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ballvalve
20-12-2013, 07:44 PM
I have a Lennox kha 70 with aMerit® Series Thermostat 51M32
the unit runs ok in cooling but the 4way valve does not denergized
on heating.
any suggestions
cheers

marc5180
20-12-2013, 08:41 PM
Faulty PCB

ballvalve
20-12-2013, 09:27 PM
The wiring on the remote is r,b,c,g,o,y1,w1
and the outdoor has r,c,w1,y1,g,oc,w2,y2
R and c 24volts
y1 cooling
g-fan
w1 is heating but I think it's for electric heaters
not sure which one is for the 4way valve on heating
cheers

marc5180
20-12-2013, 09:34 PM
The wiring on the remote is r,b,c,g,o,y1,w1
and the outdoor has r,c,w1,y1,g,oc,w2,y2
R and c 24volts
y1 cooling
g-fan
w1 is heating but I think it's for electric heaters
not sure which one is for the 4way valve on heating
cheers


Are you sure the model number isn't a KVHK,
O is normally heat/cool selection I.e 4way reversing valve

ballvalve
20-12-2013, 09:41 PM
No it's a Lennox kha 70

marc5180
20-12-2013, 10:12 PM
R 24v from transformer
C common
Y1 & Y2 cooling stages 1 & 2
G fan motor
W1 W2 is electric heater if fitted but sometimes O can also be for the 2nd stage electric heater.

I can't find a copy of the wiring diagram so can't see where the 4 way valve is wired into.
Can you not trace it back from the 4 way valve and see which terminal it comes from on the board?

Also from the model number I would say it is a heat pump but......are you sure

install monkey
20-12-2013, 10:40 PM
http://www.lennoxcommercial.com/technical-documents/service-manuals.asp
cant upload service manual- but its at the bottom of the list

install monkey
20-12-2013, 10:52 PM
http://www.mediafire.com/view/prijxcdyq93d9as/0803a.pdf
service manual- damn mediafire had logged me out:mad:

ballvalve
21-12-2013, 01:49 PM
Here is the outdoor package unit terminals .just not sure if oc is for the heating ie 4way valve

bigor_2
21-12-2013, 06:25 PM
Based on document 0803a.pdf heat pump mode begins when energizes W1. See page 43. You can set a bridge between W1 and R for test WP mode.

joe-ice
21-12-2013, 07:40 PM
Just looking through that manual ,reversing valve is circuit is broken when relay k8 is energised , so it must be wired through nc circuit on relay k8 ,if contacts on k8 are welded or 24 volt coil is shot reversing valve wouldnt de energise.Apologies if you already ruled this out

marc5180
21-12-2013, 08:01 PM
Also check defrost board

bigor_2
21-12-2013, 08:46 PM
Thermostat 51M32 is suitable for non-heat pump units. See source
http://www.lennox.com/pdfs/manuals/Lennox_Merit_Non-Programmable_Thermostats_Manual.pdf (http://www.lennox.com/pdfs/manuals/Lennox_Merit_Non-Programmable_Thermostats_Manual.pdf)

ballvalve
22-12-2013, 09:30 PM
I was looking at the manual for the 51m32. And o is for reverse valve on heating.i was talking to a Lennox engineer and he told me to wire o on the remote to w1 on the package unit but this still didn't work.ill have a better look at unit after Christmas .just left the 4aay valve pluged off the board to let the client have heating over the holidays.