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Yankee802
10-31-2008, 03:10 AM
Ok, I don't know if this is normal, so here goes.

I can't run the 3 electric heaters without the breaker going off. I have 2 toe kick heaters inside, and one in the basement to heat the watertank bay. What confuses me is that I can run all 3 AC units, but not all 3 heaters? I watch the amp meter and the breaker pops at 34amps, doesn't the AC use a lot more than that?

Geoff

dalej
10-31-2008, 07:01 AM
Geoff,

Turn one on at a time and check to see if one is pulling to many amps.

Jon Wehrenberg
10-31-2008, 07:28 AM
The current draw seems right. A 1500 watt heater has a draw of about 12.5 amps (less if the voltage is greater than 120).

But which breaker is tripping? The one on the shore power?

And yes the AC units use slightly more when running, and a lot more during the start momentarily. If the problem is with the shore power either the terminals are loose on the CB or the CB is bad and needs replacing. A 50 amp breaker should be able to carry 40 amps on each leg continuously.

Are you sure that on the leg with the 34 amp current draw that you don't also have some occasional loads like a hot water tank, or a block heater?

Joe Cannarozzi
10-31-2008, 07:50 AM
The squirrel cage on a couple of mine were stuck from age and prolonged non use. By simply removing the grate cleaning them with a vac manually giving the cage a spin to get it started and using them more frequently they now work.

There are 4 or 5 heating elements in each one and I have a couple in one unit or another that have failed. If you look in with the grate removed you can tell because the bad ones will not be glowing red. Noticeable difference in performance too.

Mine are made by Dayton and you can get them at Granger.

BrianE
10-31-2008, 10:56 AM
If you determine it's a heater, and considering the age of your coach.... Maybe you should consider removing all of the towkicks for cleaning, lubing and benchchecks. Would also consider similar checks and hose replacement of all under cabinet hot water heaters such as Webasto heat exchangers if installed. I replaced all of the underfloor hoses and the Webasto heat exchanger motors in Tom's Liberty. Interior leaks and or heater fire possibilities aren't much fun to contemplate. These are pretty easy projects which yield much piece of mind.

Yankee802
10-31-2008, 02:42 PM
My toe kick heaters are on a 20 amp breaker, and each AC is on its own 30 amp breaker, so I guess that answers my question, but WHY would they have put all 3 heaters on one breaker?

I set my basement heater to 40 (degrees?) lastnight, and it was just above freezing outside. Later in the night, the floor was pretty warm in the hallway next to the bathroom (right above the heater). I went to check and it was 167 degrees on the ceiling/floor, and around 70 in the tank area where the temp sensor is located for the heater. I thought the heater would kick off once 40 degrees was met, guess not. Awhile ago I saw a post in here for remote temprature sensors, but I can't find it, can someone post a link to it here?

I'm working on replacing all of the vent filters and cleaning everything I can get to, but I don't have the knowledge to check and replace all the hoses and pipes. The previous owner said he did some extensive work with the Webasto, and it seems to work pretty good, so I'm hoping I don't have to worry about that. BTW, does anyone know the average fuel comsumption for our Webastos?

I'll try to do what Joe said about the Wabasto squirl cages, the one in the bedroom puts out heat, but it's like there is not a fan behind it to push the heat out into the room. Hopefully I can access it. If it's like my galley AC, (sounds like a fan bearing is going out) I have no way to access it without taking apart my kitchen.

Geoff

Jon Wehrenberg
10-31-2008, 03:18 PM
Geoff,

Marathon is a very respected and responsible company. I find it difficult to believe they have more heater current draw than the breaker is rated to handle. You still did not answer whether it is the shore power CB tripping or the one in the bus.

I have had the type commonly used in buses fail, one because the screw holding the terminal in place had loosened and the arcing burnt the tab on the CB, and another the CB just tripped because it had failed.

If you have a heater making surfaces in your coach reach 167 degrees you will get burned touching those surfaces, but more importantly that tells me something is wrong, like a fan not working or a thermostat which has failed.

Generally toe space heaters have the temperature thermostat and a second thermostat located above the heating element. The temperature control thermostat sensor is usually in the return air flow and is used to regulate room temperature. The second thermostat is to shut off power to the heating element as a safety in case the fan fails. With no air flow across the coils the heated air rises and trips the safety thermostat.

On my toe space heaters there is also a fusible link. If temperatures get too hot, that opens and effectively kills the heater until the link is replaced.

Being a cynic I would open each heater up to clean them, verify things are OK and to make sure some previous owner has not bypassed all the safety controls such as the thermostats. I would also verify which bus circuits power the heaters.

