If your boiler stops working, makes unusual noises, fails to maintain the water temperature, or your consumption increases, it’s usually not “bad luck”: it’s a clear sign that your system is no longer efficient or reliable. At AlquiConfort, we use PRO-G Holanda MIXPLUS condensing boilers because they deliver what a home needs today: consistent comfort, strong performance, and cost control with no surprises.
Below is a straightforward guide (without unnecessary technical jargon) to determine which boiler you need and which PRO-G MIXPLUS model is the best fit for you.
1. First things first: why a condensing boiler?
In existing homes, a condensing boiler is generally the most efficient and convenient option, as it reduces energy consumption compared to older technologies and recovers heat from the combustion gases. In addition, the PRO-G MIXPLUS range features premix condensing technology, designed to deliver high seasonal efficiency (Class A) and comply with ErP requirements.
Outcome for you: greater comfort with lower energy consumption, plus a future-ready technological base that supports modulating controls and outdoor sensors, depending on the installation.
2. The 5 questions that truly define which boiler you need
- How many m² is the home, and how well insulated is it?
Insulation is key: a well-insulated home typically needs less heating power. - How many people live in the home?
The more hot water (DHW) is used (showers, kitchen), the higher the comfort demand. - How many bathrooms, and how many water outlets are used at the same time?
If there are simultaneous showers, choosing the right model becomes critical. - Priority: heating, hot water, or a balance of both?
In Spain, the main “pain point” is often DHW: when someone opens a tap and the shower temperature drops.
Natural gas or LPG, and what is the flue system like?
This affects configuration and feasibility. The MIXPLUS allows the gas type to be selected via settings, but it must always be validated by an installer.
3. Which PRO-G MIXPLUS model you need (quick guide)
AlquiConfort offers 4 PRO-G Holanda MIXPLUS versions, all condensing models designed for different home profiles.
Think of it this way: the more bathrooms you have and the more people using hot water at the same time, the more “powerful” the boiler needs to be so the shower doesn’t lose temperature.
✅ MIXPLUS 24
Best for: apartments and small homes, 1 bathroom, standard usage.
Typical example: 1–2 people, one shower at a time.
✅ MIXPLUS 28
Best for: medium-sized homes, 1 bathroom (or 2 if they’re not used at the same time), families.
Typical example: 3–4 people, with a noticeable boost in hot water comfort.
✅ MIXPLUS 35
Best for: medium to large homes with 2 bathrooms and higher demand.
Typical example: a shower and the kitchen tap running at the same time, or several showers back-to-back.
✅ MIXPLUS 40
Best for: large homes, multiple bathrooms, or high simultaneous usage.
Typical example: two people showering at the same time without the temperature dropping.
4. Renting vs buying: the smart choice for your situation
This is where AlquiConfort changes the game compared to the traditional purchase model.
If you want zero friction and zero surprises: “all-in” rental
The rental model is designed so you pay a fixed monthly fee and don’t have to worry about anything else:
- Full maintenance every 24 months
- Emergency repairs included
- Replacement if it can’t be repaired
- Full coverage for the duration of the contract
If you don’t want an upfront investment, value peace of mind, or prefer a “service-based” model (which is closely aligned with European trends), it’s a perfect fit.
If you prefer to buy, but with coverage: an All-in-Service subscription
MIXPLUS products include options with an All-in-Service subscription (+€14.95/month) to maintain coverage and keep post-installation costs under control.
Frequently Asked Questions
Is a more powerful boiler always better?
No. Oversizing can reduce efficiency and comfort. The key is balancing real heating needs with DHW demand.
Which model should I choose if I have 2 bathrooms?
In many cases, the MIXPLUS 35; if there’s frequent simultaneous usage or a large home, the MIXPLUS 40.
How often is maintenance carried out?
With AlquiConfort’s rental service, full maintenance is included every 24 months, plus emergency interventions and replacement if needed.
Do you have any questions?
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