What is Heater: Definition and 201 Discussions

Heating, ventilation, and air conditioning (HVAC) is the technology of indoor and vehicular environmental comfort. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics and heat transfer. "Refrigeration" is sometimes added to the field's abbreviation, as HVAC&R or HVACR or "ventilation" is dropped, as in HACR (as in the designation of HACR-rated circuit breakers).
HVAC is an important part of residential structures such as single family homes, apartment buildings, hotels and senior living facilities, medium to large industrial and office buildings such as skyscrapers and hospitals, vehicles such as cars, trains, airplanes, ships and submarines, and in marine environments, where safe and healthy building conditions are regulated with respect to temperature and humidity, using fresh air from outdoors.
Ventilating or ventilation (the "V" in HVAC) is the process of exchanging or replacing air in any space to provide high indoor air quality which involves temperature control, oxygen replenishment, and removal of moisture, odors, smoke, heat, dust, airborne bacteria, carbon dioxide, and other gases. Ventilation removes unpleasant smells and excessive moisture, introduces outside air, keeps interior building air circulating, and prevents stagnation of the interior air.
Ventilation often refers to the intentional delivery of the outside air to the building indoor environment. It is one of the most important factors for maintaining acceptable indoor air quality in buildings. Methods for ventilating a building are divided into mechanical/forced and natural types.

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  1. TomD1

    H2O2 35% on Al 5083 at 150° gives 'limescale'

    Hi, In our production line we are heating h2o2 in a heater made of Alu 5083 to 150° for the disinfection of plastic bottles. After 6 months we needed to revise and clean our heater due to some sort of "limescale" formation. It only occurs at the beginning of the heater (I guess before...
  2. K

    Heater power keeping a room constantly warm from low temperatures outside

    I've been trying for 45 minutes and doing research but I can't even find a start to how to approach this. :( [Mentor Note: New user reminded to always show their work on schoolwork problems. That work is shown in a subsequent post below]
  3. K

    Induction heater using Bicycle Dynamo Generator @ 24 V 60HZ Supply

    I was wondering about the possibility of Induction heater powered by Bicycle Dynamo (alternator/generator) without using any other circuit element. Which means connecting 24 V 50 to 60 HZ AC to Coil with turns around 100 in pancake shape (10 inch diameter ) and Stainless steel plate of 3 mm...
  4. G

    FUN induction heater circuit

    If you have not built an induction heater yet it is a fun project. Build the small circuit with 6 yellow capacitors first. Induction heater is a fun project. I built a small induction heater then I wanted a more powerful one. A small unit is so simple you can build it in about 2 hours work...
  5. K

    Induction Heater at 50Hz or 60Hz from Kitchen Wall Outlet.

    I'd like to make an Induction Heater design for Cooking purpose, where heat can reach up to 400-500F or so. I read in some other forums, that it's possible. So I'm trying to get more ideas and possibly learn how this can be done safely (in case I make it / if it's really safe). The Idea is use...
  6. M

    Calculating total heat transfer by solar water heater

    I have a solar water heater on my deck, with a circulator powered by PV, that pumps heated glycol through a wand heat exchanger placed in an 80 gallon tank. Water comes from the well's pressure tank, passes through this solar pre-heater tank, then into an LPG heater that adds any heat needed. I...
  7. Kamuna

    Engineering Regenerative Rankine cycle with one contact feedwater heater

    My question is how do i get : A. required steam generated from the boiler per hour B. extracted steam per hour for feedwater heater C. thermal efficiency of the cycle I can solve the thermal efficiency but A and B is giving me difficulties, i know when solving the extraction of steam needs mass...
  8. PaxFinnica96

    Engineering Steam Turbine with Open Regenerative Feed Heater

    I would very much appreciate anyone to cast their eye over my attempt at solving this problem which I've been struggling with the past few days. Many thanks in advance. Assuming that: energy input from open-type regenerative feed heater pump is negligible no energy is lost the heater pressure...
  9. DaveC426913

    Pool heater and flow rate

    I am having a heater installed for my 12ft round above ground puddle pool. The heater is a K-Star K-5 (5kW) heater. The manual says the heater's max flow rate is 8GPM and I'll need to install a diverter with a valve to bypass it until the flow is <8GPM. How do I determine what my current flow...
  10. M

