Houghton 9.6K AC Temp Mod

[DWM3]

Now that we have some experience with the Houghton 9.5K air conditioner I want to share a mod that makes it work properly (at least what I consider properly). Without this mod the AC would only cool the trailer by about 10 degrees Fahrenheit. It would also constantly cycle on and off, about 4 minutes on and 4 minutes off.

The solution was to move the temperature sensing bulb outside the plenum. After this was done the AC does not constantly cycle and the interior temp drops by 20 degrees. We have only used it in 90 degree weather, so I'm not sure how well it will cool above that, but I expect it will do fine. Temp of the output air is around 50 degrees.

The sensor is mounted inside the unit and is zip-tied in two spots, that when clipped give you plenty of wire to relocate the sensor. Below are photos of the original location inside the plenum and the relocated sensor. It's not too noticeable and vastly improves the performance. I have no idea why it was located inside the plenum because it can't sense room temp in there.

Obviously if you choose to make this mod I can't vouch for how it will affect the unit long-term, but for me the original performance was not acceptable.

[cpaharley2008]

Is the Houghton model an option, I do not like the 11,000 stock BTU's and would prefer a smaller unit.

[DWM3]

No, not an option through Escape. There were supply issues with the Coleman when our trailer was being built and the Dometic is way too loud, so we opted to pass on the AC. Houghton ACs can be purchased from RecPro.com. They have several models. The one we chose was the smallest and seems to be in high demand as it frequently goes out of stock. The 9.5K unit is rated for 400 square feet, which seemed more that adequate to me. I installed it myself with a bit of help from my wife.

[ocala guy]

Thanks again for your help. RecPro answer for an issue you discribe is : I have just installed a ac2800 low profile. The compressor runs for 2 to 3 minutes then cycles off and then back on again in another 2 to 3 minutes. What causes this.
It may be due to a leaking seal. Check the seals both inside and out, as a poor seal can lead to the compressor cycling off.

By RecPro STAFF on July 16, 2021

[meekhotglass]

Appreciate the tip! Got my Houghton 9.5K unit already and have the 21NE coming in October. Keep the updates coming.

[mfschu]

Thanks Don! Glad it works! We have the 13.5 Houghton in our 21NE and are very happy with it so far. I read in the manual that we need something like 18" clearance to cabinets to prevent short cycling. There is only about 6" to my refrigerator so I closed and taped off that supply vent closest to the frig. I think it helps, other wise the incoming cold air gets drawn back into the center return air where the temperture sensor is. If I can figure out how to post a picture I will do so.
Matt

[mfschu]

[Jill]

Originally Posted by DWM3

Now that we have some experience with the Houghton 9.5K air conditioner I want to share a mod that makes it work properly (at least what I consider properly). Without this mod the AC would only cool the trailer by about 10 degrees Fahrenheit. It would also constantly cycle on and off, about 4 minutes on and 4 minutes off.

The solution was to move the temperature sensing bulb outside the plenum. After this was done the AC does not constantly cycle and the interior temp drops by 20 degrees. We have only used it in 90 degree weather, so I'm not sure how well it will cool above that, but I expect it will do fine. Temp of the output air is around 50 degrees.

The sensor is mounted inside the unit and is zip-tied in two spots, that when clipped give you plenty of wire to relocate the sensor. Below are photos of the original location inside the plenum and the relocated sensor. It's not too noticeable and vastly improves the performance. I have no idea why it was located inside the plenum because it can't sense room temp in there.

Obviously if you choose to make this mod I can't vouch for how it will affect the unit long-term, but for me the original performance was not acceptable.

We are trying your mod and have clipped the two zip ties but are not getting any more wire. Did you have to remove anything beside the plenum in order to access the extra wire? I know it has been. While since you did this. And possibly the design has changed some. There is a thin wire that’s in a housing. Did you extend both the housing and the actual sensor wire?

