Another crawl space heat question...Electricians?

[Lakesrider]

I need a good electrician to quote me a price to heat a crawl space. 40' x 25' ish. about 4' high but split in two with a wall in the middle. Big hole in the wall to crawl through.
We had been using an electric space heater....240V style garage heater, on one side and a small milk house heater on the other...to heat the space previously. But that to me was not so safe. I certainly do not want to be responsible for a fire, so I need someone to get me some heat under there.
Anyone know anyone?

This is what happened to the cord on the last heater.....See what I mean? This never tripped the breaker! Yikes!

[ITD]

Probably wasn't overloaded more likely a bad connection due to loose wire or corrosion or wrong wire type for receptacle. Could do it yourself if you are handy.

[DickR]

Yikes is right, with that outlet damage so close to unprotected EPS foam nearby. You might think about protecting that foam with something. Current code says:
"...all foam plastic insulation must be separated from the interior of the building by an approved 15-minute thermal barrier, such as ½-inch gypsum wall board or equivalent material. This thermal barrier may be omitted if certain conditions are met in attics and crawl spaces. Specifically, entry must be restricted to service of utilities AND the foam plastic must be protected from ignition with a code specified material.

Section 316.5.3 of the IRC prescriptively defines the
following six materials as ignition barriers:
• 1½” mineral fiber insulation
• ¼” wood structural panels
• ⅜” particleboard
• ¼” hardboard
• ⅜” gypsum wall board
• 16 mil corrosion resistant steel

[Rusty]

For the circuit breaker not to trip with a burn like that, there could have been a GFCI receptacle up stream that tripped which in turn shut off the electrical flow. Did you notice that one of your GFCI receptacles had tripped.

[songkrai]

My "Milkhouse" heater did the same exact thing.

Mine was an older Milkhouse heater. The wire/cord became brittle over the years and a couple of cracks developed on the plastic coating of wire that plugs into outlet.

I used it for years in same place. This fall it worked sometimes. Then stopped working. I thought that the heater was broken. When I looked at plug (behind desk) I viewed same as picture above.

I cut cord/wire and put new plug on heater and it works fine. But it is now in storage as I purchased a new one.

[Lakesrider]

Yikes is right, with that outlet damage so close to unprotected EPS foam nearby. You might think about protecting that foam with something. Current code says:
"...all foam plastic insulation must be separated from the interior of the building by an approved 15-minute thermal barrier, such as ½-inch gypsum wall board or equivalent material. This thermal barrier may be omitted if certain conditions are met in attics and crawl spaces. Specifically, entry must be restricted to service of utilities AND the foam plastic must be protected from ignition with a code specified material.

Section 316.5.3 of the IRC prescriptively defines the
following six materials as ignition barriers:
• 1½” mineral fiber insulation
• ¼” wood structural panels
• ⅜” particleboard
• ¼” hardboard
• ⅜” gypsum wall board
• 16 mil corrosion resistant steel

Yeah I know. this is a really old building and that was done way before i started there. I planned to drywall all around the utility section. Access is limited to just me and any service personnel.
It's getting a bit late to wait to get this done.....I'm getting nervous about the pipes.:eek:

[HellRaZoR004]

Yeah I know. this is a really old building and that was done way before i started there. I planned to drywall all around the utility section. Access is limited to just me and any service personnel.
It's getting a bit late to wait to get this done.....I'm getting nervous about the pipes.:eek:

Yeah - it got cold last night.

[SIKSUKR]

If that was my setup, here's what I would do. If you don't need to plug an unplug the heater for moving it around purposes I would hard wire it. Very simple actually and you could use that existing box. Cut back the wire to where the insulation is not brittle anymore from the overheating, which is caused by either a loose plug connection or loose wire on the plug itself. Make hard connections with good solid twisting and firmly twisted wire nuts. The less possible loose connections, the better. This is when arcing occurs and in turn what you ended up with assuming all wire is sized properly for that load.

[Lakesrider]

Well I think I found the issue. It seems the electric space heater was rated at 30amps. Someone cut off the plug and changed it to a 20 amp 240 volt plug. The breakers are only 20amp and the line is a 12/2. So it was overheating the plug I think.....well I know obviously. The last heater was a 5000 watt type. So last night I headed up to the North Conway Lowe's and got a new 4000 watt 20 amp heater. A Farenheat garage heater. I will install it and see how that goes. Most likely keep it on the low setting. I can raise it to the higher setting if it got really cold out like it does sometimes. I just have to remember to do it!
I did put some drywall above the heater to protect that foam. Also after looking around at the foundation it did seem pretty tight. I could not see any light coming through anywhere, so hopefully that is a good thing.
Talk about spider webs in there......yuck!:laugh:

[SIKSUKR]

That probably was NOT your problem. If the heater was drawing 30 amps and not tripping the 20 amp breaker, you better look at that breaker asap. If the plug was cut off and a different one installed then most likely the connections were not tight and arcing was occurring. Don't just go plug your your new heater into that receptacle. I assume you changed that one out cuz its toast. More than likely the wires supplying it were overheated also and the insulation damaged. Make sure to cut back to good soft insulation and install the wire to terminals tightly.

