retrofitting thermal store with biomass and solar thermal with ASHP

[RodW]

Hi,

 

I work on ventilation systems and thermal modelling for PH buildings and I've stayed in touch with one of my clients from 2011.  He specified the heating system that uses a large thermal store, Akvaterm 1000l, supplied with heat by a biomass stove and solar thermal.  The DHW and space heating are supplied from the TS.  Space healing is via UFH on GF and duct heaters in the MVHR supply air to the FF. There is a PV system on the roof but this is not linked to an immersion in the TS.  The original heating contractor is no longer involved.

 

As he has become older the level of physical work required to operate the stove every day through the winter is too high.  He wants to retain the ability to use the biomass stove for special occasions/resiliency but adapt the heating system to include an ASHP.  He has been contacting ASHP installers but none of them are interested in integrating with the existing TS.  We know this will not be the best way to run an ASHP but the space heating demand of the building is very low. 

 

All the ASHP installers I know design for compliance with RHI so this is too left field for them.  I thought I would ask here to see if retrofitting is a viable option or whether there is a better approach.

 

TIA

 

Rod