My rinnai heater won't shut offf at the set temp. The built in Thermostat reads 10 degrees cooler than the actual room temperature. Any ideas?
Also, can an external thermostat be installed to be able to put a programmable thermostat on the unit?
Behind the unit near the floor level, is a yellow wire with a black bulb at the end. This is the actual sensor for returning air. If there is cool air infiltrating the area where it is located, it will keep the unit running until the return air reaches temperature. You could also have a bad sensor but highly unlikely. Make sure there is no air infiltration influencing the sensor. Also, you can unclip the sensor and pull out a few more inches of wire to locate it higher up away from the floor. Tie it up with a wire tie.
Rinnai it testing a remote thermostat but as of yet, there is no plans to offer one.
What if the black bulb is missing
×
The temp sensor on all Rinnai heaters are a yellow wire with a black bulb at the end of it. It measures the air behind the unit flowing through it. It is coiled up so that if necessary, it can be relocated outside of the chassis. This is a common problem with poor insulation in walls or poor installation. If the vent kit isn't sealed properly, cold air from the outside will cool the air behind the unit. Try moving the sensor to just outside the unit through the grates on the side, or make sure the vent kit is installed properly. It is a varible resistor, and VERY rarely fails. No, an external thermostat can't be installed since it measure resistance, and doesn't use a normal 24volt system to switch the heater on and off. If you could find a way to hook an external thermostat to the unit, you would undo what makes this unit so great. Self modulating heat control allows for more accurate temp control, and energy savings. The last thing you want is this unit turning on and off at high fire only.
Cutting power to this unit is single-handedly THE WORST thing you can do for it. If you do this, you are stopping the heater from cooling itself down with it's circulation fan after the call for heat is complete. This WILL cause premature failure of the heat exchanger. Things are meant to be heated and cooled with the controller built into the unit. If Rinnai thought it was OK to put a thermostat on...they would have external thermostat connections. This unit carries a 10 year warranty on the heat exchanger because it has a computer inside to monitor the temperature and protect it. Altering this will be an easy way to void this warranty, and kill the unit.
If you fire up your heater and let it warm up, then turn the POWER button on the unit off..you'll notice the fan continues to run even though the display is not on anymore. They did this for a reason...
P.S. Cutting and altering the length of the wire will effect the unit. Since it is a Thermister (a temperature sensor that varies resistance with temp change) adding wire to the system increases the resistance in the circuit. Every inch of wire carries a pre-defined amount of resistance. Therefore, (hypothetical numbers), if 80 degrees were to be 1.2 ohms, adding additional resistance would alter the reading of the unit. IF you increased that to 1.3 ohms, the unit would think it was 78 degrees.
The thermistor runs (at around room temperature) between 10k and 100kOhms. I add about 6' of 16 gauge wire to relocate the thermistor where it would sense room temperature rather than floor temperature. The 6' or so of wire adds, maybe, a few milli-Ohms of resistance and varies insignificantly with temperature at room temp. The "fix" works fine but I would not recommend unless comfortable with electronics (likely voids warranty too but I'll take that over too hot or too cold and the unit running too hard). TRL - ASEE/BSEE
×
Definitely the thermostat location. My Rinnai is located right next to the entrance door of my house in the Adirondack mountains. Even when the house is at 70 degrees, the heater reads 62. The thermostat bulb is located in the rear of the bottom right corner of the heater, near the floor. (I have an unheated crawl space) This is probably the coldest spot in the house. Simply relocating the bulb solved the problem.... Simple and easy.. Hope this helps...
How did you get the chasise off??
×
The location of the sensor needs to be higher but my yellow wire would only pull out a couple of inches.
Turn off power to unit and remove front panel. Two screws near top/sides. Top of panel pulls out (unplug wire connector to indicator lights) and lifts off bottom tangs. Now you will see a coil of yellow wire inside unit. Remove the wire tie and you'll have enough yellow wire to locate the sensor well above the heater.
I think and will test later.... YES....
Its seem that its just like my pellet stove.
take a low voltage thermostat you STILL need the THERMISTOR the little black bulb/senser at end of yellow wire....
wire it as follows.....
Thermostat wall mounted
you have 2 wires coming from that let's say red and black for this talk.
red wire runs from wall mounted thermostat to back of heater
black wire runs from wall mounted thermostat to one side of yellow wire then other side of yellow wire to back of heater basiclly put the THERMISTOR inline.
