gas wall heaters - any experts out there?

[Andy Voelkel]

I've got two wall heaters that need help. On one, it doesn't seem like any gas is coming out of the pilot. On the other, it seems as if the output of the heater has been gradually decreasing over the years.

I'm pretty handy - an electronics engineer by trade - and am interested in trying to fix them myself, especially after dealing with a couple of local heater guys who want to replace the whole units without really debugging the problem. I don't mind spending the money so much, I just don't want to screw up my walls and paint, etc. It also seems like a little intelligent troubleshooting could actually save labor costs.

Any advice on how to debug my problems would be greatly appreciated. What would be _super_ would be pointers to any websites or publications that describe operation and design of these sorts of heaters (as well as other home appliances, BTW).

Thanks in advance for any help!

- Andy Andy Voelkel 310 399 2289 [e-mail]

[Dennis J Sunday]

Andy, Have your gas company test and verify supply pressure. I have most experience with LP measured at the appliance should be 11.0" water column. You would need a manometer to measure. The unit with the "no gas" at pilot, you need to disconnect pilot supply tube to verify gas flow, if ok - pilot orifice may need to be cleaned. You can only clean with proper size "drill", we use to use a broach which measures out about the size of a human hair in diameter. If you oversize pilot opening you will have to replace orifice, Once the pilot is functioning, it should light and holding main valve should keep pilot lit and allow you to rotate to "on" position. With unit calling for heat, you should get ignition. If gas units have not been used for a long time: check for animals and nests in the firebox and vents. Check for spider webs in the pilot orifices and burner tubes.

[Dave Harnish]

Hi Andy,

Dennis has supplied some good info on these. I see the occasional spider or even dead fly in ours, and since I don't use it through the summer, there's nearly always a little 'critter' to clean out in the Fall. A byproduct of burning LP is water vapor, and this tends to cause corrosion buildup, as well.

I use our pilot broaches alot, but they're pretty expensive. Years ago, before I found them, I used a single 'thread' of stranded copper wire. Lamp cord worked well on smaller ones, hi temp range wire strands (nickle-plated) on larger. More fragile than a broach, but a lot less $, and with a little patience, does a passable job. There's also less chance of ruining an orifice by broaching it out too big, bc the copper won't remove metal like a broach.

These heaters use pretty straight-forward control systems, but one problem is finding parts, especially for older heaters. Some of the brand names seem to come and go so fast it's really tough to find exact parts.

Mine here in the shop/office is a good example - it's an 'Alvima', and since I've had it for nearly 20 years, I'm not planning on repairs if it fails, unless it's something simple.

Anyway, hope that helps a bit. As far as publications on other appliances, you might be interested in my free monthly newsletter. I've been an appliance tech for 31+ years and really enjoy sharing unusual tips & tricks of the trade with anyone who's 'handy'. No obligation, no strings, you're welcome to sign up (and every issue has an unsubscribe link). Details are below.

God bless,

Dave Harnish Dave's Repair Service New Albany, PA [e-mail]

570-363-2404

I'm a 30-year pro appliance technician, and love sharing what I've learned - in a FREE Monthly Appliance Tips Newsletter:

Acts 4:12

[TURTLE]

This is Turtle.

i am still look to hear what type heaters you have. A brand or model number would be nice but you can describe the things I list below and it will tell what type systems you have.

1) Does it have selector switch for a fan to blow air into the room or not ? 2) Is there 120 volt electric service coming to it ? 3) When looking at the pilot lite does the thrmocouple look kind of fat like 1/2" big around and about 2 ' long where the flame is suppose to hit it or is the thermocouple small and thin like a thermocouple like a hot water tank thermocouple ? I need to know so I can tell what system you have. 4) Is it fueled by Natural gas or propane / LP ? 5) On the heater that the pilot lite seem not to work. Will the pilot lite ever light at all or just light and when you let go of the button the pilot lite will go out. I need to know which it is. 6) Are these wall furnaces are in one unit with one side in one room and the other in the other room ? Or they totally seperate systems in different parts of the house? 7) Do they have a thermostat on the wall or control by a knob on the heater it'self ? 8) Go out side and look at the Gas meter and see if the shut off valve for the meter is open wide open ? 9) Does the gas valve have somewhere on it stamped ITT on it anywhere? 10) Look at the roof at the pipe for vent gas to leave the roof and see if the vent cap is not mashed down and cutting the burn vapors off from coming out? 11) About what year was these heater made / bought / can be in blocks of 10 years like 10 , 20 , 30, or 40 years ago?

Here is your start!

TURTLE