the time of ordering.
Your payment method is saved to set up the subscription if you choose to continue after the trial.
Why do I have to enter my card details if I'm not paying today?
The card allows you to prepare the subscription and avoid repeating the entire process after the trial.
No payment is made at the time of order. The first payment is only due after the 15-day trial period, which starts on the day of installation.
When will I be charged?
You will only be charged if you continue after the trial period.
The trial begins after installation and lasts 15 days from the validated installation date with the technician.
If you do not request cancellation before the deadline, the subscription automatically starts, and the first payment is debited from the payment method registered during the order.
The amount of the first payment is clearly indicated before validation and includes:
- €100 incl. VAT for installation fees;
- the first month of subscription: €29 incl. VAT / month for Optimos; €35 incl. VAT / month for Mineros.
Subsequent monthly payments then only correspond to the monthly price of your subscription.
What does the first payment include?
The first payment includes:
- €100 (VAT incl.) for installation fees;
- the first month's subscription.
Thereafter, monthly payments will only cover the monthly price of your reverse osmosis system.
15-day trial
Everything you need to know about starting the trial, its actual duration, and what happens if you want to stop before the end.
When does my trial begin?
Your trial only begins after the reverse osmosis system has been installed in your home.
It does not begin at the time of order, nor at the time of machine shipment.
How long is the trial?
The trial lasts 15 days from the date of installation.
What happens if I want to cancel during the trial?
If you wish to cancel during the trial period, simply notify us before the deadline indicated in your trial start email.
The request can be made:
We will then cancel the subscription and send you instructions for returning the machine.
The equipment must be returned within 5 days of your cancellation request.
The date the package is dropped off at La Poste serves as proof.
To simplify the return, a return label can be sent to you to facilitate the shipment of the machine.
Do I pay the setup fee if I cancel during the trial?
No payment is made if:
- you request termination before the end of the trial period;
- and the reverse osmosis system is returned within 5 days of your request.
In this case, neither the installation fees nor the first month's subscription are charged.
Photos & compatibility
Before shipment, we check that your installation is compatible to avoid unpleasant surprises on the day of installation.
Why are you asking for photos?
The photos allow us to verify that your kitchen is compatible with the ordered appliance.
This prevents us from sending you a reverse osmosis system if a technical constraint prevents its installation.
What photos should I send?
To validate the installation, we need a few simple photos:
- a clear photo of the top of the sink and countertop;
- a clear photo of the underside of the sink;
- a photo clearly showing the cold water supply;
- a photo to verify the presence of an electrical outlet under the sink.
Depending on your installation, we may also request additional photos to prepare for the intervention under the best possible conditions.
What happens if my installation isn't compatible?
We will get back to you to examine the situation.
Depending on the case, we may request additional photos, suggest a different configuration, or cancel the request before shipment.
Installation
Steps for organizing the installation of your reverse osmosis system, from photo validation to your home appointment.
Do I need to be present on the day of the installation?
Yes.
The person in whose name the contract is issued must be present on the day of installation, or be represented by a person authorized to sign on their behalf.
This presence allows:
- to grant access to the installation;
- to validate the commissioning of the reverse osmosis unit;
- and to confirm the successful completion of the service with the technician.
Who installs the reverse osmosis system?
Installation is arranged with Oja Water's installation partner.
How is the installation date set?
Once the photos are validated and the machine dispatched, our partner will contact you to schedule an intervention.
Oja Water will then confirm the useful information by email.
What happens if I haven't received the machine before installation?
You must inform Oja Water or the installation partner immediately to reschedule the appointment.
A reminder is scheduled before the appointment to avoid this type of situation.
Subscription
How your Oja Water subscription works: monthly payments, first due date, included services, and cancellation options.
When does my subscription actually start?
Your subscription only starts if you continue after the 15-day trial. The trial begins after installation, then the first payment is scheduled for the end of this period.
What does the subscription include?
The Oja Water subscription includes:
- provision of the osmosis system;
- unlimited daily use;
- replacement filters according to the scheduled frequency;
- Oja Water support via email, phone, or video call;
- assistance with monitoring and using your installation.
If needed, we will first help you diagnose the situation remotely to find the simplest and quickest solution.
If an intervention is necessary, we will organize the next steps with our technical partner.
How much is the subscription?
- Optimos: €29 incl. VAT/month.
- Mineros: €35 incl. VAT/month.
What does the first installment include?
If you continue after the trial, the first payment will include the €100 (VAT included) setup fee and the first month's subscription. Subsequent monthly payments will correspond only to the monthly price of your chosen model.
Can I cancel my subscription?
Yes, you can request to cancel your subscription according to the terms and conditions.
Filters & maintenance
What you need to know about filters, their replacement and planned maintenance to keep your water filtered every day.
Are filters included?
Yes, the sending of filters is included in the subscription according to the scheduled frequency.
How often should I replace the filters?
Filters are replaced according to the scheduled frequency to ensure optimal water quality:
- pre-filter: once a year;
- post-filter (Mineros only): once a year;
- osmotic membrane: every 24 months
- simple replacement in less than 2 min/year;
- Oja anticipates sending to guarantee optimal water quality;
- automatic rinsing to maintain performance.
Replacement filters are included in the subscription.
Do I have to replace the filters myself?
Yes. Filter replacement is designed to be quick and easy, without turning off the water.
We send you clear instructions with the filters, as well as an explanatory video if needed.
Our team is also available to assist you remotely.
Return
Useful information if you wish to stop during the trial or return the machine under the specified conditions.
Should I keep the original box?
Yes, we recommend keeping the original box as long as you use the reverse osmosis system. It will be necessary if you ever decide to return the machine.
How do I return the machine if I cancel?
If you wish to cancel your subscription, please contact Oja Water before the end of your current period.
We will send you the return instructions and a prepaid return label, and you will then have 5 days to return the machine to us.
The date the package is dropped off marks the end of the contract.
Before any return, we can also offer you a buy-back solution for the machine.
What happens if I no longer have the original box?
If you no longer have the original box, you will need to use suitable packaging to properly protect the machine during transport.
If in doubt, contact us before shipping so we can guide you.
What happens if the machine is damaged or not returned?
Until the machine is returned, the subscription remains active.
In the event of damage due to improper packaging, misuse, or an incomplete return, Oja Water reserves the right to charge the residual value of the machine in accordance with the stipulated conditions.
Acquisition
How to become the owner of your reverse osmosis system, understand the calculation of the buy-back price, and what happens next.
Can I buy back my reverse osmosis system?
Yes, you can request to buy back your reverse osmosis system according to the stipulated conditions.
The buyback price depends on the model and the number of months already rented.
How is the buy-back price calculated?
Current base:
- Mineros: €800 incl. VAT - €10 × number of months rented, with a minimum price of €300 incl. VAT.
- Optimos: €500 incl. VAT - €7 × number of months rented, with a minimum price of €200 incl. VAT.
What happens after the takeover?
The subscription ends and you become the owner of your RO system.
You can then order compatible filters as needed.
Customer account
Information available in your customer area and actions you can perform or request from Oja Water.
What can I manage from my customer area?
You can consult information related to your subscription and due dates from your customer area. For any sensitive requests, such as stopping during the trial or rescheduling a due date, please contact the Oja Water team directly by email so that we can verify your situation and make the necessary adjustments.
What is my customer area for?
Your customer area allows you to view information related to your subscription, your due dates, and your payment method.
Can I change my due date myself?
Sensitive requests, such as postponing a trial-related deadline, must go through Oja Water.
This avoids errors regarding installation fees, end of trial, or machine return.