    LiFePO4 battery heater project (makes sure battery doesn't freeze)

    I think PID is overkill (but would consider it). I am thinking of setting up an array of thermistors around the battery to make sure that they are all above T? Maybe two on top, two on the sides. The battery is about 8"x20". I am building an r10 insulation box around the battery, which will...
  11. S

    Water heater pipe attenuation

    There are 2 kinds of home instant bathroom water heater. The multipoint and single point (or shower heater). The latter is one where the unit is connected directly to the shower head. In the multipoint, its located a distant away and it serves multi points like sink and bath. What would happen...
  12. B

    I want a temperature controller for a 12V, 40W ceramic cartridge heater

    Dear friends, I am in a search of a temperature controller for 12V, 40W ceramic cartridge heater! I can not change the heater because of my application. I want to purchase a simple PID temperature controller available in the market. But I am not sure whether they can provide me the 12V output...
  13. Shees

    Mechanism to Automatically Lower Heater for Sealing Packaging

    Hi i need a mechanism to lower the heater to certain height then it will automatically go up. It could be auto or manual hand mechanism. In short i need a mechanism which is installed in drill press table machine to lower drill bit. But in my scenario it is heater to seal small packaging of...
  14. kyphysics

    If My Water Heater Doesn't Work, Is Water Still Safe to Drink (if Cold)?

    My water heater has an issue. I still get cold water, but is that safe to drink if the water heater is not working? Thanks!
  15. J

    Induction Heater Design: Resources & Tips from Jeff

    Hello; I am trying to come up with an induction heater design for a machine that i am working on and am having some trouble planning it out. Anybody have some good resources? I have scoured Google and there are tons on there. I am a bit unsure how to get started. I have an induction heater...
  16. E

    Heater Sizing Calculations

    I am trying to determine the size of a single cartridge heater or 2 cartridge heaters to heat a large mass of aluminum to 400F. The aluminum block will be sitting inside an insulated (all sides) enclosure. The following are the specs for this problem. - Max surface temp of aluminum block is...
  17. Wrichik Basu

    Which type of room heater is better?

    We were thinking about buying a room heater. The minimum required would be 1000W (?), considering room size of about 120sq.ft. The temperature doesn't drop below 10°C normally. We found that there are two types of heaters: coil type and halogen lamp type. We will buy one that has a fan...
  18. J

    Source strangulation for an instant water heater?

    Got an electric water heater in my flat, one of those instant ones. It outputs a low flow but this is alright as you mix the hot water with cold water in the shower. Problem is, in the summer you need to mix in too much cold water in the shower and the heater shuts down, probably as it senses...
  19. J

    Choosing a heater band for vacuum system bakeout

    Hello, I'm trying to find the right wattage heater band for a cylindrical vacuum chamber that is stainless steel (304), ~2ft in length, ~0.5ft in diameter, and ~0.5 in thick. From a quick google search, I was able to calculate the required wattage for bring the chamber up to and constant at...
  20. J

    Determine the required value of feedback (H) to control the heater output

    Just need a bit of guidance to make sure that I am heading the right way. Question is: Fig 3 shows the block diagram of the control of an electric heating system. The heater is driven from a voltage-controlled power supply, the voltage V1 being derived from a potientiometer. The output...
  21. J

    Electrical Solar to Hot Water Heater Hookup

    If one hooks up solar panel to bottom element after removing AC line seemed like good idea then I was wondering if the wires going to the element will get hot instead of the element see drawing.
  22. T

    Pressure in a water heater - does it depend on size?

    Picture two water heaters - one 10 liters and the other 100 liters, initially filled with cold water. If both of them are heated to the same temperature, will a pressure meter display the same pressure for both tanks, or is the resulting pressure somehow dependent on the size of the tank?
  23. J

    Electrical Electric Hot Water Heater 2000 watt 220 volt run on 110 volt

    Will a hot water heater element that is rated 220 volt AC by 2000 watts when only applying 110 volt AC just put out 1000 watt instead?
  24. M

    Calculate number of turns for an electric heater

    Homework Statement Need to calculate, how many turns of nichrome wire do I need on a cylinder to make a heater with resistance of 40 Ω. Wire diameter = 1mm Cylinder radius = 2.5cm R = 40 Ω Wire diameter = 1mm Correct answer - 200 turns Homework Equations R = ρ*l/S R = resistance ρ = specific...
  25. P

    Silicon not heating with induction heater?

