Electrical Emergency

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Above are two pictures of a house’s service drop–where the electrical supply arrives from the street.  Standard 240 volt electrical service has three wires entering the home.  Two are ungrounded conductors on which travel the two (120 volt) legs of the electrical supply.  The third grounded (neutral) conductor allows the circuit to be completed back to the transformer outside the house.

The problem here is that the grounded service neutral is disconnected!  This is a very serious electrical defect.  Power was on in the house.  For there to be power, a circuit from the transformer and back must be completed.   But with service neutral disconnected, power must be returning some other way to the transformer–Through the ground or plumbing.

Crawlspace Adventure

Every crawlspace is an adventure.  I don’t see that many in Pittsburgh, mostly basements and so I don’t know if that biases things, but often Pittsburgh crawlspaces are a mess.  In the older houses I spend all my time in, a crawlspace exists in because it was an addition they hit rock and gave up digging or both.  Below is the entrance to the crawlspace.  Image

Can you see the knob and tube?  This crawl space is original to the house. DSCN2634

It is a stone foundation.  Above, the foundation stones were in disarray, water from a roof leak had eroded the mortar between the stones and rotted the end of two joists–someone shimmed a joist at the top of the photo.


Above is knob and tube wiring is frayed and degraded.


It’s raining in the attic with out a cloud in the sky.

I see it all the time. In the picture below, there are drip marks on the floor of the attic.  This is a winter phenomenon where warm, moist air from the living space leaks into the attic and condenses on the cold surface of the roof sheathing.    


Bellow the insulation is pocked from water dripping from below.  


The pattern of drips is frequently from the nails in the sheathing.



Over time the moisture condensing in the attic damages the sheathing.  Plywood and OSB siding are the most effected by the moisture, older houses with plank sheathing don’t seem to degrade as much from this condition.  The most common type of house is ranch house with truss framing and plywood sheathing.  The plywood used for trusses in the 60’s and 70’s was sometimes only 3/8 inch thick.  When the plywood degrades enough, it needs to be replaced when new shingles go on.  It feels soft when I walk on it and it may not hold nails.  


The Trusses above and below are rusted at the gussets and need a structural engineer to review to make sure they still have their structural integrity.  Some times, when new shingles are put on, the roofers don’t remove the old, damaged sheathing and just add another layer of sheathing over the top of the old sheathing,  This is a bad idea.


But what about the causes.  First, moisture laden air leaking into the attic. It gets in through an unsealed, uninsulated attic hatch or better a pull down stairs.  Bathroom vent fans frequently are vented into the attic instead of to the outside through the roof.  Air also leaks through the openings around lights and electrical fixtures in the ceiling, especially recessed lights.  

That is part one of the cause–the air leaks into the attic.  Part two is a lack of ventilation in the attic that prevents the air to vent out before it condenses.  


Fix It Now! Electrical Edition

In Pennsylvania, a home inspectors primary job is to find “material defects”.  A material defect, as defined by Pennsylvania law, “is a deficiency in a component of the house that will significantly lower the value of the house or that poses a threat to the health or safety of its occupants.” Below is a picture of an old fused service box and two sub panels that should have been replaced or upgraded years ago.  Fuse boxes are fine.  Fuses can provide as good or, some say, better over-current protection than circuit breakers, but these panels are simply too small for the demands of the house, which now has central air and a rear addition.  Instead of putting in a new panel, the home owner added circuits any-which-way, creating a dangerous situation.


With out the covers on you start to see a lot of defects.DSCN2266First off, in the upper left corner, the main feeds from the meter are scorched,  and the lug on the black conductor is melted completely.


Overheating wires–top left


Multi-taps–not enough terminals for all the wires.

At the bottom of the panel, terminals are double and triple tapped for lack of enough places to connect a terminal.


Double tap in the sub panel

The sub panel is also over crowded with double taps and the fuses are all 30 amp fuses which are too large for regular household circuits.

But back to the scorching at the top of the panel. The scorching is upstream of the fuse blocks, which is to say, it is overheating in the service entrance cable before the fuse where the fuses can’t blow and turn off the power.

This service entrance cable was newer where it leaves the meter box.  Generally, it is easy to guess the location of the panel while standing outside: its within a few feet of the meter on the inside of the of the wall–” as close as practicable” says the code.


Newer service conductors below meter.

But at this house, the S.E. cable travels about 30 feet hidden in the ceiling before it connects to the panel. And if you look at the cable as it enters the panel, it is an old cable.  So the service entrance cable is spliced somewhere in the ceiling.


