Overview

St John the Baptist Church in Owlerton asked Kloska Heating Services to tender for their heating system replacement in August 2023. The church serves as a hub for weekend mass and weekly community groups, so they needed a system that would provide consistent comfort and improved energy efficiency.

Objectives

• Design and install a new heating system capable of maintaining desired temperatures throughout the large church space
• Create separate heating zones to enable efficient heating of specific areas when needed
• Replace the aging 80kW boiler with a more reliable and efficient solution
• Improve the heating capacity while working within the space constraints of the basement plant room
  

Issues

The existing heating system presented multiple challenges that needed to be addressed. The single 80kW boiler, over 20 years old, was frequently breaking down with spare parts becoming increasingly scarce and expensive. The combination of radiators and gas heaters was insufficient to heat the main church area effectively, and the limited wall space restricted options for additional heat emitters. Furthermore, the system’s single-zone design meant the entire church needed heating even when only the back areas (office, kitchen, WC) were in use.

Planning and approach

After thorough assessment, we designed a two-zone heating solution: a 100kW two-boiler cascade system for the main church area and a separate domestic boiler for the back of church. This approach would provide targeted heating control while maximising efficiency. Given our experience with similar church projects, we carefully planned the implementation to minimise disruption to church activities.

Implementation

The project began with splitting the system into two distinct zones. We installed a 100kW Viessmann Vitodens 200 cascade system for the main church area, connecting it through a plate heat exchanger to protect the new boilers from any existing system debris. The number of radiators was increased to 25, utilising all available wall and pillar space to achieve the design goal of raising internal temperature by 24°C against an external temperature of -3°C. For the back of church area, we installed a Viessmann Vitodens 100-W 25kW combination boiler serving nine new radiators and providing hot water for the kitchen and WCs. Both systems were equipped with EPH CP4I internet controllers and Viessmann’s weather compensation features for optimal efficiency.

Results

The new system demonstrated immediate effectiveness, raising the church’s internal temperature from 2.5°C to 21°C within 36 hours, even with external temperatures at 1°C. The zoned heating approach now allows for efficient, targeted heating of specific areas as needed, while the internet-enabled controls provide convenient access for all church staff. The project was completed in December 2024, delivering a clean, efficient, and user-friendly heating solution that meets all the church’s requirements.