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In addition here are my two cents:

1. Always use the system recommended by the manufacturer of your VRV. eQuest can't model VRV properly, so manufacturers choose a given eQuest system and create custom curves for THIS system in order to approximate what's going on. That's why they give you a modeling guide and eQuest curves, so use that. It will also help you justify your approach if you're part of a code compliance or incentive program.

2. As far as heating going up with heat pump compared to elec, it's likely a modeling mistake and/or lack of analysis of the model's output (unmet hours in particular, maybe outdoor air as well). @Daniel's suggestions are on point and also where I would start to debug.

1. Always use the system recommended by the manufacturer of your VRV. VRV. eQuest can't model VRV properly, so manufacturers choose a given eQuest system and create custom curves for THIS system in order to approximate what's going on. That's why they give you a modeling guide and eQuest curves, so use that. It will also help you justify your approach if you're part of a code doing this for compliance or an incentive program.

2. As far as heating going up with heat pump compared to elec, it's likely a modeling mistake and/or lack of analysis of the model's output (unmet hours in particular, maybe outdoor air as well). @Daniel's suggestions are on point and also where I would start to debug.

1. Always use the system recommended by the manufacturer of your VRV. eQuest can't model VRV properly, so manufacturers choose a given eQuest system and create custom curves for THIS system in order to approximate what's going on. That's why they give you a modeling guide and eQuest curves, so use that. It will also help you justify your approach if you're doing this for compliance or an incentive program.

2. As far as heating going up with heat pump compared to elec, it's likely a modeling mistake and/or lack of analysis of the model's output (unmet hours in particular, maybe outdoor air as well). @Daniel's suggestions are on point and also where I would start to debug.

"VRV Heating EIR-F-EWB/ODB AC" = CURVE-FIT      
    TYPE             = BI-QUADRATIC-T
    INPUT-TYPE       = COEFFICIENTS
    COEFFICIENTS     = ( -1.85025, 0.0620141, -0.000312822, 0.07145853,
        -0.0003626328, -0.0007776424 )
    ..

1. Always use the system recommended by the manufacturer of your VRV. eQuest can't model VRV properly, so manufacturers choose a given eQuest system and create custom curves for THIS system in order to approximate what's going on. That's why they give you a modeling guide and eQuest curves, so use that. It will also help you justify your approach if you're doing this for compliance or an incentive program.

2. As far as heating going up with heat pump compared to elec, it's likely a modeling mistake and/or lack of analysis of the model's output (unmet hours in particular, maybe outdoor air as well). @Daniel's suggestions are on point and also where I would start to debug.

@crdugin @crduggin just refreshed my memory. As of July 2014, there was still a mistake in Daikin's curves: eQuest has a limit of 80 characters per line... If you put more it gets truncated.

I emailed some rep twice about it, I don't know if it was corrected or not.

Here's a message I wrote in July 2014 to the eQuest user mailing list:

I've been trying to model a Daikin VRV system and trying to figure out why I was getting 100 times more space heating in the proposed (VRV) model compared to the baseline model (PTHP). After isolating the problem to the VRV, I found a conversation from March 2014 between a few folks (Byron Burns and Bill Bishop mostly - thank you both!), that basically explained why I was getting the issue: the .inp data from Daikin isn't importing correctly.

I just wanted to say that we're in July now, and this still hasn't been fixed (I downloaded the curve from Daikin a few days ago), so if you're having the problem, the fix proposed by Byron and Bill still works. It consists in to replacing the VRV Heating Curve with:

"VRV Heating EIR-F-EWB/ODB AC" = CURVE-FIT      
    TYPE             = BI-QUADRATIC-T
    INPUT-TYPE       = COEFFICIENTS
    COEFFICIENTS     = ( -1.85025, 0.0620141, -0.000312822, 0.07145853,
        -0.0003626328, -0.0007776424 )
    ..

1. Always use the system recommended by the manufacturer of your VRV. eQuest can't model VRV properly, so manufacturers choose a given eQuest system and create custom curves for THIS system in order to approximate what's going on. That's why they give you a modeling guide and eQuest curves, so use that. It will also help you justify your approach if you're doing this for compliance or an incentive program.

2. As far as heating going up with heat pump compared to elec, it's likely a modeling mistake and/or lack of analysis of the model's output (unmet hours in particular, maybe outdoor air as well). @Daniel's suggestions are on point and also where I would start to debug.

@crduggin just refreshed my memory. As of July 2014, there was still a mistake in Daikin's curves: eQuest has a limit of 80 characters per line... If you put more it gets truncated.

I emailed some rep twice about it, I don't know if it was corrected or not.

Here's a message message I wrote in July 2014 to the eQuest user mailing list:

I've been trying to model a Daikin VRV system and trying to figure out why I was getting 100 times more space heating in the proposed (VRV) model compared to the baseline model (PTHP). After isolating the problem to the VRV, I found a conversation from March 2014 between a few folks (Byron Burns and Bill Bishop mostly - thank you both!), that basically explained why I was getting the issue: the .inp data from Daikin isn't importing correctly.

I just wanted to say that we're in July now, and this still hasn't been fixed (I downloaded the curve from Daikin a few days ago), so if you're having the problem, the fix proposed by Byron and Bill still works. It consists in to replacing the VRV Heating Curve with:

"VRV Heating EIR-F-EWB/ODB AC" = CURVE-FIT      
    TYPE             = BI-QUADRATIC-T
    INPUT-TYPE       = COEFFICIENTS
    COEFFICIENTS     = ( -1.85025, 0.0620141, -0.000312822, 0.07145853,
        -0.0003626328, -0.0007776424 )
    ..