no second stage heat
#1
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no second stage heat
I have a york heat pump w/ aux, heat supposed to draw 81a @240v, draws 20.7a when on emergency, can't seem to point out what's causing it. paper work says reverse w1 &w2 for more heat during defrost, same thing as emergency? ambient temp is under 10 degrees f now so shoulg i have to switch it manually ( white rodgers programmable stat ) or install an outdoor stat to lock out compressor when temp gets below say 35 degrees? any input is appreciated.
#2
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More information is required.
Post some pics of the tag on the unit(s) and the heat strips and the low voltage connections at the unit.
You are pulling in one 5 kw strip. How many strips (kw) do you have?
How is it wired?
Is this a package unit?
More information is required.
Post some pics of the tag on the unit(s) and the heat strips and the low voltage connections at the unit.
You are pulling in one 5 kw strip. How many strips (kw) do you have?
How is it wired?
Is this a package unit?
#3
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I know it's 3 strips ( fed w/ 90a ckt. ), heaters are an accessory unit attached to air handler. by the diagram appears 1 stage is 1 strip, 2nd stage is the other 2 along with 1st stage, not sure is series or parralel (sp) , will go underneath house once it warms up a bit (-3 now) & get info. not sure how to load pics from cell to pc but will attempt. thanks!
#4
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On the defrost control board in the outdoor unit, there are jumpers which can be repositioned to address the issues you raise:
1. LOw Temperature cut out (LTCO) - here you can set the temperature below which the heat pump won't run typically set at 10 degrees.
2. Balance point (BP) the temperature above which the defrost control board will not energize the Auxiliary heat when it receives both the W and Y1 signals from the thermostat . W is used for both Emergency heat and Auxiliary heat by the way.
When the thermostat asserts Y1 (for the compressor) and also E (for auxiliary), the control board then asserts W1, which activates, typically, 5kw of Auxilliary heat. Depending on the outside temperature, after a delay (usually 15 minutes) , W2 is activated, then the air handler turns on all heat strips, which sounds like 20 kw for you.
So, the air handler responds to the W1, W2 outputs thus:
W1 alone = 5kw
W2 alone = 10 kw
W1 and W2 = 20 kw.
THe reason for the advice to exchange W1 and W2 is that W1 alone only turns on 5 kw, which is never enough in defrost mode, whereas W2 will bring on 10kw - which is closer to what you need. In their wisdom, York has decided to delay the W2 output for 15 minutes after the W1 output in most circumstances. THis is ridiculous for the defrost cycle since the defrost cycle never lasts longer than eight minutes - hence the swap W1,W2 workaround.
1. LOw Temperature cut out (LTCO) - here you can set the temperature below which the heat pump won't run typically set at 10 degrees.
2. Balance point (BP) the temperature above which the defrost control board will not energize the Auxiliary heat when it receives both the W and Y1 signals from the thermostat . W is used for both Emergency heat and Auxiliary heat by the way.
When the thermostat asserts Y1 (for the compressor) and also E (for auxiliary), the control board then asserts W1, which activates, typically, 5kw of Auxilliary heat. Depending on the outside temperature, after a delay (usually 15 minutes) , W2 is activated, then the air handler turns on all heat strips, which sounds like 20 kw for you.
So, the air handler responds to the W1, W2 outputs thus:
W1 alone = 5kw
W2 alone = 10 kw
W1 and W2 = 20 kw.
THe reason for the advice to exchange W1 and W2 is that W1 alone only turns on 5 kw, which is never enough in defrost mode, whereas W2 will bring on 10kw - which is closer to what you need. In their wisdom, York has decided to delay the W2 output for 15 minutes after the W1 output in most circumstances. THis is ridiculous for the defrost cycle since the defrost cycle never lasts longer than eight minutes - hence the swap W1,W2 workaround.
#8
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jimele:
I did a search on your part number f2rp036h06b which yields:
http://www.upgnet.com/PdfFileRedirec...002-A-0902.PDF
you can probably tell which heat kit you have from the number and ratings of the breakers ...
maybe that'll help some ...
W1 and W2 likely get activated from the outdoor unit control board ... that seems to be the York way.
and probably both w1 and w2 are needed for full auxiliary or em-heat.
Do you know how the system control wiring is connected ... i.e. from thermostat to handler and to outdoor unit, from outdoor to handler .
What is the model number for the outdoor unit ?
I did a search on your part number f2rp036h06b which yields:
http://www.upgnet.com/PdfFileRedirec...002-A-0902.PDF
you can probably tell which heat kit you have from the number and ratings of the breakers ...
maybe that'll help some ...
W1 and W2 likely get activated from the outdoor unit control board ... that seems to be the York way.
and probably both w1 and w2 are needed for full auxiliary or em-heat.
Do you know how the system control wiring is connected ... i.e. from thermostat to handler and to outdoor unit, from outdoor to handler .
What is the model number for the outdoor unit ?
#10
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stat pics

Jerk who wired it used 2-4c cables w/o a markings code so very tough to trace.
sorry for upside down pic , stat is white-rodgers #1f72.
Last edited by jimele; 01-24-13 at 09:27 AM. Reason: add statement
#11
we need a better picture of the thermostat to make out the wiring connections. If you jumper w1 and w2 in the AHU all 3 strips should run with emergency and aux heat and during defrost. I don't recommend leaving it like this, but this may get you some heat for the time being.
