Replacing an Oil Boiler with a Tatano Biomass Boiler: The Complete Guide

Why replace now

An oil boiler has a typical service life of 20-25 years. Beyond that, efficiency declines (losing 1-2 points per year past the 15-year mark), the risk of leaks increases, and spare parts become scarce or prohibitively expensive. In Luxembourg, installing a new oil boiler has been banned since 2022 — so if yours fails beyond repair, you will be forced into an emergency switch to another energy source. A planned replacement remains 2-3× cheaper than a panic call-out in the middle of winter.

The best window is between April and September: installers are available, Klimabonus grants are fully budgeted, equipment choice is widest, and commissioning can be tested in mild weather.

Step 1 — Thermal audit of the home

Before any quote, an assessment of the property is required. Tatano sends a technician on site or works with you by email/phone: heated floor area, insulation (LU energy passport or BE PEB certificate), number of radiators, type of heat emitters (cast-iron/steel radiators, underfloor heating, fan coil units), current domestic hot water production, and the space available for the pellet silo or wood storage area.

This step produces the sizing of the new boiler, the choice between pellets (recommended as a direct oil replacement) or logs/wood chips depending on your profile, and an estimate of the grants available.

Step 2 — Preparing the project

Once the quote is signed, several items need to be organised in parallel:

• Ordering the Tatano boiler: standard delivery lead time of 3-6 weeks depending on model and options
• Preparing the boiler room: clear 2 to 4 m² for the boiler + 4 to 12 m² for the pellet silo (or wood storage area)
• Checking the flue: diameter compatibility (usually fine for models ≤30 kW), relining if necessary
• Dealing with the oil tank: contact a certified professional for removal or in-situ neutralisation
• Booking the installation: allow 3-5 days blocked out in the schedule

Step 3 — Day 1: removing the old installation

On the morning of the job, the Tatano team arrives with the new boiler, the silo, the hydraulic equipment and the grant documentation. First phase: removal of the old oil boiler. The circuit is drained, then the burner, pipework and the boiler itself are dismantled. Everything is sent for recycling (steel, copper, electronics).

The oil tank is NOT removed by Tatano. If it is buried, a specialist contractor works in parallel or at a later date to degas it (draining + cleaning + filling with an inert material such as sand or foam) or remove it entirely. If the tank is in a basement, it is either physically removed or neutralised. Keep ALL supporting documents (quote + invoice + degassing certificate + before/after photos).

Step 4 — Days 2-3: Tatano installation

The new boiler is positioned in its final location. Hydraulic connection to the existing circuit (heating flow, return, DHW if production is integrated). Connection to the flue with a diameter adapter. Installation of the pellet silo (prefabricated or masonry) or fitting-out of the wood storage area. Connection of the auger feed between silo and boiler.

Electrical wiring: 230 V supply, sensor cables (temperature, pressure, fuel level), room thermostat or outdoor sensor for advanced control. Installation of the 500-1,500 L buffer tank (depending on sizing) in parallel.

Step 5 — Days 4-5: commissioning and training

First filling of the silo (bulk pellet delivery by blower truck, or manual loading for bag hoppers). Filling the circuit with water. Pressure-tightness test. First firing with combustion checks (flue gas analyser: O₂, CO, CO₂, temperature). Modulation settings and timer programming adjusted to your daily routine.

User training: boiler interface, programming, common alarms, emptying the ash pan, refuelling. Handover of the user manual, the manufacturer certificates and the commissioning certificate. Tatano remains available for any questions throughout the first year.

Step 6 — Applying for grants

Once the work is complete and the invoice paid, the grant application is submitted (you file it yourself; Tatano provides the manufacturer documents). In Luxembourg via MyGuichet.lu: the Klimabonus Wunnen form with the invoice, the manufacturer certificate, proof of oil-system removal (= proof of replacement → €8,000), and the title deed. Administrative processing takes 2-6 months; payment is made directly to your bank account. The official deadline for submission is 4 years from 31 December of the invoice year.

In Wallonia: the housing grant is applied for on wallonie.be (a prior home energy audit is mandatory — to be done BEFORE the work). In France: MaPrimeRénov' via maprimerenov.gouv.fr. Keep all supporting documents for at least 10 years (property resale, inspections).

Total cost and savings

For a 150 m² home in the BeLuxFr region replacing a 25 kW oil boiler with a modulating 4-30 kW Tatano pellet boiler:

• Tatano boiler + buffer tank + silo + installation: €12,000-16,000 incl. VAT
• Removal of the buried oil tank: €1,200-2,500 depending on access
• TOTAL project: €13,000-18,500 incl. VAT
• Klimabonus with replacement (LU): -€8,000
• Net cost after grant: €5,000-10,500 incl. VAT
• Fuel savings: ~€1,800/year vs heating oil (3,000 L/year)
• Typical ROI: 4-6 years depending on fuel prices and grants obtained