Old, frayed service cable on top left.

The long run of the service entrance cable should be protected by a circuit breaker at the meter, but then the panel would be a subpanel, not a service panel…and that is another story.


These meters each have a disconnect in the black compartment to the left of the meters that protects the service feeds that go out the bottom and travel to the panels in the house.

A Water Heater For The Ages

Perhaps it should be an axiom of water heater performance–that the older it is, the longer it will last. Water heaters from the 60’s and 70’s or even the 80’s could last 20 years.  Not always of course. Today’s conventional water heaters are designed to last 8-12 years.  I see them failing before 6 years all the time.

Water heaters may come with warrantees–5 or 10 years.  It is usually the same water heater but you pay more for the 10 year warrantee.

But the point of this post is this:Image

This Ruud water heater is still working!  It was probably manufactured in about 1931, the year the house was built.


Edwin Ruud designed and patented this gas powered unit around 1900 while working for George Westinghouse (of course) at the Fuel and Gas Manufacturing Company in Pittsburgh. The design is for an instantaneous water heater that uses a system of coils, rather than a tank, to heat the water as it passes through the water heater.


It really should be replaced since it does not have the safety features that modern water heaters have.  Primarily the pressure/temperature release valve, which eliminates the possibility of the water heater becoming a rather large bomb.

But it sure says something for the quality of construction from another era.  I peeked on ebay and I saw similar Ruud’s selling from $250-750, which would be nearly enough to pay for the replacement.  Hmmm.

The Problem With High Efficiency Furnaces

A “high efficiency” furnace is a furnace that is 90% or more efficient.  The trick to getting this efficiency is a second heat exchanger that condenses the moisture contained in the combustion exhaust and thereby capturing much more of the heat that would be lost up the chimney with mid-efficiency (80-85%) or conventional furnaces (50-79%).


The problem is that now the furnace produces condensate, the acidic liquid that goes up the chimney in less efficient furnaces.  The condensate goes through a variety of hoses and drains, and then, if everything works right, it ends up in a drain or laundry tub.

But if one of the tubes or pipes leaks, the condensate will end up somewhere in the furnace compartment and start rusting–it’s quite corrosive.


Leak in the PVC vent pipe.




Attempted patch with caulking. It might hold for a while, but probably not very long.


Common leak at the fitting at the inducer fan.


The longer the leak goes, the worse the damage.

leak where a hose clamp is missing.

rust below where a hose clamp is missing.

Anytime you see moisture around the furnace, immediate repair is needed.

Anytime you see moisture around the furnace, immediate repair is needed.

Much of the time, these condensate leaks are repaired and the furnace continues to function as normal.  But if the leak is not coming from a hose, and instead from, for instance a screw for the access panel that holds the secondary heat exchanger, then there may be a larger problem–a failed heat exchanger.  If the heat exchanger is damaged, you need a new furnace.

220, 221… Whatever It Takes

I think that’s the quote from Mr. Mom–Michael Keaton was talking electrical.  In the United States, most smaller electrical requirements are satisfied by 120 volt circuits and larger demand appliances like clothes dryers or stoves use 240 volt power.

Typically, residential service from the street has 3 wires (conductors).  Two of the wires (ungrounded conductors) carry 120 volts each, the third is the neutral (or grounded) conductor that the current returns on to the source–a transform.  When you put them together you get 240 volts.


The house below had an old old electrical system



The service cable only has two conductors entering the house, so only 120 volt electric power is possible in the house: no electric dryer, central AC, baseboard heat, electric stove, are possible.


The capacity of a residential electrical service is usually 100-200 amps, this house was a 30 amp service, that is to say, the service conductors were 10 gauge wire with a 30 amp main fuse.  But as you can see, there were two meter sockets (kind of new ones) and two separate electrical services in the house all from the 30 amp two wire service in the first picture.


Of course, the wiring in the house was all knob and tube wiring–seen above meter sockets.  Knob and tube is the original method of wiring installed in residential houses.  By now most of it is antiquated and ready to be replaced: the wire insulation gets brittle, people tap into the wires in inappropriate ways.  Basically the older an electrical system is, the more chances there are for someone to make a crazy modifications.


The above picture shows someone’s misguided attempt to add a grounding electrode system: a copper wire loosely wrapped around a water pipe.    The type of grounding attempted here is earth grounding, which is for electrical surges (like lightening) to go to ground, but I doubt this installation would have any effect.

DSCN4451DSCN4464Finally, the last two photos are of the old push button light switches.  They usually mean that knob and tube wiring is still in use in the house.