#14
Your best option is to get a better thermostat that can handle 3 heat and 1 cool stages (heat pump with aux heat). So, in the mean time or if you decide not to upgrade the thermostat you can put both the w2 and w1 wires in the AHU on w2 or your can jumper them together like I stated in my previous post.
#15
Most thermostats may show the same indoor temp and setpoint and still call for heat because they are actually basing the need for heat on tenths of a degree but only show whole numbers on the screen.
#18
How long did you wait to take the amp draw? Sequencers typically stage the strips on. So you may need to wait at least 2-3 min before taking the reading. If still only 20.7 then yes, something (likely a sequencer) has failed
#20
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Are there one or two white wires connected to the jumpered W2 and E leaving the thermostat ?
A typical York connection is:
jumper W2 (= auxiliary = 2nd stage heat)) with E (emergency);
connect a single wire from the thermostat at W2 / E to a wire to the outdoor control unit - typically just a wire nut connection in the handler where both the cable from the outdoor unit and the cable from the thermostat terminate - not connected to the air handler barrier strip where other wires connect at screw terminals as seen in your photo...
The W2/E signal then goes to the outdoor unit - connecting on a terminal called W, (emergency / auxiliary heat).
Responding to the signal on W, the outdoor unit activates some combination of its terminals W1OUT, W2OUT (usually) depending on temperatures and the state of Y1 (the compressor) . They then appear on terminals W1 and W2 at the handler.
If that's the way your unit works, you should see the (W2/E) white wire from the thermostat directly connected to a wire leading to the outdoor unit ... if not, then I'm wrong in assuming that your unit uses the typical York scheme for controlling the Auxiliary/Emergency heat.
hvactechfw's suggestion to jump W1 and W2 should cause all electric heat to come on whenever auxiliary or emergency heat is activated - if not a failed sequencer is indeed likely - sometimes you can coax a sequencer to work by lightly tapping it which can encourage stuck relay contacts to free up - not a permanent fix of course.
A typical York connection is:
jumper W2 (= auxiliary = 2nd stage heat)) with E (emergency);
connect a single wire from the thermostat at W2 / E to a wire to the outdoor control unit - typically just a wire nut connection in the handler where both the cable from the outdoor unit and the cable from the thermostat terminate - not connected to the air handler barrier strip where other wires connect at screw terminals as seen in your photo...
The W2/E signal then goes to the outdoor unit - connecting on a terminal called W, (emergency / auxiliary heat).
Responding to the signal on W, the outdoor unit activates some combination of its terminals W1OUT, W2OUT (usually) depending on temperatures and the state of Y1 (the compressor) . They then appear on terminals W1 and W2 at the handler.
If that's the way your unit works, you should see the (W2/E) white wire from the thermostat directly connected to a wire leading to the outdoor unit ... if not, then I'm wrong in assuming that your unit uses the typical York scheme for controlling the Auxiliary/Emergency heat.
hvactechfw's suggestion to jump W1 and W2 should cause all electric heat to come on whenever auxiliary or emergency heat is activated - if not a failed sequencer is indeed likely - sometimes you can coax a sequencer to work by lightly tapping it which can encourage stuck relay contacts to free up - not a permanent fix of course.
Last edited by dsomerv; 01-24-13 at 08:31 PM.
#23
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I have 24v at stat not at air handler. I believe it is ok, possibly a relay on control board. No sequencer, done by relays I think, will have to pull board & check relays. Or figure where the 24v comes from - time/defrost board on outside unit?
#24
you have 24V on W2 and or E at the thermostat? How did you test ( just verifying your procedure). Jumper R to G and R to W2 at the AHU and the fan and strips should come on proving it is the stat or wiring.
#25
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Do the 2 white wires from thethermostat connect to W1 and W2 on the control board pictured at W1 and W2 ?
How could it be that the 2 whites are connected at the thermostat but not at their other end - you say 24V on W1 but not on W2.
What wires go to the outside unit ?
If you force 24v on both W1 and W2, all aux heat should come on.
If it doesn't then either the control board is not acting on the W1, W2 signals or it is, and the problen is with the relays the control board actuates or the aux heaters - you need to trace the voltages that appear on the wiring to the heaters .
I assume you've checked that the breakers are indeed on - have you cycled them just to be sure ?
How could it be that the 2 whites are connected at the thermostat but not at their other end - you say 24V on W1 but not on W2.
What wires go to the outside unit ?
If you force 24v on both W1 and W2, all aux heat should come on.
If it doesn't then either the control board is not acting on the W1, W2 signals or it is, and the problen is with the relays the control board actuates or the aux heaters - you need to trace the voltages that appear on the wiring to the heaters .
I assume you've checked that the breakers are indeed on - have you cycled them just to be sure ?
#27
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Since it was wired w/ 2 separate cables, should go to outside unit, yes checked breakers, going to pull main control board & check relays & also continuity test strips.
#28
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you really need to know where each wire from the thermostat goes;
usually the cable routing is from the thermostat to the handler and from the handler to the outdoor unit... maybe yours is wired differently.
Can you make a wiring diagram ... it may be a little work to figure out which wires go where, but in the long run you'll be better off if you know what's connected to what (and why).
usually the cable routing is from the thermostat to the handler and from the handler to the outdoor unit... maybe yours is wired differently.
Can you make a wiring diagram ... it may be a little work to figure out which wires go where, but in the long run you'll be better off if you know what's connected to what (and why).