Question about Rinnai RHFE-431FAIII 16,700 BTU Direct Vent Furnace Energy Saver Heater - Natural Gas

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Rinnai unit I have my rinnai set at 70 and it is reading 74 degrees. If I set it at 68 it will read 78. There is still heat but there still is a problem with the temp. Please help. KS

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Re: rinnai unit

OK, sounds like a sensor problem to me. The temperature reading is done on the backside of this unit. Remove the top cover and with a flashlight in hand, look for a small black rubber probe with yellow wires attached. You will find it about 2 inches above the floor and on the right hand side (when viewing from the front). Make sure this probe is not being influenced by the venting system and showing a “false” reading. If the vent pipe (the one covered by cloth) is close to it, the probe is made that you can relocate it out of the way of the vent. You will need to get to both the backside of the heater and go inside the heater cabinet to do this properly. If the vent is a few inches away and not influencing the probe, place a cold cloth on the probe and see if the temperature drops. Then a warm clothe on it to see if it rises. You could have a bad probe. List your model number and I can get you a part number.

Posted on May 16, 2008

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I just moved into an apartment with a Rinnai energy saver gas heater. It is incremented by 4 degrees...60,64,68,72 etc. 64 is a little too cold and 68 is a little too warm. Do you know of a way I c

Sure, try using a small (desk) fan to move air around the apartment this will allow for more even heating.
hope that fixya up . give me a vote if'n I was of help.I love praise, it's the fuel that keeps me fix'n yer stuff.. Jay


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I have a Rinnai heating system 556F that shut off by itself and the lights start blinking. when I start it again it will start right away but it won't last long till it shut off again (1.5 hours). any...

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AC Thermostat is set to 78 but wont cool past 79 or 80

If your unit is running 24/7 you are either low on charge or the unit is to small for your house.
A 20° temperature difference is about normal for the room air vs the air coming out of the ducts, but the room air and the leaving air should keep getting colder and colder.
An air conditioner should cycle approximately 3 maybe 4 times in an hour if it's properly sized.
As for the thermostat thermometer they are very cheap and are more for reference than actual temperature, so if 78° is not comfortable, then you should set it lower but not rely on thermostat being accurate or what the thermometer is saying as long as it is consistent.
The air conditioner and thermostat can also be set below 78°, there's a lot of people set them at 72° and below with no problems.
the only thing is if you have real low humidity you'll need to watch indoor coil or the suction line (the big line) on your outdoor unit and make sure it doesn't freeze up on you.

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Rinnai 1004 heats to a temp 4 degrees higher than set temp, adjustment?

You can adjust the position of the room air sensor found on the back of the unit between the heater and the wall. It is a black rubber bulb with yellow wires. There is a few inches of extra wire you can extend higher to get a more accurate reading of room air. While you are back there, check for drafts that will give you false readings.

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Rinnai 1004 - Temp on thermostat reads 10 deg cooler than actual, keeps running

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.

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