Hi!
My project has a heat pump, Nibe F1345, and no cooling. The heat pump contains refrigerants, more than 225 g (3.4 kg each). So I should account for them in this credit, right? However, Qunit is cooling capacity. Should we use the heating capacity instead then as Qunit? (We are considering the 40 or 60 kW alternatives). And for equipment type, do we just choose “other” and say heat pump?
Thank you!
David Eldridge
Energy Efficiency NinjaGrumman/Butkus Associates
68 thumbs up
November 5, 2018 - 1:14 pm
When I looked up this unit it shows that it is a "heat pump" that only produces heat, so some people would call this a "packaged DX system" while reserving "heat pump" definition for a unit that has capability to switch between heating and cooling - I don't have the form in front of me to verify but I think your system fits well either as heat pump or if there is a water-to-air packaged system / DX option that could also be appropriate - the premise would be similar that with or without the ability to provide cooling the service life of this equipment would be equivalent to that type of small system with a compressor, similar maintenance. The run hours may not be equivalent since it doesn't also run in cooling but I don't think the form differentiates based on load.
Since the unit is designed to provide heat and there is no cooling rating, I believe you should use the heating capacity in that field. It will be a little larger capacity than the same piece of equipment setup to provide cooling by the amount of the compressor heat (which is useful in this case) by about 15% to 20%.
Does the building not have any cooling equipment?
Maria Porter
Sustainability specialistSkanska Sweden
271 thumbs up
November 6, 2018 - 3:27 am
Thank you David!
I am not an HVAC person so I’m a bit confused with the terms. When googling packaged DX it seems that it cools air and not water. Mine heats water for the radiator system. Here are the specs https://www.nibe.se/assets/documents/24642/639495-12.pdf “Värmepump” in Swedish translates to heat pump. Just that the credit talks about cooling…?
The machines you can choose from in the form are: Window AC or heat pump, Split AC or heat pump, Packaged AC or heat pump, Reciprocating compressor, Reciprocating chiller, Centrifugal chiller, Screw chiller, Absorption chiller, Scroll compressor, VRF, Other (specify). And now that I write them I see that Heat pump is indeed included, I don’t think they were in v2009. I’ll have to go back to my mechanical engineer and ask which of these is most appropriate then.
Ok, since I have good margins, my machines receive 3.4 or 4.59 as results in the calculation table in SI units. (Have to be < 13). So if the reviewer wants me to use 15-20 % lower capacity that doesn’t really matter right?
In Sweden homes, and in this case a nursing home, generally don’t have cooling at all, no. Offices however generally do. But after this last summer we had which was the hottest ever, literally hottest since temperature measurements started in the 1756, I will not be surprised if nursing homes will start looking into cooling as well!
David Eldridge
Energy Efficiency NinjaGrumman/Butkus Associates
68 thumbs up
November 6, 2018 - 3:53 pm
Agreed that you should be okay with the reviewer however it gets entered - although after your description here I would say it wouldn't be any of the three "heat pump" options since these are air systems and the best option may be to describe the compressor (scroll?) or use "other".
In climates that would use heating and cooling, we'd often see a similar type of equipment to make hot water from the ground loop, or cooling from the ground loop, and maybe it could be valved to run heating and cooling at the same time and not use the ground, pick any two.
This wouldn't apply to radiators unfortunately. Anyway - these would be scroll or screw chillers most of the time.