Hello all,

I am trying to model a VRF system which has indoor units hooked up to WSHPs as the outdoor units. I am modelling the system as a WSHP with custom curves and am using hourly reports to zero out the simultaneous heating and cooling. I am running into two problems which are causing very high energy consumption:

1) The fans in the PVVT systems created to model each terminal unit are running 8760 hours, whereas I would like them to come on only in response to heating/cooling demand. I have tried setting INDOOR-FAN-MODE = INTERMITTENT with no response. Is it necessary to change a schedule? and if so which one and how?

2) There is very high electrical end-use attributed to space heating. The EIR for heating on these units is 0.18, but the annual electrical energy devoted to heating is 2/3 of the annual gas energy attributed to heating at the boiler which suggests a very poor COP. Any ideas on why this might be happening?

With thanks and best wishes,
Dan

?
Daniel Knapp, PhD, LEED? AP O+M