Boiler Operation

Boiler Operation

These units are semi-automatic. They will feed automatically though you do need to ‘drive’ them, keep a general eye on them and riddle the grate when required. Due to the massive range of moisture contents there are various tricks to use. If you are running quite dry fuel <20%, leave the grate to ash up a bit. This restricts the airflow in the burn chamber and calms the burn. When running fuel 45>% or arb chip with leaf matter this will need a bit more of a riddle and poke, reducing the ash build up and increasing airflow. Think of these as the happy medium between batch and woodchip boilers. The simplicity of a batch boiler with feed automation of a chip boiler. All with the ability of accepting a far broad mix of fuel and at a higher 55% maximum moisture content. That said, these are not fit and forget units. You get out of them what you put in. A simple 20 minute sweep each week keeps it operating lovely. Ignore it for weeks and it will reduce the stoves draw and affect the performance.

We use conveyor systems to feed rather than traditional auger type as these boilers don’t mind the contaminants like occasional stick slithers/lumps, rocks etc that would normally block up the standard picky wood chip models you normally find. The boiler units are fed from a feed stock bin with scrapers at the base to take the bottom layer of fuel to the lift conveyor which drops it in the boilers fuel chute. The timings of the feed bin and conveyor operations to suit the fuel type is set on the computer.

There are two temperature sensors to monitor the water and stack temperatures. Your hydraulic three way return valve is controlled from the water temperature. The boilers main damper adjusts from the water and stack temperatures. Once either of the water/stack temperatures reach the start modulation point, the control box starts to shut down the air damper on the front chamber door. This reduces the air supply, calms the fire and maintains both temperature and a clean burn. A photoelectric beam sensor monitors and maintains the feed stock in the fuel chute, activating the conveyor and feed bin when required.

The electronics are designed and made in the UK for the U.K. market. It is a self-contained unit with just the sensors and push pull cable for the air damper connecting to the boiler unit.

Maintenance

Easy maintenance, ash removal for the front and rear ash collectors and full sweep of the flue and boiler tubes can be completed in around 20 to 30 minutes. This must be done weekly in general and will help maintain the natural draw and hence the burn of the unit. 

Inbuilt safety

If the water temperature raises to over 95 degrees C for any reason the feed conveyor will halt until temp reduces, so fully protecting the unit. 
In the event of a power cut, no fuel will be added to the fuel chute. The fuel within the burner will take approximately 20 minutes to burn through then extinguish preventing any dangerous heat build up. General fire safety is better due to the high moisture content fuel that these units prefer to run, resulting in less risk of any fire outside of the firebox (also less risk of respiratory issues). To protect the burn chamber case we have a high temperature switch to turn off the unit.An E-stop is mounted on the control panel and feed bin for added safety.