Air Conditioning - condensor or wiring or furnace or thermostat?

Hello All,

Neither my A/C (nor heat) will turn on. My initial thought was to try replacing the thermostat since I had a new digital one laying around but it made no difference. However, installing that just made me more confused (and I dropped the old one and broke it so I can't swap it back in).

Here's what I found:

A/C appeared to be dead; heat/a-c/fan would not turn on so I looked in the furnace and found a blown 5amp fuse. I replaced that and now the fan switches on but the compressor is dead and there's no cool air circulating.

I went to the compressor and can manually turn it on and make the blades spin by pressing a button on the unit itself.

I see a number of wiring diagrams on my thermostat manual but I have no idea which to follow and whether wires should be capped off.

At the furnace I have the following:

R = red wire
Y = yellow wire
G = green wire
W2 + W1 = white wire connecting to both
o = orange wire
c = blue wire

At the thermostat (LUX 1500) - I have the following

G = I connected the green wire
Y = I connected the yellow
W = I connected the white
RH + RC = jumpered, and I connected the red wire
B = I connected the blue wire
O = I connected the orange wire

I have an electric heat/A-C unit with the furnace in the attic and the compressor outside but I have no idea about 4 or 5 wire or single stage etc. The furnace manual says "single piece air handler"

I do have a multimeter but I have no idea how to use it properly

What would be the next thing you recommend when troubleshooting?

I was hoping the blown 5amp fuse was the cause but I think thats a symptom now

What units do you have there???? On some that B is commonand on some that B is for heat valve??????

Not sure of the make, but the furnace says:

UL
F2RP024N06B

and the condensor says;

EBBA F024SE

The new thermostat is a LUX 1500

I've also found that switching the thermostat (in it's current wiring setup) from cool to heat and back blows the 5amp fuse in the furnace

The original thermostat was wired as follows:

R = red
Y = yellow
G = green
W2 = white
W1
O = orange
X1 = blue

I'm looking at the old thermostat casing and it says:

White Rodgers - Heat Pump Thermostat
2 STAGE HEAT AND 1 COOL

but the new Lux packaging says:

"Not for use on Multi-Stage Heat Pumps"

so am I right in thinking this will never work anyway with the new thermostat?

It can be a York, Luxaire, Fraser Johnston, or Colman/Evcon all exactly the same but come with a different brand sticker on the box. Which was probably thrown in the trash with the box after installation.

Take the blue wire off of the tstat "B" terminal, thats for reversing vale energized in heating I think. Battery operated tstat? No "C" needed.

X1 is X/L for a trouble light when the unit locks out on a safety.

This manual should help:
http://download-v5.streamload.com/6a315867-a101-4604-8bd8-a8de750d3ea0/ciitech/Hosted/EABAF036.pdf

Look at page 10 for low voltage wiring.

thanks - I've since bought a new Hunter thermostat that definitely supports 2 stage heat so I'll give that a whirl

FYI, There been a lot of mixed results on Hunter T-stat.. I'd honestly take it back and get a nice t-stat like Honeywell Vision/VisionPro.

thanks - would any Honeywell be recommended over Hunter? I didn't see the Honeywell Vision at Lowes but there was a Honeywell 5-1-1

http://www.lowes.com/lowes/lkn?action=productDetail&productId=183786-74493-183786&lpage=none

I just picked up the Hunter on aesthetics - (out of the 2-stage heat ones)

I think that one will work. Lowes model numbers don't go with the model that I am ware of. RTH7400D is sold at Home Depot, and few other places.

thanks for the recommendation - I got the rth7400d last night and will try wiring it today

"This manual should help:
http://download-v5.streamload.com/6a315867-a101-4604-8bd8-a8de750d3ea0/ciitech/Hosted/EABAF036.pdf"


I get an "invalid session" error when I try to retrieve that manual - I think it might be subscription only

If you are trying to post the install manual of the t-stat, I got it on my end.

Ok,

Old... color... new.

R .... red.....R (leave jumper to Rc)
Y...yellow...Y
G... green...G
W2...white...Aux jumper to E
O.....orange...O
X1....blue....C

Make sure you follow the Advance set up starting on page 30.

