backup heat for heat pump

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Hi All,

I'm having trouble with the backup heat for heat pumps in heating mode (used
with air-source heat pumps in heating mode). The program allows you to
select a number of options (furnace, HW, etc), but it seems that only
electric resistance works.

Am I missing something?

Thanks,

--
Karen

No Username provide's picture
Joined: 2011-09-30
Reputation: 200

Dear equesters
This is my second trial in equest,I am using the detailed design
wizard to make the energy simulation
of a high rise building.
The main cooling source for the building is a central chilled water
plant feeding also other buildings in the same area.
I almost finished data entering for the building but I am facing few
problems and I hope you can help me solve them the soonest possible
1-how to simulate the central chilled water plant?
2-does equest have any library for ASHRAE 90.1 values to make a
baseline than compare it to the results?
3-how can I simulate the lighting controls,such as lighting fixtures
controlled by motion sensors?
4-how to enter the elevators and escalators loads?
5-how to model the solar loads gain in the reduction of domestic hot
water calculations?
6-how to impose type of heat recovery to the airhandling unit?such as
total enthalpy fly wheel ?
7-why all edits made in the detailed interface mode are not saved in
the DD wizard?what shall I do to keep these changes?
8-can you provide me with a hot line(if existing)for any urgent
question I may encounter regarding equest items?

b.regards
Haissam al Mahmoud
LEED AP

haissam mahmoud's picture
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Joined: 2011-09-30
Reputation: 0

1. You have to create a chiller. To properly model this system you probably need to model the other buildings and loads attached to the central plant. Or maybe allow the chiller plant to auto size so your not running at part load all the time.
2. Im not sure. I always model as is and refer to Ashrea for my ECO models.
3. You will have to make separate lighting schedules in the detailed mode for each area. You will have to guess at the occupancy and usage. If occupancy frequency is know model your lighting schedule after this.
4. In the detailed mode under Miscellaneous loads. Once again a separate schedule may be required, depends on the level of accuracy your looking for.
5. Not sure? Never dealt with this personally. Possibly you could do your calcs in a spreadsheet then tweek your model to reflect your findings! Once again in detailed mode.
6. This is in the detailed mode under the outside air tab on your airhandling unit.
7. Once you leave the Wizard you are finished with it. All work must then be done solely in the detailed edit mode and the model ran from there. If you re-enter the wizard all your detailed work will be lost. The wizard is only an accelerated way to start your model from the ground up to a certain point.
8. I don't believe there is.
Good luck.

Charles Land's picture
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Joined: 2011-09-30
Reputation: 0

Is this a LEED building? If so then several of your answers will be
determined by LEED/ 90.1 App G. All of my answers are based upon a LEED
project.

1,2: "Required Treatment of District Thermal Energy in LEED-NC version
2.2 and LEED for Schools" will provide answers though it does require
more work.
3: No - there is not a one click solution. You must input the specific
90.1 values for your region/model.
4: Table G3.2 in ASHRAE 90.1 allows a 10%-15% reduction in LPD for
spaces that have lighting controls.
5: I enter this as a direct load on the electrical meter. The archives
have more information on how to do this.
6: This must be done in detailed edit mode under the tab labeled outside
air.
7: Once you have switched to detailed edit mode you cannot go back to
wizard mode without losing the changes you made in detailed edit.
8: You've found the best "hotline available".

Seth Spangler, LEED(r) AP

Tiger06's picture
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Joined: 2011-02-14
Reputation: 0