Installing a Replacement CO Detector

The CO Detector that came with my Roadtrek had an expiration date printed on the front of it of June 2013. This surprised me as I understood from various research that I did on its replacement that a CO Detector made for an RV should last five years and my Roadtrek now is only two years old. This is a piece of equipment not to be fooled around with so I set out to replace it and install the replacement myself.

The first thing to know when looking for a replacement is that you want the "Surface Mount" model. They also make a model that fits into a hole cut into the wall,but this is not what is used in the Roadtrek. Next - the model number of the CO Detector made by MTI Safe-T-Alert that was in my Roadtrek was model 65-540-WT. I learned from the company's website that the WT is for white as it also comes in cream color and that while this model is still listed on the website's sales page as available the model number that I was finding to match the description of this RV CO Detector was different. The model number was showing up on Amazon and at other sites selling these was MTI Safe-T-Alert 65-541- WT. I called Safe-T-Alert to ask. The 65-540 model is discontinued and the replacement for it is the 65-541. This is an upgraded model with an end of life alarm that will alert you to when it needs to be replaced - in five years. The specs and size of this newer model is exactly the same as the older model. Here is a link to the manual.

Before undertaking this job I wanted to see how this unit was installed. There are two screws holding this to the wooden panel below the rear passenger side cabinet in the Roadtrek. I removed those screws and the unit came down with two wires attached and disappearing into the inside of the unit through a small hole in the upper middle of the back. The black and red wire went into a hole in between two cushioned fabric panels in the Roadtrek.

Here is the unit attached to the bottom of the cabinet. Below it you see the A/C thermostat and temperature controls.

Here is that unit hanging down by the wires.

You will see in the photo that the manufacture date is stamped on the back of the unit. This unit original to my 2011 Roadtrek was manufactured in July 2009 - so, yes, it was five years old and needed to be replaced.

I was hoping that the case of the unit came apart and that inside there were terminals to take off  and reattach the black and red wires. That would have been too easy a design. My thoughts of a quick an easy installation requiring just a screw driver were gone. No, the connections to the 12 volt power source that this CO Detector must be connected to is inside that small parting of the cushions forming that little hole. I looked to see if there was access behind where the wires go and it did not look like there was. I put the screws back in the holes and put the unit back up.



I started asking on the Roadtrek Facebook page and had a quick answer from Jim Hammill, President of Roadtrek, telling me that as my Roadtrek is wired differently from most because a different wiring harness was installed at the factory for my DC/AC refrigerator (instead of the standard propane/DC/AC Roadtrek refrigerator) access was not going to be easy and my choices were removing the floor of the cabinet or just removing some screws to make the opening that the wires pass through temporarily larger by releasing one of the cushioned panels - but I would not be able to access where the actual connections were made. The plan no matter what was to cut the wires on the old unit and splice in the new unit which I will get to as we go along here in this article. Others told me this is how they did the job as well - cut the wires and join the new wires to the old. How different this area in my Roadtrek is from others, I don't know, but others that have done the job tell me that they wound up doing just the same as I will describe to you here that I did.

I ordered the replacement CO Detector from Amazon.com. The price was the lowest that I found - $54.95 plus $7.50 shipping. There was a rebate coupon good until September 2013 that came with the unit to mail in with part of the package to get back $10.  Be aware that I found various prices for this same unit that went from here to over a hundred dollars. Shop around for it. The unit arrived in less than one week. This is what the package looks like removed from the shipping carton. If you look in an RV shop for this, this is what you will see.

I next went shopping for connections. The connections suggested to me were crimp on snap connectors (sometimes called "bullet connectors" and they are available at Radio Shack stores for $2.49 for a pack of ten (five male and five female). They come in red and blue. *Update - Radio Shack Stores have all closed now. You can find bullet connectors in any auto store and you should also find them where electrical connections are sold such as one of the home warehouse stores.

To attach these you need a pair of wiring crimp pliers which cost only a few dollars and I already had a pair. With these you avoid soldering and all you do to attach the wires together with these connectors is push one end into the other and it snaps tightly and stays connected. To disconnect, all you do is pull the connectors apart.

I unscrewed the old unit from the bottom of the cabinet starting to do the installation of the new unit. Someone had said to me that when he did this job he blew the fuse to the CO Detector in the Roadtrek fuse box when he cut the wires and should have removed the fuse first. Good idea so I went to the fuse box to pull the fuse. I quickly found that my fingers would not grab the top of the fuse and Meryl's little fingers were also not getting it out. I knew what I would need - a fuse puller - which is a simple small, tweezer like, plastic device that will not break the fuse but will grab it and pull it out. I did not have one. I thought that I did, but I did not. It was now late in the afternoon with most of the earlier part taken up with the trip to Radio Shack. We locked the Roadtrek and drove to Walmart where the only fuse puller they sold came in an assortment package of fuses. Fine. I bought that and headed home. Now it was getting too late to continue working. No problem. I decided to stop and do this on the next day. I did not want to leave the CO Detector hanging by the wires so I went to put it back up on the ceiling. It was not staying up. One screw was just turning and never tightening. The hole had stripped. Again, not a problem of more than just another delay. I am a old woodworker and to fix a stripped screw hole in wood all you need is a match stick and some wood glue. I patched the hole but the glue needed 24 hours to fully set, so now the next time to continue the job given the time I was stopping would be in two days. Fine. (If this should happen to you - take a wooden match stick and cut off the match end. Cover the wood of the matchstick with wood glue to match the length of the screw that came out so that you have an approximate length of the hole. Don't put so much glue that it will just drip down. Put the matchstick with the glue end into the hole and push up until it stops. Leave it until the glue dries. When the glue is dry cut off the end of the matchstick sticking beyond the surface of the wood.) So I left the CO Detector hanging which turned out to be OK. 