[Jill]

Originally Posted by Jill

We are trying your mod and have clipped the two zip ties but are not getting any more wire. Did you have to remove anything beside the plenum in order to access the extra wire? I know it has been. While since you did this. And possibly the design has changed some. There is a thin wire that’s in a housing. Did you extend both the housing and the actual sensor wire?

Oh I just figured it out. You moved it to come out the opposite side of where the final zip tie was. Duh! We will try that.

[hugh]

FWIW, I actually did the same mod on my factory installed Coleman Mach 10 NDQ. In heat mode, the fan turns off when the setpoint is reached. As the sensor is in the plenum, the temperature would swing about 10 degrees between on and off cycles. Pulling it out of the plenum and into the cabin space fixed the problem.

[Jill]

Just wanted to follow up that we completed the mod and it has made a huge difference. We actually left the sensor detached but inside the housing close to the intake air. The first time the AC ran for 30 minutes without cycling. So I adjusted the set temperature to near room temp to be sure the sensor knew to turn off and it did. We went from being disappointed in the Houghton to so happy with it.

[Ooshkaboo]

On a Coleman 13.5 this will serve as an extra pair of hands and prevent pull on the circuit board wires while doing any maintenance.

[hrewer]

Has anyone done this mod with the 13.5 3400 model? We’re having a hard time finding the sensor.

[JeffinBC]

Originally Posted by hugh

FWIW, I actually did the same mod on my factory installed Coleman Mach 10 NDQ. In heat mode, the fan turns off when the setpoint is reached. As the sensor is in the plenum, the temperature would swing about 10 degrees between on and off cycles. Pulling it out of the plenum and into the cabin space fixed the problem.

Hi. Interested in this but can’t find a write-up. Any tips?

[Ryanb-72]

Originally Posted by hrewer

Has anyone done this mod with the 13.5 3400 model? We’re having a hard time finding the sensor.

Any luck finding the sensor? I was planning on doing the same just haven't taken it apart yet.

[Ryanb-72]

Originally Posted by hrewer

Has anyone done this mod with the 13.5 3400 model? We’re having a hard time finding the sensor.

Yesterday I had a couple of hours to take apart the AC unit to look for the sensor on our 3400 Houghton. I was able to find it inside the return air plenum. I will try and post the picture of where I found it.

I decided to try the easier alternative from mfschu first to see if it would help solve the problem.

I used AC Duct tape on the inside of the vent housing to seal off the two side vents. It was easy to do and took very little time and leaves no visual evidence of modification.

After reinstalling the housing I turned the unit on and it stayed on until the inside of the unit was 70 degrees. It took about an hour to reach that temperature. It was 101 outside in the sun although the trailer was in the shade.

I would call this a huge success and took very little time to complete the modification. So a big thanks to mfschu for the easy but effective mod!!

Ryan

[hugh]

Originally Posted by JeffinBC

Hi. Interested in this but can’t find a write-up. Any tips?

No write-up, but super easy, and takes about five minutes.

Just remove the air inlet grill and filter on the "passenger side" of the AC unit. You'll see a black wire leading to a small metal temperature sensor, attached to the AC unit frame with a single screw.

Just remove that single screw, and let the temperature sensor and wire hang down. Reinstall the filter and you're done.

[mfschu]

Thank you Ryanb-72 for your improvement on the 3400. I completed it as you described and like the air distribution much better as well. Now the air only goes to the front and back of the trailer where it's needed, and not blowing on the kitchen & refrigerator. It seals up much better to put the tape on the side, and looks much better as well. Thanks

[Ryanb-72]

Originally Posted by mfschu

Thank you Ryanb-72 for your improvement on the 3400. I completed it as you described and like the air distribution much better as well. Now the air only goes to the front and back of the trailer where it's needed, and not blowing on the kitchen & refrigerator. It seals up much better to put the tape on the side, and looks much better as well. Thanks

Hopefully it helps with air distribution. Eventually it seems the air in the cabin will even out for a more comfortable experience. Before the air in the sleeping area would not get very cool due to the short cycling. We have added a fan to help but I think keeping the unit from turning off and on so frequently will be a huge plus.