How does an Air Pressure Switch work in a Gas Furnace

How does an Air Pressure Switch work in a Gas Furnace - HVAC

Рет қаралды 94,285

North America HVAC

6 жыл бұрын

Explanation of a how air pressure switches operate in gas furnaces and water heaters.

Пікірлер: 30

@Silent-Lucidity 2 жыл бұрын

This video helped me diagnose a bad inducer motor. Couple hundred bucks and 30 min later we have heat! Thanks!!

@jimbarron8688 9 ай бұрын

Did you check the inducer capacitor first? Sometimes they go giving the impression that the vendor motor is bad.

@johnwhitehead8129 6 жыл бұрын

The video was helpful. Easy to understand!! Much appreciated

@julioquintero9936 6 жыл бұрын

Excellent video

@PBS-nm1uu 5 жыл бұрын

great presentation thanks

@jeremyhenderson163 4 жыл бұрын

Thanks for sharing, very informative. Not sure if I'm looking at the right component for my DIY project, I need an in-line component that can measure a gaseous pressure and connect/disconnect a power source based on the parameters of the component?

@keytothegate68 8 ай бұрын

When he said there is no way to tell the pressure inside the pressure switch unless you have this special tool (600 bucks) ... Well they need to update those things to look more 21 st century than mid 20 th. They could have built in digital gauges or a universal port to give you a better understanding of just what your furnace is doing ?

@tonypresley9534 5 жыл бұрын

Thanks

@josephengert2504 6 жыл бұрын

Just an update from Lennox. They don't warranty if you want to be proactive. If you DIY your pressure switch because there is a problem and then phone the company for warranty they will not warranty the switch. So let your house freeze, pipes burst, etc. then phone the company even though you know that there is a problem.

@edwardaddison1331 5 жыл бұрын

Joseph Engert can you short across a furnace pressure switch to check if it is the problem

@canuck-guy2384 Ай бұрын

I have the dual switch as shown in the video. My question is when I checked the switch on the right it showed continuity with the inducer motor running. The one on the left showed no continuity. In the meantime my furnace motherboard is flashing that the limit switch is the issue. I checked it for continuity on the limit switch and it is good. Help!

@stooges1951 6 жыл бұрын

I just made a order today 11-1-2017 for a pressure switch

@nikex2197 Жыл бұрын

I have yet to see a video that explains the function of the 2nd p.switch. It is set higher than the first on on my American Standard (Trane) furnace. I can only assume that the pressure from the inducer motor must run above the lower limit to indicate adequate air flow, and below the upper limit which might indicate a blocked output.

@jimbarron8688 9 ай бұрын

The second pressure switch has a higher setting which closes when the thermostat (or circuit board of furnace) calls for high heat. In this case the ventor motor goes to high speed creating a higher vacuum. This closes the high fire pressure switch. The board then energizes the gas valve to the high fire output, typically 3.5"wc. Finally the board energizes the high heat blower speed to maintain the heat rise across the heat exchanger. Furnace runs on high fire until satisfied.

@calgibs6911 7 ай бұрын

Its because its reading what the inducer motor housing ganna pull more thats not a two stage valve or inducer

@calgibs6911 7 ай бұрын

I tested a -.10"wc on a goodman system yesterday tested the collector box cover was reading -.17"WC but the voltage was fluttering on the switch even thoe it was over manufacturing rating so i have ordered a switch see if thats whats up

@daltonc810 7 ай бұрын

Goodman pressure switches are garbage, replace it with a universal matched to the correct water column

@jackpine4347 9 ай бұрын

One other issue can leave the pressure switch stuck in the open position - debris in the air tube nipple that the tube attaches to on the inducer motor. Our Goodman furnace was blinking an open pressure switch code on the controller board. After determining the correct voltage was reaching the switch and that the air tube was not leaking, we then tested that the switch could close by sucking on the end of the tube and checking for continuity through the switch. As a final test we turned on the furnace power and sucked on the air tube - the diagnostic light on the controller board stayed lit, indicating no other issues we could detect without testing the switch with a manometer. Rather than opting to climb up on the roof to check the chimney next, we took a stiff, thin wire and reamed out the air tube nipple on the induction motor - it felt a little crunchy! We reconnected the air tube, and lo and behold, the light on the board stayed on and the furnace ignited! So, before inspecting the flue for a blockage, clean out the air tube connection on the induction motor.

@danielkilbourn4961 5 ай бұрын

Are both pressure switches the same?

@jasonkeuma1986 3 ай бұрын

They have different ratings. (Normally) Example. One might be -1.05” and the other might be -0.40”.

@johnaries9301 Жыл бұрын

Can you wire an air pressure switch backwards?

@jimbarron8688 9 ай бұрын

It's power in and power out. Doesn't matter.

@user-dd9ni5bg2i 5 жыл бұрын

Жаль на русском языке нету видео. А то у меня проблема с реле разряжения

@rfbedell347 Жыл бұрын

Do NOT buy anything from this Sham of a Business. They offer NO warranties nor any customer service.

@Ramone46 6 жыл бұрын

Hi I have a question. I own and operate my own HVAC company and you have no idea how many service calls we go on and find out that a customer has tried to do the work on there own. My question is why are you selling parts or even pushing a customer to buy their own parts when we all had to go to school and to be certified to be able to work on any equipment ? I'm sorry to say that this path really hurts our industry. John F. Pres. Rams Heating LLC

@MEMPHISBIGC 6 жыл бұрын

Get over it John.. I'm certified. HVAC stores are a rip off, I bought a control board for my Rheem RGDG model. Crooks charge me $237.00.. because I didn't have an account with them. I could have purchased it online for about $125.00. People who are ordering online are certified too !!!!!! Johnstone has best prices on from store purchases , but did not have the Rheem part that I needed.

@johnwhitehead8129 6 жыл бұрын

One question Pres., how does it hurt your industry when a HOME OWNER messes up their property(unit), and then calls a professional to fix it, if they happen to have failed? Isn’t that called job security? I wouldn’t know though, I’m a flunky and have been for years. I’ve been known to sweep the aisles in your local department store, after closing hours of course!! Y’all hiring?

@Ramone46 6 жыл бұрын

Hi. As many know that pressure switch are funny and if they are not the right ones or handle correctly you will be buying another one. It pains me when every year I have to re new my city, State and my insurances for my company in order to purchases equipment, parts at whole sale. It also pains me to have to do a minimum of 40 hours a year of on going training when a person can go on line these days ? There is an old saying see me now or pay me a lot later.. John

@jeffseefeldt8491 5 жыл бұрын

Tough titty! i had this same part weak in my furnace a repairman came and blew into the tube going to it then the furnace worked!!. He still installed a new pressure switch still but he was not sure which one was bad of the two & charged $100 for a $20 part on ebay i learned so i bought a spare to keep handy and a year later my furnace acted up the same way and i changed the other switch myself without a $100 part & $120 labor bill. It pays to watch your repairman closely and learn from them. It is not rocket science to turn 2 screws and plug 2 wires into spade connectors and attach the hose line to swap this part out

@LanceMcCarthy 5 жыл бұрын

Customers pay for your experience and diagnostic skills. 8 times out of 10, the person will buy the wrong PF rating and have to call you anyways.