Heat pumps have an important role in decarbonising the UK. 

Many houses that currently rely on gas boilers for heating and hot water will be converted to a heat pump over the next decade.  All new build housing will be heated by electricity only from 2025. 

The webinar by Trystan Lea is a case study of how he replaced a gas boiler in a typical mid-terrace house to a heat pump.  The webinar was recorded as part of Eco Open Houses Online.

The webinar is two short films below:

1. Talk where Trystan discusses heat pumps
2. Question and answer session. 

Heat pumps webinar outline:

Part 1 - Introduction of case study:

• How I became interested in heat pumps
• A key technology in ZeroCarbonBritain
• A very brief overview of how heat pumps work
• A non-technical overview of our house and heat pump installation (pictures of the install, radiators, hot water cylinder etc)
• A quick overview of monitored results (Co-efficeint of Performance of 3.9, carbon emissions based on grid intensity, costs etc)

Part 2 - A bit more detail on system design:

• Microgeneration Certification System (MCS) room by room heat loss calculator
• Flow temperatures and Co-efficeint of Performance (COP)
• Overview of radiator sizing
• Overview of hot water cylinder design and options: coil, plate heat exchanger, thermal store
• Legionella protection
• System diagram of our system
• Control approach: single zone, single thermostat (not too complicated), TRV’s open, maximum area, minimum flow temperature (it’s a small house)
• Buffers and low loss headers
• More monitoring data example

Heat pumps webinar Q&A

Some of the questions asked included:

• Could you explain a bit more about the Legionella risk and how this risk may be mitigated?
• Can you recommend an electric fan heater/radiator that works well with a heat pump?
• What is the approx pay-back period on initial cost?
• Can the heat pump become air conditioning in the summer months?
• How noisy is air pump?

Speaker biography:

Trystan Lea has been working on monitoring heat pumps for over 5 years with John Cantor of heatpumps.co.uk and as part of OpenEnergyMonitor. He became interested in the technology after reading about the important role that heat pumps have in zero carbon energy scenarios such as ZeroCarbonBritain. His most recent project involved the design, installation and then monitoring of an air source heat pump on his own mid-terraced stone house in Snowdonia.