How To Test Your Pressure Switch

Today we go over how you can test your pressure switch and possibly what else could be causing the problem.

[@JerichoStephen]

1 question please if it is possible 🌹🙏 Q ? furnace work fine , tech come in for yearly service , after 40 minutes he works on it & I ask him what did you please ? he responded checking gas pressure .After he left our furnace does not work like before , we use to set the thermostat at 75 at night time ,our house was warm but nomore .Now if we set it at 75 , our house has to go to 72 degree so the heat kickes in , now we have to set it at 76 or 77 degree so the furnace works only 10 minutes then we have to go to raise the heat to 78 . My wife has checked thermostat twice , nothing wrong , the whole furnace is only 2.5 years old . When we call what you have done to our furnance they hung up the phone on me or saying it is our emagination . . Now our furnace only work from 76 or up . We are in Va is : we nomore thrust them although we have paid full amount for about 7 years warrenty) I thank you for respons 🙏if you can .

[@kuljinderkalsi2418]

Do you have any video how to replace the inducer motor for the Furnace in the video above ? Thanks.

[@texture6]

Very nice and very informative

[@PBS-nm1uu]

where did you get the jumper i like it,

[@teevee6162]

Thank you saved me a call to my landlord.

[@fernandofhernandez899]

can you go over condensing furnaces multi pressure switches, it s a bit difficult to jump em one at a time, do they close contacts instantly? or you have time to start em quickly one a time??? thanks for the video

[@opentopublichvacschool]

Condensing furnaces are a bit of a pain! So when you have multiple pressure switches (I'm guessing you have a dual pressure switch in a 2-stage system) they do not make contact to close the circuit at the same pressures. You'll have a 2 speed inducer motor that pulls them closed based off of the speed it uses. You will need to jump only the low pressure switch AFTER the inducer motor comes on. It stays in low stage 5-10 minutes depending on the unit.

[@fernandofhernandez899]

@@opentopublichvacschool thank you, yes they are a pain, so i would need to locate the lower pressure switch and that would be the one to jump between 5 to 10 seconds of the inducer startd up, thank you, keep those videos rolling the way you explain the sequence is very simple. thanks

[@chrystalsherrod852]

@@fernandofhernandez899 correct. Your low pressure switch will be the negative pressure that takes less pressure to open. For example, one would be maybe a -.35 and the other maybe, say, a -.75 since the -.35 takes less pressure, that will be the low pressure to bypass.

[@PR-ou9oo]

Very nicely Explained EXCELLENT! keep it 🖕

[@greggardner6883]

Getting a reading :Ao45_Flo pressn Switch Open, Inducer on high speed. What could this mean???

[@j.finesseflights1403]

My unit is a 80% and once it fires and bower proves, the gas valve goes into full-auto like a rifle and burners are backfiring, bang bang, bang bang bang with the valve clicking? WTF...

[@bigdaddy4975]

Also if your meter goes to 0 when the inducer on that is a 100 percent check of a good pressure switch unless see that voltage come back and forth it’s a intermittent problem

[@opentopublichvacschool]

I remember learning about the voltage drop as well. Tracking down intermittent issues can be frustrating for many homeowners when we're walking them through testing.

[@bigdaddy4975]

Your not supposed to put your meter on olms when the power is on that will ruin your meter.

[@opentopublichvacschool]

I didn't think about that, thanks for mentioning it! I appreciate the feedback.

[@jimbarron8688]

You must remove at least one wire from the component you're checking thereby isolating it from the circuit. This also ensures that power is not applied during an ohms check.