    I’m using an inductive heater to try to melt some 99.85% polycrystalline silicon, as would occur in the Czochralski process, but the silicon workpiece is not melting let alone even getting hot. The silicon workpiece is about the size of a playing dice. It becomes conductive at 200 F and becomes...
  26. G

    Converting a household space heater to DC

    Hello, Basically, I use a portable electric space heater to keep my room warm during the winter, and it works quite well, except it makes a very loud hum that keeps me awake, so my options right now are poor sleep due to hum or having my room drop to about 12 C over night if I turn the heater...
  27. D

    Heating efficiency of a Heat Pump and a Space Heater

    Homework Statement Instead of pumping heat into the cabaret air from the outside air, you could simply put an electric space heater inside the cabaret. A space heater turns electrical energy directly into thermal energy. Why would operating a space heater consume more electric power than...
  28. K

    Electronics Temperature Sensing to Switch on/off an Induction Heater

    Hello, I'm having trouble thinking of ways that I can measure the temperature of an object that I am heating using an Induction Heater. A little background: The coil and workpiece will be submerged in liquid, and due to most thermometers being metal it won't work with the induction heater. I'm...
  29. J

    BTU Calculation for a fireplace-based heater

    An online seller claimed with an 80 Cubic Feet per Minute blower his output temperature was 350 degrees Fahrenheit from a fireplace heat scavenger. If you assumed his measurements were correct and the room temperature (input) was 70 degrees F. how would you calculate his gain in British Thermal...
  30. DaveC426913

    Understanding Propane Heater Behavior: Causes and Solutions

    I've asked a related question before, but this is new. I have one of these propane heaters: As months go by, it has an increasing habit of spazzing out. It will frequently do this in a strong gust. But with even a little wind, and more often when it is set on low, it will spontaneously and...
  31. Shadow89

    Optimal values for power in an induction heater?

    I really want to build a simple but powerful induction heater for hobby blacksmithing. Metal shaping and the design of the cooling system within the coils are not a problem. I need help understanding the electronics Obviously I must first use a transformer as a safety against "backlash" to the...
  32. N

    How do I control this heater?

    So I have a coiled (Nichrome) heating element that's rated at 120VAC 60Hz. (Resistance of 14.4Ohms) I am trying to use this heating element to warm up air blowing across it. I will have thermistor on the outlet end to monitor the temperature of the output air. This heater is coiled inside of a...
  33. E

    How long to heat a given volume of air?

    Homework Statement I am working on a problem where I need to determine the time taken for an air heater with an 8kW output to heat a volume of air of 9m^3 by 25C. I am neglecting all losses at the moment. It almost seems too simple in my mind that I'm concerned I'm overlooking...
  34. ecjoyner

    Telescope dew heater band

    I want to make my own scope dew heaters, I have 8 meters of nichrome band, with 1,82 ohm/meter resistance. How do I calculate the length for a specific temperature (around 8 Celsius over ambient) and how to wrap it i.e. in a coil or in a series of parallel 320° circles? The circumference of the...
  35. N

    Blackbody heater and a sensor

    Homework Statement At room temperature, an infrared sensor with an area 0.1mm2 is suspended 0.1m above a disc that is a blackbody heater of diameter 0.05m . The infrared detector absorbs all thermal infrared radiation (0.2 - 100 microns) produced by the blackbody heater. What are the losses...
  36. R

    Adding a 2nd Secondary coil & effects

    Hi, We have an induction heater, like a stove top one, not industrial. I want to understand what happens when an additional load is added that it isn't intended to receive. A plate goes on the induction warmer, it gets heated up, then removed and another plate takes it place. What happens if the...
  37. D

    Does the volume of water affect efficiency of heater?

