Electrical engineer with HVAC difficulties,Help plz!!
Electrical engineer with HVAC difficulties,Help plz!!
(OP)
Hi !!
I need some help,I am a fresh electrical engineer & I have been given a drawing for HVAC & I am having some difficulties.
First of all, if I have a compressor written next to it "2 Nb. compressor" & it is feeding two Evaporator mini split,then does it mean I have two air conditions here fed from one compressor?am I interpreting right?
Second of all,I was given BTU/hr but I don't care about that all i care about is electrical watts and not thermal watts so that I can calculate the current but i can't find a way to convert from KWth to KWe or from BTU/HR to KWe all i found was to multiply by 0.2931 which would give me thermal watt.I have 36000,24000,18000,12000,& 9000 BTU/HR & I want their current for a single phase 240V system,how can I get the values? does anyone have a table or website they can recommend???
Thx a lot!!
I need some help,I am a fresh electrical engineer & I have been given a drawing for HVAC & I am having some difficulties.
First of all, if I have a compressor written next to it "2 Nb. compressor" & it is feeding two Evaporator mini split,then does it mean I have two air conditions here fed from one compressor?am I interpreting right?
Second of all,I was given BTU/hr but I don't care about that all i care about is electrical watts and not thermal watts so that I can calculate the current but i can't find a way to convert from KWth to KWe or from BTU/HR to KWe all i found was to multiply by 0.2931 which would give me thermal watt.I have 36000,24000,18000,12000,& 9000 BTU/HR & I want their current for a single phase 240V system,how can I get the values? does anyone have a table or website they can recommend???
Thx a lot!!





RE: Electrical engineer with HVAC difficulties,Help plz!!
I just found out that I can convert the BTU/hr to ton & then use an estimate of 1.5 to 1.7 KVA/ton for a good estimation.
So can somebody simply answer at the first part of my post.
Thank you!
RE: Electrical engineer with HVAC difficulties,Help plz!!
RE: Electrical engineer with HVAC difficulties,Help plz!!
go to their website and download the electrical data. it should give you information of breaker size or amp. load requirement of the equipment.
RE: Electrical engineer with HVAC difficulties,Help plz!!
power consumption for an energy calc is a lot smaller than the load calc needed for electrical drawings
Take the "V" out of HVAC and you are left with a HAC(k) job.
RE: Electrical engineer with HVAC difficulties,Help plz!!
RE: Electrical engineer with HVAC difficulties,Help plz!!
http:
May be of use to you in the future for literature, etc.
RE: Electrical engineer with HVAC difficulties,Help plz!!
OR just divide the BTU/hr value by the EER (energy efficiency ratio) which will give you watts and accounts for the conversion.
This is if you don't have elec. data (better bet always to do what Hepa99 indicated using manufacturer tags).
CB
RE: Electrical engineer with HVAC difficulties,Help plz!!
If there are no ME's on staff, hire a consultant. Trying to fake this will cause trouble.
RE: Electrical engineer with HVAC difficulties,Help plz!!
RE: Electrical engineer with HVAC difficulties,Help plz!!
Relating power consumption to performance is so varied that I would only use that kind of methodology for budgets and planning. For actual design and sizing of electrical, use real data.
RE: Electrical engineer with HVAC difficulties,Help plz!!
Thank you guys a lot,I didn't know this thread was still going,I ended up contacting the mechanical people & they sent me the electrical data,it turned out they just put numbers without backing them with anything,I mean usually I am either given a table with minimum specifications of the system or at least the model, anyway they sent me the electrical data,Nb also turned out to have some meaning don't remember what it was.Also,the 1.7 KVA/ton gave an extremely close estimate.
Anyways,thank you all of you!!!
RE: Electrical engineer with HVAC difficulties,Help plz!!
I think "Nb" stands for number. u already mentioned that you have 2 no. evaporators, so these each will be feeding seperately from the correspong compressors.
Then for converting Btu/h to kW, u can use 1kW=3412 Btu/h.