Community Forums

Renden · 03-02-2011, 08:12 AM

I have the duotherm thermostat in front of MH (5 buttons)

I have 2 Thermopumps 13.5 on the DSDP 2006

No problem heating the unit in the front and in the back

My problem is starting the bedroom AC - at times it works - at times it waits and starts if I put the front thermostat (zone 2) very low - I did look at this small unit in the bedroom and cleaned it

Wonder what the problem is ?

thanks for the help

GaryKD · 03-02-2011, 09:35 AM

Hi Renden,
In all Newmar coaches I've seen, zone 1 is the front and zone 2 is the back bedroom. Can you double check to ensure which zone is operating which HVAC unit?

One needs to have both zones on cool. There can be a significant wait for an HVAC unit to come on (first time). Lastly, the rear bedroom is so small the unit may cycle with short bursts of A/C followed by lengthy periods of no operation.

I ended up moving my rear thermistor to a place that provided a consistent temp control for the rear bedroom.

Renden · 03-02-2011, 11:05 AM

Quote:

Originally Posted by GaryKD

Hi Renden,
In all Newmar coaches I've seen, zone 1 is the front and zone 2 is the back bedroom. Can you double check to ensure which zone is operating which HVAC unit?

One needs to have both zones on cool. There can be a significant wait for an HVAC unit to come on (first time). Lastly, the rear bedroom is so small the unit may cycle with short bursts of A/C followed by lengthy periods of no operation.

I ended up moving my rear thermistor to a place that provided a consistent temp control for the rear bedroom.

Zone 1 is the front HVAC and Zone 2 is the rear (bedroom) - I do understand that it takes some time to turn on the AC but Zone 2 at times does not kick in (bedroom) or just works 1 minute and stops......

Route 66 · 03-02-2011, 11:18 AM

Have you tried resetting the system?

Renden · 03-02-2011, 02:01 PM

Quote:

Originally Posted by Route 66

Have you tried resetting the system?

Route 66
How do you reset the system ? Thanks

GaryKD · 03-02-2011, 04:03 PM

Hi Renden,
The new clue is "just works 1 minute and stops". You may have the same problem I had. Try this:
Set the rear temp really low (like 50 degrees). When the rear A/C comes on, does it stay on? If the answer is yes, then set the temp to where it is what you want. After a while are we back to the 1 minute on and then off routine?

If you answer yes to this scenario, think about installing a new thermistor, in a different location. I installed a new thermistor on the rear heat pump. It is not difficult to do. remove the leads from the current thermistor (at the heat pump) tape them up and set them aside (no need to remove the wires). Run the new thermistor through the return air duct work and a vent in the bedroom. To save you some time, after trying different positions, without success, I did the following.

I wrapped the new thermistor in electrical tape, Then I installed it in a ceiling return air vent. I got the idea from how a window A/C thermistor is positioned in front of the returning air. This works very well. Thermistors are very temp sensitive. Buy placing tape around the thermistor and installing it in the return air duct I seem to have lessened its' sensitivity and placed it where the warmer is suppose to be passing by.

You can also try covering the current thermistor's cover. It should work, but I had no success with this try to fix.

Renden · 03-02-2011, 05:37 PM

[QUOTE=GaryKD;801640]Hi Renden,
The new clue is "just works 1 minute and stops". You may have the same problem I had. Try this:
Set the rear temp really low (like 50 degrees). When the rear A/C comes on, does it stay on? If the answer is yes, then set the temp to where it is what you want. After a while are we back to the 1 minute on and then off routine?

YES

If you answer yes to this scenario, think about installing a new thermistor, in a different location. I installed a new thermistor on the rear heat pump.

Do not have the knowledge to do this

You can also try covering the current thermistor's cover.

Does not work

Will have to find a Shop that does this - Independence RV ??

GaryKD · 03-02-2011, 05:51 PM

Hi Renden,
Independence or North Trail. Both have skilled techs and overall good reputations. I've never been to Independence. If you go to North Trail, let me know in advance. I'll suggest who you should talk to.

A suggestion: Once the tech connects and runs the new thermistor to a return air vent, that is about all you want the tech to do at $100+ per hour. You will need to experiment how much wrapping you want on the thermistor. Before trying the permanent wrapping consider using a temporary wrapping until you get it the way you want it for sensitivity. Always test the thermistor fastened to one of the plastic "rods" that hold the return air vent filter and cover in the plastic fitting.

Because Independence was mentioned, you may be in Florida. If you go to the NKK Florida State rally, I can help you with the placement of the thermistor, after the tech installs the new wire and runs the thermistor to the air return vent. I'll need to have some advance notice.

Route 66 · 03-02-2011, 06:04 PM

Resetting and self diagnosis is easy.

Turn the system off via the black switch on the bottom of the thermostat.

Hold down the Zone and Mode buttons and turn on the system.

Release the 2 buttons and "FF" indicates a successful test and reset.

siggyd · 03-02-2011, 07:57 PM

IMHO Newmar does not place the temperature sensors in the correct place ! They need to be AWAY from the outside walls,like on the INSIDE wall of the bedroom, opposite the closed bath.
Just my common sense opinion.
Siggy

Renden · 03-03-2011, 07:59 AM

Thanks GaryKD and Route 66

Will be driving up I-4 when I leave the West Coast from Clearwater area and Independence RV is closer for me since Ft Myers is 3 hours South of here

I will do the reset today.....

.how about just changing the thermistor which is not on an outside wall in my Bedroom ?

Renden · 03-03-2011, 12:34 PM

Quote:

Originally Posted by Route 66

Resetting and self diagnosis is easy.

Turn the system off via the black switch on the bottom of the thermostat.

Hold down the Zone and Mode buttons and turn on the system.

Release the 2 buttons and "FF" indicates a successful test and reset.

Reset done with success but it does not change my problem - thanks Route 66

GaryKD · 03-03-2011, 12:43 PM

Hi Renden,
I have yet to find a factory installed thermistor I could change the location of. There is no spare wire to work with. Also I have never been able to determine how to pull the thermistor back through the wall, no matter where it is located. I think Newmar must fasten the wire to the inside of something. Anyway, the thermistor is a very sensitive sensor. I do not think it could be pulled back and repositioned without breaking it. Be careful when you work with the new one.