pressure switch problem?

Old 10-02-12, 06:36 AM
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 1
Upvotes: 0
Received 0 Upvotes on 0 Posts
pressure switch problem?

I also have the same problem. When shorting accross the pressure swich, the igniter and flame comes on properly. The vacuum to the switch has been tested by a technician, and the switch is labelled at -1.58. With over -1 in. h2o vacuum from the inducer duct, we determined the flue is not blocked, and probably a bad pressure switch. The switch part # is HK06ZB104, which has been replaced by HK06NB124 from Payne. Waiting for the new switch to arrive.
My question is this: if the new pressure switch is adjustable, what should it be adjusted to? Does the -1.58 on the old switch mean the switch closes the contacts at that vacuum, or that is the maximum vacuum to the switch?Why is this called a pressure switch when vacuum energizes it? On one side of the switch, a hose goes to the flame box and gas valve, which I assume is static pressure.
Old 10-02-12, 10:03 AM
SeattlePioneer's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Jul 2007
Location: Seattle, Wa
Posts: 4,469
Upvotes: 0
Received 1 Upvote on 1 Post
Most OEM pressure switches from Carrier are not labeled with the pressure at which they close.

However, assuming what you have is what you say you have...

The pressure4 switch measures the negative pressure in the furnace being developed by the inducer motor. A pressure switch labeled -1.58 should closed when a negative pressure of -1.58 inches water column is applied to it.

You say your measured -1, which means you don't have enough negative pressure to close the switch. That implies that something in the furnace is plugged up (usually).

Also, I would use only Carrier OEM parts in the furnace. Pressure switches are a critical safety feature, and installing and trying to adjust a pressure switch is a formular for present and future problems.

Besides, only about 5% of the time is a bad pressure switch the reason a pressure switch wont close. It is almost always a defect in the venting system of the furnace.

My suggestion is not to tag on to an existing thread, but to start a new one. Tagging on to an old thread rapidly becomes confusing and information on someone else's furnace is rarely of any use.

Start as new thread with the facts you have at hand.
Old 10-02-12, 02:32 PM
hvactechfw's Avatar
Join Date: Jan 2011
Posts: 5,491
Upvotes: 0
Received 4 Upvotes on 4 Posts
New thread started!.......................

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: