Has anyone replaced burned out bulbs in their HVAC control?

Only some of the buttons are lit on my HVAC control.
Has anyone taken this unit apart to replace burned out bulbs?
Anyone know what type of bulbs are used?

For my radio which is also partially dark, I found the write up on replacing those bulbs, and imagine the HVAC unit is somewhat similar.

albertj wrote:

I just did my button bulbs. In a way they were easy, in a way they were a P I T A.

The only changes I have to the directions are as follows:

1) go to a craft store and buy some turquoise glass paint. I bought Vitrea 160 glossy marker, in turquoise. Stock number 116084. At Michael's. It is the PERFECT color for the dash lights.

2) get replacement bulbs. You will need six 12v 'grain of wheat' (Radio Shack 272-1092) and one 12v bi-pin (Radio Shack 272-1154). The grain of wheats are a substitution, the bi-pin turns out to be an EXACT replacement. T1-1/4 packaged 14V bi-pins are what's in the control OEM, but I only found them on EBay and so many of my bulbs were out I decided not to wait. What you really want are either #2182 or #7382 lamps. If you live in a major city (I don't) you may have an electrical supply house nearby like Newark that stocks them. They will be cheaper on EBay.

3) you will also need some dry gas (read the label - get the CHEAP stuff, it's just isopropyl alcohol) or health-and-beauty-section 91% isopropyl alcohol - try WalMart, CVS or RiteAid. And some q-tips if you don't already have them.

4) you need to know how to solder; you need normal electronic shop supplies (a 1/8" and a 3/8" hexhead socket drive; a pencil-type soldering iron; rosin-core solder; also maybe a solder sucker or desoldering wick and a static strap for your wrist so you don't accidentally kill the control IC)

Anyway... to replace the bulbs:

a. open the climate control as described in this thread BUT if your climate control has not been serviced already you will find two (probably black) 3/16 self-tapping screws, they are black, on the outside corners of the case opposite those tabs. The self-tappers on the board inside are 1/8" by the way.

b. What you need to do now is desolder and remove the bulbs on the board and replace them with the new bulbs. To do this have to open the face of the control by taking out two (probably silver) self-tapping screws with 1/8" hex heads. Be careful that the button faces don't spill out of the frame when you do this. And before you do that, please read the following details:

- If your board has not been serviced before the bulbs are little blue things, they look like LEDs but they are not, they are 14V #7382's with little blue covers (like mini-condoms) on them.

- you probably want to do this replacement one bulb a a time. When you solder the new bulbs in place, if you use grain of wheats instead of the #7382s, be sure to solder them in such that the filament is about the same level as that of the filaments of the bulbs you removed. basically this means the grain of wheat bulbs get installed with leads extending something like 3mm from the circuit board. If your unit has not been serviced before you will find one bulb with a little red sleeve (like a hose) around it. Replace that one with the Radio Shack 272-1154 (the t1 bi-pin, it is an EXACT replacement!) and transfer the little red sleeve to it. If your unit has been serviced before you can try painting all but the tip of the 272-1154. Leave the tip clear so it projects a dot of white light onto the back of the red arrow on the control panel. You guessed it - this is the bulb that makes the arrow in the climate control light up red.

Yay. You are done with the bulb replacement - almost. Turn the soldering iron off - unplug it or whatever.

Now here's where it gets interesting.

c. clean off the new bulbs, in place, with a q-tip dipped in alcohol, wipe off with a paper napkin or facial tissue. Then wipe them again with the alcohol q-tip and allow to air dry (takes only a moment, the 91% alcohol evaporates real fast).

d. using the vitrea paint pen, evenly coat the now-dry bulbs (EXCEPT the one with the red hose on it) with the paint, and allow to air-dry (takes around 1/2 hour). Do not double-coat the bulbs, they are not that bright to begin with. Do not color the bulbs before installation, because your fingers will take the color back off unless you cure it (350 deg. F for 1/2 hour) first. Color them after installation and let the heat of the bulb bake the paint.

e. when dry, put the switch membrane back on the circuit board and reasemble the board into the case.

f. reinstalll the control head in the dash.

Helpful hint: when you do this replace all the bulbs, because the jostling back and forth will probably bust the filaments that are not already burnt out.

The paint bakes onto the bulbs and be comes hardened (and resistant to most household chemicals) after about 1/2 hour to 1 hour of use.

If you need further details please post here or send me a PM.

Albertj

From another thread.

Got to the search window and type"HVAC Control Pane"
There is 2 page write up there also.

Geez, I tried all kinds of search terms and came up empty handed.
Or, too many irrelevant posts to wade through.

I thought I might have been the first to ask the question.


Thanks for finding those for me!

No problem, friend. Is that your '70 Riv in the signature?

captshiner wrote:

No problem, friend. Is that your '70 Riv in the signature?

Yep! that's my '70. and those were brand new BFG Radial TA's!

My wife just happened to see the photos, gave me the look and said.
"Don't you dare say you need for new tires again anytime soon!"


That '70 has been a work in progress for some time now.
I got a case of the "While I'm at it's."

I started out removing trim for a paint job, but found I had to remove the front fenders to get that portion of the sweepspear trim off.
(The assembly manual shows it is held on by push clips, but all these cars seem to have studs and nuts running the whole length of the fender.)

I then said to myself, since I have the front clip off, it would be easy to pull the engine and detail everything "while I'm at it."

Then, once I had the engine out, I said, I might as well rebuild it "While I'm at it".
So, that is all done now and the car is now sanded down and waiting warm weather again so I can finish the paint job I started a few years ago.

Sweepspear wrote:

Geez, I tried all kinds of search terms and came up empty handed.

The search is kinda busted. Use 'Advanced Search' and let google do the searching. Much better results.