    Ok, so i did a physics experiment a few days ago and now i have to do a write up. The question is does the volume of water in the calorimeter affect the efficiency of the immersion heater? Could someone pls explain to me what happens & y? My results showed that as you increase the volume, the...
  38. G

    US-Style Water Heater: Tips for Optimal Performance and Safety in the UK

    Hi all, I've just moved to a house in the Highlands whose previous owner was American, and insisted on installing US appliances, presumably shipped over at great expense. I wonder if our US friends on here could help with the water heater: Is it just California state law to write all that...
  39. H

    Water heater - storage or tankless

    Hi all, I'm thinking of buying a new water heater, and still confused to choose between storage water heater vs demand water heater (tankless). Can anybody give me the pros and cons of each? what I have so far: 1. Tankless consumes more power, and the longer you shower, the more it consumes...
  40. J

    Help Interpreting PID Controller Settings

    I am somewhat familiar with a PID controller and how it operates. But I am having a hard time interpretting my PID controller setting and getting them to do what I want. I figured I would open up here for some help. I have a copper cylinder that is being heated up with a band heater. in the...
  41. A

    Tubular cartridge heater wattage

    Hi, I have a machine equipped with 2000mm long tubular cartridge heater (230V, 1600W, 4mm diameter). This tubular heater is sandwiched between the two steel plates (2000mm long) i.e. the heater keeps the steel components hot. My problem is that the temperature of the steel components varies...
  42. M

    Electric Element Voltage Specifications?

    Hello, I have a question about electric elements and their corresponding voltages. I am looking at powering a 1500W 120VAC element out of an ordinary kettle with a DC voltage supplied by solar panels. So, from what I understand, 120VAC represents the RMS voltage meaning that it would require...
  43. D

    Seebeck generator from placing water heater next to freezer

    Water heater is set at 130 degree f freezer is 5 degrees f. Is it possible for a thermoelectric generator to collect energy from these placed side by side? Would the extra energy used by the heater and freezer due to the presence of the generator cancel out and then some any energy that could...
  44. S

    Heating oil from -20 degrees Celcius with an immersion heater

    Hi I am planning on building an immersion heater to heat oil when it is -20 C degrees outside. I need some help calculating the heat transfer. I want to find out how long it would take to heat around 10 litres of oil from -20 degrees to 10 degrees using an immersion heater with a constant...
  45. J

    How to find out Heater gain ?

    Hi I am an electronics and communication engineer and hence doesn't know about heat transfer or termodynamics. I need to design a system using PID where I need to control the temperature of water in a boiler by controlling AC power to boiler heater. I don't have the datasheet of the heater. I...
  46. A

    Induction Heater Coil Design

    I am designing an induction heating rig to heat a strip on the surface of a steel sample with repeated quenching, through holes in the heating surface of the coil (shown in the third image). The rig should heat the sample to around 600C in 20 seconds, and quench to 30C in 20 seconds. Firstly...
  47. duhuhu

    Electronics Issues in Vacuum

    I am working on a project for a cube-sat to go up on a balloon to 40 km. My team has been talking to some other groups who have worked on other cube-sats who say that our resistive heaters need to be Kapton heaters rather than 1D heaters like what we have designed for. They claim that our...
  48. Robertphysics

    Induction heater question

    I know for them for some time and I understand how induction heating works in general , where you have a coil through which a high frequency AC current is fed that creates a magnetic field which changes fast according to the frequency and this excites electrons in the metal introduced and heats...
  49. K

    Effect of voltage on resistance wire life expectancy?

    I am using a 30kW air heater which is using resistance wire. I am not exactly sure what type of wire it is and hope this will not be an issue in answering this question. The heater is rated at 380V and 45amps(max)...my supply is 415VAC (+ 6% and - 10%) and 45amps. Any idea if this extra...
  50. K

    Pressure losses in electric air heater

    I have an electric air heater with a pressure loss of 3kPa (according to manufacturer at the flow rate and temperature I will be using). Air is supplied to the heater using a centrifugal fan with a static pressure of 8.7kPa (gauge) and a flow rate of 88m3/hr, giving a dynamic pressure of around...