Electric furnace wiring temps

[David Meiland]

I have absolutely nothing to go on here--just snapped some images because I had the imager in my hand, and looking for comments.

This is a "Wesco" electric furnace in a 1950s ranch house. It's fed by a pair of 50-amp breakers and was drawing roughly 11 Kw, based on clocking the meter, no amp clamp used. I was impressed by how hot these wires and connectors get. I recognize that they feed the elements, but it still seems high. Also looks like only one (two?) of two (four?) elements is working?

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[Marc]

Have you got a visible spectrum photo of it, without the IR overlay?

I see plenty enough to recommend an HVAC guy examine ALL power connections.

Marc

[Jim Katen]

I have absolutely nothing to go on here--just snapped some images because I had the imager in my hand, and looking for comments.

This is a "Wesco" electric furnace in a 1950s ranch house. It's fed by a pair of 50-amp breakers and was drawing roughly 11 Kw, based on clocking the meter, no amp clamp used. I was impressed by how hot these wires and connectors get. I recognize that they feed the elements, but it still seems high. Also looks like only one (two?) of two (four?) elements is working?

Click to Enlarge

38.2?KB

When they're running, the elements will get cherry red, like toaster wires, so I'm not surprised that the connection to the element gets very hot.

That's a 20kw furnace and only two for the elements are working at the moment of the picture. The two non-working elements might not have seqenced on yet, or their sequencer could be bad, or the coils themselves could be damaged. 5 minutes with a multimeter could tell you exactly what's going on.

[David Meiland]

Here's a visible light image.

I'm not an HVAC tech and was only there to check out a high electric bill for the utility. There was very little air coming out of the registers. I opened the cabinet to make sure there wasn't anything blatantly wrong, like a dead body blocking the airflow. I wouldn't know where to start with a multimeter. Sometimes I put an amp clamp in the panel to see what a system is drawing, but that's usually when I want to know if a heat pump system is operating the heat strips in warm weather (which is very common around here).

There were major problems here. Warm air was gushing out of the floor hatch to the crawl space. I couldn't get more than a few feet into the crawl, because ductwork was blocking the way, but I suspect a disconnect somewhere down there.

The most amusing thing--this furnace once supplied a detached garage a few feet from the house, as well as the house itself. There had been a supply duct running through the great outdoors from one attic to the other, now removed. There was a return duct sucking air from outdoors in the gable of the house, in addition to a couple of returns in the house ceiling.

The tenant has been paying >$400/month for electric heat and has been freezing.

Click to Enlarge

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[Marc]

Here's a visible light image.

I'm not an HVAC tech and was only there to check out a high electric bill for the utility. There was very little air coming out of the registers. I opened the cabinet to make sure there wasn't anything blatantly wrong, like a dead body blocking the airflow. I wouldn't know where to start with a multimeter. Sometimes I put an amp clamp in the panel to see what a system is drawing, but that's usually when I want to know if a heat pump system is operating the heat strips in warm weather (which is very common around here).

There were major problems here. Warm air was gushing out of the floor hatch to the crawl space. I couldn't get more than a few feet into the crawl, because ductwork was blocking the way, but I suspect a disconnect somewhere down there.

The most amusing thing--this furnace once supplied a detached garage a few feet from the house, as well as the house itself. There had been a supply duct running through the great outdoors from one attic to the other, now removed. There was a return duct sucking air from outdoors in the gable of the house, in addition to a couple of returns in the house ceiling.

The tenant has been paying >$400/month for electric heat and has been freezing.

Click to Enlarge

45.18?KB

Sounds like the ductwork is your culprit. As for the IR revelations, two conductors bringing power from a breaker to the two upper elements both indicate elevated temperatures at one end but only one has it at the connection to the element. The other one has it at the connection to the breaker. In my mind, this eliminates the heat-from-the-element angle.

You've an issue with poor connections.

Marc

[David Meiland]

My initial take on this was high-resistance connections. I've been pondering whether or not I know a HVAC guy who could determine that.

I shared my concern with the owner's contractor, who lives a few houses down. He turned off the breakers to this unit. I advised the tenant that she could get cheaper heat from space heaters, so she started calling friends to borrow some. Tomorrow morning I'm going to call the owner and explain what a mini-split is.