Recent content by hvacers

Goober dave, ACtually i already took the exam but unfortunately i failed the exam. referring to reference list most of the articles are about standards and i noticed during the examination that the questions are actually problem solvings. how did you get prepared for the examinations? Would...

Ideally i would place the DPT at the farthest unit in order to get the real picture at the end of the loop. and you can do testing from time to time and try to reduce the speed of the VFD as long as you dont go below your minimum delta P at the farthest unit

has anybody here took this certification? is it really necessary? and what are the topics coverage for the examination?

hmm.. i dont know about triming down the impeller because if you trim it down the flow will definitely be lowered permanently unlike if you use VFD it can react to the actual change of load. where that is the main concern that i want to happen, i want my pumps only supplying the exact flow...

till how low can i reduce the speeds of my condenser water pumps? is there a limit that the pump cannot be set as low as 30hz. we are 60 hz here in our country. the application of the pump is because i really have a low delta T with my heat exchanger, the pump flow is 2000gpm and i am planning...

i have 5-units of 35kw motor its high rise elevator. assume that its efficiency is 85% and its use factor is 95%. what formular for heat dissipation can i use?

SPU = split packaged unit TR= TONs of refrigeration please advice on the tr/sq.ft

does anybody know the rule of thumb for elevators rooms in designing its SPU. what is its TR/sq.ft thanks guys

Can anybody give me an idea about Energy Utilization Index of different types of buildings and applications. And how to compute it! thanks in advance

the building i am handling is a ceiling return setup. i want to know what is the ruling when it comes to making return diffusers. please help me

what if the the return method is ceiling return?? how to size the main bell mouth return and how many room return diffuser rule should i follow?

Can any body give me ideas how to design return ductings. For example i have 50 TR AHU supplying 20000 CFM to an area? does my return must also be the same as my supply. for example it is just an office space

i reviewed the PH diagram of the system and noticed that the discharge superheat is quite high. My assumption: Since the discharge superheat is high it gives the compressor a hard time and it needs to exert extra power to reach the superheat temp. By needing extra power it triggered the high...

some says its the difference of the evap and condensser temperature...???

what does HIGH COMPRESSOR LIFT mean? I get alot of different explanations from different people and it is starting to become confusing. please share insights