[ITD]

I agree with SS on this, that breaker should have tripped if the heater was on full power. I also think there was a loose connection somewhere. I wouldn't trust that breaker knowing this.

I also would have an electric baseboard with a thermostat hard wired in, it might cost a little more up front, but I think having the heater on a thermostat will save you in the long run. I looked for a plug in thermostat for you , but was only able to find 120V.

Good luck.

[Rusty]

Well I think I found the issue. It seems the electric space heater was rated at 30amps. Someone cut off the plug and changed it to a 20 amp 240 volt plug. The breakers are only 20amp and the line is a 12/2. So it was overheating the plug I think.....well I know obviously. The last heater was a 5000 watt type. So last night I headed up to the North Conway Lowe's and got a new 4000 watt 20 amp heater. A Farenheat garage heater. I will install it and see how that goes. Most likely keep it on the low setting. I can raise it to the higher setting if it got really cold out like it does sometimes. I just have to remember to do it!
I did put some drywall above the heater to protect that foam. Also after looking around at the foundation it did seem pretty tight. I could not see any light coming through anywhere, so hopefully that is a good thing.
Talk about spider webs in there......yuck!:laugh:

Am I correct in understanding that you have 12/2 wire going to a 20 amp, 120 volt breaker for your heater?

What is the voltage for the new 4000 watt 20 amp heater that you bought?

I'm a little confused about your statement: "Someone cut off the plug and changed it to a 20 amp 240 volt plug". Was the heater 240 volts?

[Lakesrider]

Sorry. No. What I had was a 30 amp breaker on a 12/2 wire. Someone installed a 20amp 240V outlet, then cut off the 30 amp plug on the cord and installed a matching 20amp 240V plug. So the plug over-heated and melted. I thought it was a 20 amp dual breaker because it was labeled Basement heater. Well come to find out The 30 amp was on. Not labeled. ( I did relabel everything) I found that out by the tingle in my right arm when I touched the white wire and the ground at the same time. Now I had tested the wires with my meter and got nothing. It seems one side of the 30amp dual was burned out but the other side of it was not.. I bought a new 20 amp ( to replace the 30Amp) dual breaker, new outlet, and installed a 20 amp 4,000 watt heater. It has been running fine for the past few days. I did add drywall to the ceiling for a good portion of the area around the heater too. Nice and warm in there now. I have the heater set to the low setting which is only 9,000 watts.

[Rusty]

Sorry. No. What I had was a 30 amp breaker on a 12/2 wire. Someone installed a 20amp 240V outlet, then cut off the 30 amp plug on the cord and installed a matching 20amp 240V plug. So the plug over-heated and melted. I thought it was a 20 amp dual breaker because it was labeled Basement heater. Well come to find out The 30 amp was on. Not labeled. ( I did relabel everything) I found that out by the tingle in my right arm when I touched the white wire and the ground at the same time. Now I had tested the wires with my meter and got nothing. It seems one side of the 30amp dual was burned out but the other side of it was not.. I bought a new 20 amp ( to replace the 30Amp) dual breaker, new outlet, and installed a 20 amp 4,000 watt heater. It has been running fine for the past few days. I did add drywall to the ceiling for a good portion of the area around the heater too. Nice and warm in there now. I have the heater set to the low setting which is only 9,000 watts.

WOW!! 12/2 wire going to a 30 amp dual breaker. You are lucky that the only thing that happened was a burnt outlet.

Now you have a 20 amp dual breaker that goes to your 20 amp 4000 watt heater. So my question is: What do you have hooked to the other side of the dual breaker? Do you have a dual breaker because you ran out of room in your panel for a single pole breaker?

[KDL]

I agree, permanently installed baseboard heat would be the way to go. I would install an 8' high density 2500W, or two 5' 1250W units on each side, with it's own thermostat and own 15A 240V circuit. Two of everything would give you redundancy in the unlikely case one would fail.

A 20A circuit for a 4000W heater is under sized, especially for a cord and plug connected heater.

[Lakesrider]

It is what was called for in the instructions. It only draws 16amps at the high setting and I am leaving it on the low 1500 watt setting. Sorry not 9,000 like I posted above.
Been several days and it is still fine.
I won't do anything else to it. I will get a lic electrician if it should need more work.

Can't have a single breaker on 240V. Needs two legs so a double breaker.

[SIKSUKR]

Double pole breaker.

[willcastner]

Looks like you got lucky there. With a crawl space of basement there is a few different ways to insulate. if there are plumbing pipes or heating system down there the walls should be insulated. Many people insulate the ceiling of a basement or crawl. In MOST cases this is the wrong way. By insulatiing the ceiling you are pushing the plumbing and/or heating system out side the heating envelope. This cause efficiency/comfort issues due to unused heatloss from any heatsource and pipes to freeze.

This can be something you can address and often times by fixing eleminate the need for a heater down there all together.