ESBE load valves and load units for biomass boilers
A load valve is a 3-way thermostatic valve that keeps the return temperature to a solid fuel boiler high while it loads the accumulation tank. Here Q-Tech brings together the ESBE load valves and load unit for firewood, pellet or wood chip boilers, in stock in Málaga.
All three models can be delivered assembled and tested in the Q-Tech pre-assembled plant room, ready to connect to the boiler and the tank.
Models in this collection
| Model | Maximum boiler output | Opening temperature | Connection | Pump included |
|---|---|---|---|---|
| ESBE VTC300 load valve | 30 kW | 45, 55 or 60 °C | Rp ¾ or G 1 | No |
| ESBE VTC500 load valve | 150 kW | 50, 55 or 60 °C | Rp 1 or Rp 1¼ | No |
| ESBE LTC300 load unit | 50 to 90 kW depending on the opening temperature | 55, 60, 65 or 70 °C | G 1 or G 1¼ | Yes, 6 m |
Data according to ESBE.
How to choose the load valve
- Boiler output: up to 30 kW, the VTC300; up to 150 kW, the VTC500; 50 to 90 kW with the pump included, the LTC300.
- Return temperature: the one your boiler manufacturer requires. The opening temperature is fixed and is changed by replacing the thermostat.
- Pump: if the system already has a load pump, a VTC; if you want the valve and the pump in one unit, the LTC300.
Applications
- Firewood or pellet boilers with a buffer tank in homes.
- Wood chip or multi-fuel boilers up to 150 kW in warehouses, farms or buildings.
- Replacing an old load valve in an existing boiler room.
Why rely on Q-Tech for your biomass plant room?
- We fit the valve or the load unit in the pre-assembled plant room, tested in our workshop before it reaches your site.
- With a technical call we choose the model with your boiler data, and an on-site Expert Technician installs or checks it on your site.
- All three models are in stock in Málaga, and we answer you on WhatsApp.
Frequently asked questions
What is a load valve for?
It stops water from returning cold to the boiler. According to ESBE, a high return temperature gives higher efficiency, less tar and condensation and a longer boiler life.
Can the opening temperature be changed?
Yes, by replacing the thermostat: ESBE VTC931 in the VTC300 and ESBE VTC951 in the VTC500 and the LTC300. Ask us on WhatsApp.
Do you sell biomass boilers?
No. This collection brings together the loading and return protection equipment for the boiler you already have or are going to install.
What is the delivery time?
They are in stock in Málaga and we dispatch them as soon as we confirm your order.
Choose the model by your boiler output and protect it from cold return water with ESBE and Q-Tech.
Updated 05-11-2026 · v5.4