[TRNSYS-users] Inconsistency using type 751 and type 60

["Julien L'Hoest" <julien.lhoest@gmail.com>]

Dear all,
I found an inconsistency using type 751 (boiler) with type 60 (storage tank). In my project, the boiler is used the heat the storage tank that supplies a domestic hot water system. The problem is that the energy given  to the fluid by the boiler(output 3) is different from energy given by the fluid to the tank (energy inpupt from heat exchanger 1). Both should be equal since it's a simple loop. There is a pump in the system but the energy transfered to the fluid is negligible. 

The integrated results over a year are as follow: 
energy given to the fluid : 6094 kWh
energy input from heat exchanger 1 : 7611 kWh

I thought it was a problem of Cp of water but it doesn't seem to be that,  does anybody have an idea about this problem ?

Regards,

Julien L'Hoest.