Plumbing and hydronics contractors, do you got a meter?

The weekend was upon us. The phone rang, and I looked at the time. It was five minutes before 5 p.m. What the heck, I thought. I'll make this quick. I should have known better. The voice on the other end of the phone was big and rough. "This is Jack up in Casper, Wyo. I've been workin' on this boiler all week, and I gotta get it goin' before the weekend. Think you can help me"  "I'll try," I replied with caution. "What's the problem?"

Carol Fey | Jan 07, 2014


The weekend was upon us. The phone rang, and I looked at the time. It was five minutes before 5 p.m. What the heck, I thought. I’ll make this quick. I should have known better.


The voice on the other end of the phone was big and rough. “This is Jack up in Casper, Wyo. I’ve been workin’ on this boiler all week, and I gotta get it goin’ before the weekend. Think you can help me?”


“I’ll try,” I replied with caution. “What’s the problem?”


“Bad module,” he declared.  “You know, ignition module. The gray box. I’ve replaced it twice already and they’re all junk. You think you can find me a good one?”


“Well, you know, the problem may not be the module,” I said. “Manufacturers say that 80% of the modules they get back on warranty have nothing wrong with them. Usually the problem is wiring...”  Jack was probably just hearing blah, blah, blah.


He jumped in and said, “I said I got some junk here and I need you to help me.”


There was nothing to do but flow with the bad module theory.


“Jack, let’s check it out,” I said. “What voltage do you have going into the module?”


“The what in the what?”


I asked again, “What voltage do you have?”


 “Enuf!” Jack interrupted. “I got enough.”


Enough? …  I thought to myself.


I said, “OK, you have enough. But humor me for a moment. How much is it?”


“Now how would I know something like that?” Jack cackled.


“Do you have a meter?” I asked.


“Sure,” said Jack. “I got me a meter.”


“Could you take a voltage reading?”


“Nope,” Jack said in a very matter of fact way.


I was a bit stunned by his directness. Then I recovered.



“Well, why not?” I asked.


“Sin the truck,” he stated.


What? I wondered...  Oh, he said it’s in the truck.


“Could you go and get it?” I asked.


Again Jack responded, “Nope.”


“Jack, just in case you can’t find your meter when you do go look for it, may I suggest a couple things about buying one?”


“Sure, can’t hurt,” Jack said.


“You can get a cheap meter for about 10 bucks.”


“That’s all? I thought they were expensive,” exclaimed Jack.


“Not like they used to be,” I said. “But of course, depending on how fancy you get, you can pay a lot. But you need just a simple one.”


“Well,” said Jack. “They’re really hard to use, anyway, aren’t they, readin’ where that itty bitty needle is on all those itty bitty numbers?”


“That’s how it used to be, and those old ones were a challenge,” I said. “But that’s not what we see these days. Those were analog, and that’s not the kind you want to buy.  Now we use digital. They’re easy.”


“Hold your horses, there,” Jack broke in. “I thought digital was always more complicated.”


“Not so with meters,” I explained. “Digital is easy because it gives you the reading in nice big numbers right there on the meter.”


“Well is digital more expensive?”


“A little, but worth it,” I said. “You can get a nice digital meter with everything you need for under $50.”


“Well, 50 bucks is a fair amount of change,” Jack exclaimed.


Kidding, I asked Jack, “How much you going to be spending on beer this weekend?”


“Ok. Ya got me on that one,” he conceded.


I continued, “The other reason to spend the 50 bucks is that they don’t break so easily as the $10 analog model. So it’s going to last longer.”


Jack was sold now. “Where do I get this thing and what do I ask for?” Jack asked.


“Ask your heating supplier for a simple digital meter with volts AC voltage and continuity and that’s all you need,” I said.


“And then what do I do with the thing?” Jack asked.


“Ignore everything except for AC voltage setting,” I said to Jack. “On the meter there will be a letter “V,” for voltage. And it’ll probably have either the letters ‘AC’ beside it or a squiggle above it. Either way, that’s for alternating current. If there are two V’s, pick the one with the squiggle above it. Or instead of that, if there’s a V-A-C, you know, like the first three letters of ‘vacation,’ pick that setting.”


“OK,” Jack agreed. “What’s that mean?”


“Both of those mean AC voltage, or Voltage, AC,” I explained. “AC stands for ‘alternating current.’ That just means it’s house current, the same stuff that comes into any house or building.”


“OK, I got it — Sparky’s stuff,” Jack commented.


I looked at the time.“Yeh, electrician stuff,” I said. “There might be a couple different number settings for volts on the meter. You just pick the biggest number there. That’ll protect the meter.”


I continued, “Now, you said you already replaced the module a couple times this week.  Those modules came in boxes, right? Do you still have one of the boxes?”


“Sin the truck,” said Jack.


“Right,” I said to myself while thinking the chances of there actually being a box in the truck were a little better than there being a meter.


I went on anyway, saying, “Inside the box is a set of instructions. Did you see them?”


Jack responded with, “You mean all that paper in there?”


“Yes, Jack, exactly,” I said. “Inside those instructions, there’s a chart called a troubleshooting chart. It tells you what to do with the meter to find out what’s wrong with your ignition system.”


“Uh, ok, I guess,” Jack said without much confidence.


“No kidding, this will work,” I assured him. “But Jack, this is really, really important.  You have to start at the very top of the chart and go step-by-step. You can’t start in the middle, even if that looks right to you.”


Of course, Jack asked, “Why not?”


“Because you can get the wrong answer that way … and you can’t skip any steps.”


Jack then asked, Even if I know that’s not the problem?”


“Correct! Because what you ‘know’ isn’t the problem might actually be the problem.  Sometimes it’s different than you think,” I said sternly.



Jack then asked me what the chart looks like.


I asked Jack, “Do you have a computer in your office?”


“Uh, I don’t exactly have what you could call an office,” Jack explained. “But my daughter-in-law’s got a computer back at the house.”


“Perfect,” I said with relief. “I’m going to send you a troubleshooting chart, just in case you can’t find it in that box in your truck.”


“Yeh, that’s a good idea,” said Jack. “I was wondering about that.”


“And Jack, I know the weekend’s about to start.” And none too soon, I was thinking…


“One more thing — if you drink a couple beers before you start working with the meter don’t do that. That’ll kill the meter.”


Carol Fey is a technical trainer who has been in the HVAC industry for over 25 years. You can find her books and DVD at  To see her adventures while a heating mechanic in Antarctica, go to

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