When I finally got back to work on the install two days later the glue was dry. I trimmed the matchstick down and went back to the install. MAKE SURE THE BATTERY SWITCH IS OFF. I pulled the fuse with the fuse puller (so easy). The fuse is labeled on the chart in the fuse box door as CO Detector. I then looked to see where I would cut the wire on the original to get it down. I decided to cut the wire halfway - which I regretted later. I actually should have cut it closer to the unit and left more wire to push back into the hole between the cushions. 

I then cut the wires on the new unit so that there would not be so much wire left over - as any wire coming to the new unit after the snap connectors were not going to fit in the hole between the cushions and even though I was told how to open that hole up more I decided that I wanted the connectors outside of the wall where I could get at them easily if I needed to. I did not want to have to unscrew the bottom panel in the cabinet the next time I would have to change the CO Detector - which is done every five years. To have it so that the connectors would remain easily accessible and outside the small gap between the cushions, I cut the wires on the new unit leaving about 2/3 of the wire on the unit. This too turned out to be too much wire left on (but it is better to have to deal with too much wire than to discover that you cut the wire too short and ruined the new CO Detector. Anyway, the wires were cut on both units and it was time to crimp on the snap connectors. Simply a male connector goes on the red wire attached to the unit and a female connector goes on the red wire attached to the unit.

I put the connectors on the wires attached to the Roadtrek first. This is simple. You strip 3/8" of insulation off the end of the wire and twist the wire strands together so that they stay solidly together. Next push the twisted end of the wire into the snap (bullet) connector as far as it will go and with the crimp tool using the proper crimp size marked on the tool, squeeze the connector around the wire - in two places - near the top of the connector's insulation and also near the bottom. Go around the crimp to get a good seal on the wire. Hold the wire and give a little tug on the connector and make sure the wire stays in the connector. Done. Do this on the Roadtrek's black wire and the red wire. I put a MALE connector on the Roadtrek's RED wire and a FEMALE connector on the Roadtrek's BLACK wire. And then move on to doing the same thing on the wires connected to the CO Detector. MAKE DOUBLE SURE THAT YOU ARE MATCHING MALE TO FEMALE CONNECTORS on the wires or you will be cutting connectors off and starting again. Push and snap all of the connections together and you have wired the new CO Detector in! Simple. And at this point for me it was just that simple. 

The next thing to do is check that it works. Put the fuse back into the fuse box and again using the fuse puller as a fuse pusher this is easy and it will not damage the fuse. Turn on the Roadtrek's battery switch. You will see the CO Detector's green power light start to flash IF IT IS CONNECTED CORRECTLY. If there is no green light on at all you have a problem. Shut off the battery switch immediately and go back and look for what you did wrong. But it should go on if all is well and it does flash for ten minutes which means it is testing its sensors and after ten minutes the green LED on the CO Detector will glow steady green.  Once I saw that all was well and the connections worked, I wrapped each of the joined connectors with electric tape just as an added precaution that they could not pull apart. The CO Detector is there to save your life and you want to be sure these connections are secure.

Now it was time to put the new detector back up on the bottom of the cabinet and screw it in. First, there is now additional wiring to deal with that was not there before and you have wires that need to get tucked behind the detector and wires with connectors between the detector and the wall. Wires on the original between the back of the detector with most going into the hole between the cushions. There was now a lot less wire now to go back into the wall until the connectors stopped the wires from going further and there is more wire to fit between the back of the detector and the cabinet and get the connectors tucked away out of sight. It did not go easily and in the process the same screw hole stripped again - this time more than a quick fix would repair. I decided to use a thicker screw. Since the front hole is out in the open, it is easier to see. The back hole is almost up against the wall and hard to locate from below. Be cautious when dealing with screws in the wood.  With some swearing and time, it all went together and the new CO Detector went snug up to the bottom of the cabinet.

If you want to see what it looks like now, just look at the first photo above of the original CO Detector because it looks exactly the same now. The connectors are tucked neatly against the wall and are not seen unless you look for them and they could be taken down to disconnect should the need ever arise, which will not be until five years from now when the CO Detector needs to be replaced again. This new unit does not have a replace by date on the front but was marked with a manufacture date of March 2013 on the back so in March 2018 an alarm will sound and tell us to replace it. We are putting our own label on the side that says replace in February 2018 so that we will order one and have it as soon as it is needed.  

The new CO Detector is in my Roadtrek and works perfectly!