Set thermostat.... to temp... you will most likey get and error or blinking light while the thermostat is NOT calling for heat. Once the thermostat calls for heat the error should clear and heat should come on.
Set the temp in the 1004F for highest setting.... I'm not going to be able to test for a few days but I think this should work.... let me know if you beat me to it...
Had just purchased and installed the 1004FA to my garage which we are in the middle of converting to a play room. I must say that the unit operates fine with the exception that the unit registers ~ 7 deg lower that the actual room temp. I then came to a solution of moving the thermistor... cut and stripped the yellow wire and respliced the thermister to about 8 feet away on the same wall. Now the unit opererates fine and shuts down when the set temp is met. It was easy since the walls are open and wiring is hidden.
Tried to connect a programmable thermostat but its a no go. The heater does not like when the thermister is in an open condition and the main readout on the units control bourd blinks that there is a problem with the thermister. I'd like Rinnai to come out with an adapter for the unit to operate on a programable thermostat it would be a huge plus.
Make sure there is no cold air at the location of sensor. My unit is located on a out side wall and under the floor is not insulated therefor the unit runs until the floor is up to temp. This unis works fantastic but should be able to adapt nto a wall thermostat.
Check out the LUX PSP300 outlet programmable thermostat. This thermostat is plugged into the electric outlet, and the Rinnai is then plugged into the thermostat.The LUX is a full featured thermostat that includes an adjustment of +/= 5degrees F for its base temp reading.It controls the appliance by cutting power. When the Rinnai 1004 powers back up after power interuption it will be set at its default temp setting of 70 degrees F. For most applications this works great as the location of the temp sensor on the Rinnai means you should not need a setting above 70 degrees F.I purchased mine from efi.org for $45.00. Hope this helps......
15,718 views
Usually answered in minutes!
I have the exact same problem with my 1004. Some days it will read 54 degrees in on the unit and its 65 in the house. I also have 431 in the same house with out the issue. my dealer said an add on thermostat, hard wire to the unit would solve the problem,,, it this true ?
Won't sut off. question if need a remote trermostat
I have the same problem, temp on thermostat reads 7-10 degrees coolerthan room temperature. I think thermistor should be monted higher in unit. It is basically mounted on the floor, which would be a cold area. Otherwise I love this heater, it is very efficient.
Whe I try to set the temperature above 66 degrees it gives a code of AOS
my Rinnai 1001f won't shut off once room temp is met. Please advise.
I don't get any error code(s) but my Rinnai EX22CP was installed right beside my basement door, leaving the thermistor that senses the temperature near floor level and a small cold air leak. The installer said they could not install a thermostat elsewhere in the room (checked...Rinnai does not make one or allow for such). Finally having had it with the unit running too much when set to 62 deg.s, or not enough set at "Low", I read the install manual online and decided to relocate the thermistor (yellow twin lead wire to black thermistor) that sat near floor level at the back, left, of the unit. Although some have cautioned against "fooling with it", by cutting it off, leaving wire on each end to separate and strip (about 3/4"), splicing in a 6' twin lead 16 gauge lamp cord and relocating the thermistor away from the floor and cold air, the unit runs fine now. It runs less often, less "hard" and maintains an even temperature. Its setting does not match the thermometer near where I set the thermistor. If I set the unit to 66 deg.s, the room temp reads 68. Close enough for me. NOTE: I would not recommend this "Fix" to anyone who is not comfortable with electronics. I have quite a bit of electronics experience and read the install manual regarding the thermistor circuitry 1st! The thermistor's resistance should read between 10k and 100k Ohms. The lead I added reads in the milli-Ohms, insignificant change to the sensing circuitry. Too bad Rinnai can't just make a kit to extend the wiring and/or a thermostat to work with their units.
Thank you! I am somewhat handy with circuit boards and diagrams. I have a FC824 and think this might be the same problem. I set it for 68, it reads 60-66 most of the time and heats the sunroom to 80 degrees. I suspect it is a draft from the sunroom windows (it is 25 outside right now). I will look at the unit and see if this same solution is practical for me.
Thank you! I am somewhat handy with circuit boards and diagrams. I have a FC824 and think this might be the same problem. I set it for 68, it reads 60-66 most of the time and heats the sunroom to 80 degrees. I suspect it is a draft from the sunroom windows (it is 25 outside right now). I will look at the unit and see if this same solution is practical for me.
×