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Bryant 340MAV048100 series J Pilot won't stay lit

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03-29-14, 08:04 PM

broombli

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Bryant 340MAV048100 series J Pilot won't stay lit

I have a Bryant 340MAV048100 Series J Gas Furnace. I had a HVAC man come look at our unit because the pilot flame was going out; he ran his tests and said it was the pressure switch.
To save a lot of $ I ordered the pressure switch myself and installed it, but the same thing is happening with the new one:when the hose from the switch is connected to the pilot, the flame goes off. It turns back on when it is not connected. I thought I got a bad one, so I sent it back and that one wouldn't work either.
We had another HVAC man come from a different company and he, again, said it was the pressure switch. I decided to get the switch from a completely different supplier - that one also does not work.
So at this point I am doubting it is just the pressure switch, what else could it be???
any help, tips?
Thanks!!!

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03-29-14, 08:13 PM

PJmax

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Welcome to the forums.

The pressure switches are easy to check and very rarely go bad. It's pretty surprising for a tech to come and just change the switch without checking the pressure to the switch.

It sounds like the correct pressure is not getting to the switch. That's what needs to be checked.

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03-30-14, 06:38 AM

broombli

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Both technicians checked the pressure and everything was good.
Also, the original pressure switch has been discontinued HK06NB123, replaced with HK06NB124 - could they be different?

Last edited by broombli; 03-30-14 at 07:33 AM.

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03-30-14, 01:47 PM

PJmax

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Quote:

Both technicians checked the pressure and everything was good.

I don't know what to tell you. If the pressure from the draft inducer was correct the pressure switch would turn on as it's supposed to.

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