Would like to raise the temp sensor up off the very cold floor so that the heater will not run as much. It keeps the space warmer than needed when nobody is home. Is there a kit available to do this?

Go to home depot and get a wireless switch thats rated for the heater and plug it into the heater- I'm afraid moving the sensor may not have the lasting effect you are looking for, as for heat rises so the ceiling is the opposite of where you want it the floor would be absolute best and closest to the garage door. Is your garage insulated? if so try and move the sensor to the most draftiest spot. DO NOT COVER the thermostat sensor because this will trap the heat and cold and you would get really annoyed quick with the lack of control. Good luck
https://www.6ya.com/mr.mike I would like to apologize you are right I had what you wanted backwards, And the unit is used for a garage but in your situation a bit different and I totally understand. I think the first thing I would look at is even getting a cheap thermostat to control it- theres a few ways this can be done but not the most simple. I did not expect a response otherwise I may have asked more question for more accurate advice. Are you technically inclined?
You can make it happen if so. Most people who use those are in clod places and are more actively in their garage but I TOTALLY understand your needs. Im here if you need me.

It could be that you have a bad ETC sensor, but these cars can and do have problems getting air out of them, keep burping the system, if there's a lot of air in it, you'll see bubbles coming up as the car is running. and yes, you could very well have a leak and not be able to see it and it won't leak on the ground just when your driving and the engine is hot....I just went through this same thing with my sons 1989 Supra.

According to the owners manual, the "Economy" mode is designed to reduce the temperature setting by 2 degrees every hour. May not be what you were expecting... On the too hot issue: Check the thermostat setting - it can read either Celsius or Farenheit - Make sure you are setting it to what you think you are... Recommendation: if it is heating higher than set temperature is 1) set the temp lower and see how it does or 2) call a repair man to check and calibrate the thermostat.

You will need to rent or buy a space heater, gas or propane that puts out enough BTU's for the size room you are heating and just run it to keep the room up to temp. for as long as it takes.

Could be a faulty thermostat or a faulty temp sensor.
As long as the computer sees the engine temp is cold it will restrict power to protect the engine.
You would need to know if the engine is getting up to normal temp.
The engine can be "cold" and still produce some heat thru the heater.

Possible heater core poss. thermostat ck. both heater hoses at fire wall 1 hot 1 cold its the core ck pass side floor wet its the core Maybe head gasket

I have a 92/3.8 that did the same thing. This sounds silly but it worked. I used a floor jack and raised the front of the car as high as I could. Then filled the radiator (car NOT running). Hope this helps

Where is the room sensor? High on the wall will be warmer than close to the floor.

Tom

69,000 btuh is adequate for a 12-1400 square foot house.
Otherwise, your thermostat simply tells the furnace to cycle on/off.
If it calls for heat and does not come on, the problem is with switches and relays within the furnace.
Your setting the temp higher only causes the other parts to keep trying until they finally light and heat.
This is based on your information saying it will cycle on and blow cool air--not hot air.
You will have several temperature variations from floor to ceiling.
You probably have ceiling vents as well.
You need a technician to verify the rollout switches, fan relay, inducer fan etc. if the furnace is not firing everytime you call for heat.

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.