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Storage heater alternative.... Infrared vs lpg vs Air source heat pump
in LPG, heating oil, solid & other fuels
83 replies 3.2K views
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In my last house I had an unvented hot water cylinder that went uninspected for 18 years until I started to get water coming out the overflow. I got it fixed and no harm was done, AFAIK. At that time I was unaware of any requirement for servicing if there was one. I got the gas boiler I had then serviced every two years, as required by the manufacturer. The service engineer who did that never suggested that it might be prudent to give the cylinder a quick once over.
Ah, a warranty requirement, not a legal one.
Had me worried for a while there as I've never had my pressurised system checked, never mind annually. I'm not really sure what there is to check anyway - it's pretty obvious if the system loses pressure.
It will take into account all the enrgy that the system consumes which would include stuff like the defrost cycle, pumps and even the crankcase heater if you've got one. Depending on how its configured and where the power supply is measured it may even take into account any consumption by the immersion or back up heater which could aslo have an effect on the COP.
Heat meters (and I guess the internal heatpump measurement system) measure the incoming water temperature, the out going water temperature and the flow volume through the heat pump and integrate them over time to caluclate the heat output of the heatpump.