Hot water issue

Maintenance

Help needed figuring out how to fix a hot water issue:

I own a 2-bed flat in an apartment block which has a shared hot water supply (i.e. 30 apartments take their hot water and heating from a central supply) There has been issues with the hot water since the building was completed in 2018 and currently none of the apartments in the building have any hot water supply to them. 

There is currently a stand-off between the freeholders and leasholders as to the costs associated with fixing this. We are seeking legal help, but it's unlikely the hot water will be fixed soon.

I need to figure out how to ensure my tenants have hot water. The plumbing is not set-up to fit a traditional boiler, so wondering if anyone has alternative solutions (e.g camping shower, or portable hot water heater)

Any ideas welcome!