#170 to 7
189 to 2
240 to 3.. (if you use emergency heat, and feel that the temp over shoots, go ahead and move it to 5)

If you got questions on other set up, let us know.

thanks - before I read that I tried something different and it didn't work. I had:

R .... red.....R (leave jumper to Rc)
Y...yellow...Y
G... green...G
W2...white...Aux (no jumper to E)
O.....orange...O/B
X1....blue....E

so main difference was blue... I had it going to E

0170 -- 7
0190 -- 0
0240 -- 9

I didn't have an 0189 option

When I plugged the power back into the air-handler/furnace, the fan came on but I still get nothing from the condenser outside on "cool" - the blades do not spin... I wanted to try "heat" but the indoor temp upstairs was 89f so I'm not convinced I could have upped it to 90f anyway

I don't see any loose wires outside - is there usually a fuse on the board outside too because I didn't see one. Any if so, would I be able to manually turn on power at the little button outside if this fuse was blown?

I ment 180... not 189. Sorry.
You can leave 240 to 9, but lot of people don't like the quick on and off in Emergncy mode.

Make sure you do move the blue wire to C.

If the outdoor unit don't run, did you check fuse/breaker both next to the unit, and the main panel in the home? I never seen a low voltage fuse on the outdoor unit.

Do you have a meter to check power going outside, and also low voltage at the contactor.

I rewired things the second way still nothing.

The main panel is OK and outside I have a little grey box that says "no fuses installed" but there is a metal handle thing that I can pull out to kill the power (I guess)

I do have this multimeter but I'm not really sure how to use it
http://www.avalonrise.com/catalog/images/gd_digital_multimetr_gdt11_b.jpg

Your main fan(inside) does come on when you turn the t-stat to cool, and/or fan switch to ON?

If yes, then you are not getting power of some type outside.

Take the cover off outside where the power goes into, and set your meter to 500vAC, and put on lead on one wire, and other on the other.. You should read 220/240 volts -/+ If you are getting a reading there, then take the lead down to the low voltage wire, should read 24 volts.(system should be calling for cool)

Report back what you find.

correct - the inside fan does not come on if i set the thermostat to off/fan-on. Neither the inside fan nor the outside compresser come on if I set it to cool/auto

Is it safe to touch the prongs of the multimeter directly on the wires outside with everything hooked up?

You- "When I plugged the power back into the air-handler/furnace, the fan came on but I still get nothing from the condenser outside on "cool""

You- "I rewired things the second way still nothing."

Me- "Your main fan(inside) does come on when you turn the t-stat to cool, and/or fan switch to ON?"

You- "correct - the inside fan does not come on if i set the thermostat to off/fan-on. Neither the inside fan nor the outside compresser come on if I set it to cool/auto"

--------------------------------------

Ok, You said fan was on, then said no... I asked if it did come on? then said correct... But then you said does not.???

If the fan don't come on inside, then we have to go back inside....

I think you are now best to call a Pro. sounds like you have not used a meter before.. I'd rather have you be safe than sorry.

yeah - sorry for the confusion.

The way I wired the thermostat up first I got the indoor fan to work but the compresser wouldn't spin. Then I re-wired things so the blue was on C and now neither the indoor fan nor the compresser work

Ok, go back to the air handler and write down what color to what letter on the board.

Post back.

Air Handler
----------

R = 2 x red wires
Y = 2 x yellow wires
G = 1 x green wire
W1 = 1 x white wire also wired to W2
W2 = 1 x white wire also wired to W1
O = 2 x orange wires
C = 2 x blue wires

Also theres a 5amp fuse which upon visual inspection hasn't blown

outdoor unit I sent oliver yesterday which also gives performance ratings for both his outdoor and indoor units.

Typical Field Wiring - 1 PH

Stat indoor outdoor
R R R red
B or C C C blk
Y Y Y yel
O O O org
W W2 W brn
L or X X/L pur
G G
T W1 W1/66 wht
E

E note one - jumper E to W at stat to heat on first stage during emergency heat.

T note two - not used on all thermostats.

Indoor unis=t also has a BK terminal for dehumidification

And out door hase a CC terminal for outdoor stat.