Yankee802
10-31-2008, 03:26 PM
Jon,

It's the CB in the bus, it's a 20amp and I don't know how to check it, so I guess it could be loose or bad. The basement heater could have a bad sensor I suppose, don't know how to check/verify that either, any suggestions for a noob? :)

Geoff

Jon Wehrenberg
10-31-2008, 08:13 PM
Geoff,

Step one, go out and get a six pack of a decent brew. Put it on ice.

Step two, make friends with someone that is comfortable with electricity.

Step three, bribe him with beer (see step one) to help you.

All kidding aside, I am not comfortable trying to direct someone how to analyze a 120 volt heater that has the potential to both electrocute you or burn your bus to a crisp. These are simple devices, likely plugged into a receptacle located out of sight behind where the heater is installed.

They can be removed and easily inspected and cleaned, but only by someone who is comfortable with simple electric circuits and is willing to use a multi-tester to verify the thermostats are working, the fusible link is in place and working and the heating element is working. Cleaning it and checking the fan operation is all that is necessary if all else checks out.

As to the breaker, the quick solution is to get access to the back of the panel and verify the terminals are tight. If so find out what is actually on the CB circuit and insure it does not equal or exceed the breaker capacity. If it does exceed the capacity (which I doubt) then something must be removed from the circuit and placed on another circuit with sufficient capacity or a new unused breaker. This is also something the new friend (step two) needs to check, but before he has had those beers.

Yankee802
10-31-2008, 10:30 PM
You make an excelent point Jon, and I'm trying to bribe my nephew to come down here for a (cough) vacation. :) While he is here, he can bring his broken laptop and I'll fix it, and of course while I'm busy doing that, why doesn't he have a peek at a few things....THEN we can have beers!

Geoff

garyde
10-31-2008, 10:44 PM
There is no way there should be 3 heaters on one 20 amp circuit. The wiring is not capable of handling the load let alone the circuit breaker. Geoff, verify what the wattage of each heater is first. It sounds like a heater has been added sometime after the original conversion, or the heaters have been upgraded and exceed the original wiring capability.

Yankee802
10-31-2008, 10:49 PM
Gary,

I'm thinking you are right, and that the heater in the basement is an add-on. It does not have a electrial plug, it's hard wired. So it's my plan for now to get something to read the temprature of the basement remotely and only run that heater when it's freezing outside and only as long as I need it. I can either use my furnace and/or not run one of the inside heaters untill the basement warms up to prevent freezing. The two inside the coach I'm positive are originial from the converter and seem to be operating perfectly. From what I can tell, each one seems to be drawing about 14amps, and when the two inside ones are one, it's showing 28 amps.

Jon Wehrenberg
11-01-2008, 04:30 PM
Of all the heaters, the one in the basement (I'm assuming water compartment, if it is in another bay this post does not count) is most likely to be for freeze protection and that one is likely to have a separate breaker labeled bay heater or something like that.

On both my buses, one close in age to Geoff's I had toes space heaters all of which had dedicated breakers.

Yankee802
11-02-2008, 12:05 AM
Unfortunatley all the heaters are on the same breaker. You are correct Jon, the one in the basement is in the water tank bay to keep them from freezing. I have popped the breaker on and off, for each in turn, and they are all on the same one. :(

Jon Wehrenberg
11-02-2008, 07:23 AM
Geoff,

That makes no sense. I don't doubt what you are saying, but from a design point of view and from a safety point of view that is just wrong.

Get more beer for your electrical guy and see if he can change that.

First, determine if the wiring to the heaters is done via "homeruns". The electrical guy will know what that means. If so, and if you have space for more breakers then you can put a heater on its own individual breaker.

If the heaters are "loop fed" getting them on dedicated breakers will not be as easy, but it is so important I would recommend they be rewired to have each heater on its own circuit. It is not easy running new wires in a converted coach, but it can be done and it needs to be done. Maybe Gary can jump in here with some suggestions. I just find it weird that all of your heaters are on a single circuit breaker. BTW, do not even consider increasing the breaker size so it does not trip. That would be a dangerous thing to do and could result in a fire.

garyde
11-02-2008, 08:03 PM
I think the first thing is to find out what is the wattage of each heater .
If each heater is only 500 watts or 750 watts, there would be less concern. If the heaters are 1500 watts each, that is too muh for one 20 amp circuit breaker. Some heaters are designed to change the wattage output and /or voltage input, You should verify this as well.

jello_jeep
11-02-2008, 10:19 PM
You might look here too for more insight into toe kicks..

Jon and Gary are right on about the power.

JJ

http://forum.prevostownersgroup.com/showthread.php?t=1549