Bulldog 2.0 provides an innovative yet simple solution for a cost-effective path to electrification and decarbonization for HVAC systems by significantly reducing natural gas consumption or facilitating the adoption of Air Source Heating.

Bulldog 2.0 employs a factory-mounted and pre-wired electric resistance heater, working alongside a low-temperature hydronic heating coil capable of efficiently operating with water temperatures as low as 95°F. The low-temperature requirements of this hydronic loop allow for highly efficient heating using either traditional condensing boilers or air-to-water heat pumps. The electric heater can provide additional electric heat capacity without increasing the unit’s overall MCA or MOP, keeping electrical requirements comparable to those of traditional water-source heat pumps. Furthermore, Bulldog 2.0’s electric heater can be configured as either the first or second stage of heating, tailored precisely to application requirements.

Mechanical cooling remains reliably available all year-round, preserving all the traditional Bulldog advantages, such as quieter operation, lower maintenance requirements, extended compressor life, and superior reliability compared to standard water-source heat pump (WSHP) systems.

In regions where natural has is restricted or carbon reduction mandates apply, Air Source Heat Pumps (ASHPs) are increasingly desirable. However, ASHP systems often become prohibitively expensive when sized for low ambient conditions. Bulldog 2.0 solves this challenge by enabling smaller, more cost-effective ASHP plants, providing substantial flexibility to meet both environmental and economic objectives.

Additionally, Bulldog 2.0 future-proofs HVAC heating systems with an integrated fuel-switching strategy, mitigating risks related to uncertain availability or fluctuating energy costs for natural gas and electricity. Bulldog 2.0 will reduce boiler gas usage or enable smaller, more efficient Air Source Heating plants, optimizing both cost-efficiency and sustainability.

What is Bulldog 2.0?

Bulldog 2.0 is a simple yet versatile fuel-switching solution enabling building managers to choose between two heating sources based on their immediate goals and needs.

 

Available heating sources include:

  • Hydronic heating
  • Electric heating.
  • Combination of both sources simultaneously, if necessary.

Primary energy sources for heating plants:

  • Boilers: Can utilize natural gas, electricity, or other available fuels.
  • Air Source Heating: utilizes electricity.

 

How is heating source selection managed?

  • By scheduling the water temperature set point, the building management system (BMS) directs the appropriate heating source. The Bulldog 2.0 control board activates either electric or hydronic heat based on this set point. Cooler water temperatures trigger electric heating, while warmer water conditions favor hydronic heating.

Can heating sources operate simultaneously?

  • During peak demand periods, if the primary heat source fails to satisfy the thermostat within 10 minutes, the second source automatically engages to meet heating demands.

How does Bulldog 2.0 Compare to a Reversing WSHP?

Unlike reversing WSHP systems, which deliver a fixed heating ratio (approximately 20-25% electric and 75-80% from a central plant), Bulldog 2.0 allows complete flexibility in prioritizing heating sources, offering dynamic control based on real-time requirements.

Location of Bulldog 2.0 electric coil:

  • The electric coil is conveniently unit-mounted at the fan discharge, with a single-point power connection for easy installation and maintenance.

 

 

Reduces natural gas consumption by 50% or more over traditional WSHP.

  • Reduces Air Source Heat Pump (ASHP) size and associated costs by 50% or more.
  • Facilitates easier transition to Air Source Heating.
  • Offers dual heating source capability: electric, hydronic, or both.
  • Future-proofs heating systems with flexible fuel-switching strategies.
  • Allows prioritization of fuel sources based on daily objectives.

  • Transfers more heating costs to tenant meters.

 

 

Choosing the Optimal Fuel Source

Bulldog 2.0 strategically integrates flexibility, efficiency, and sustainability, making it a powerful, forward-thinking solution for modern HVAC heating applications.

 

Bulldog 2.0 projects Montreal, Ontario, NYC, Miami.