ASHP question

[Xringer]

Originally Posted by poleikleng

Xringer,

Thanks for the information. Downstair we have 1060 square feet, we do not heat the upstairs. I'm of the opinion the heat pump fan runs at a constant speed when the temperature drops (if my memory serves me well?). I will have to confirm this. Again, thanks for all your help, I really appreicate it.

Poleikleng

It might run constantly, it depends on your heat loss. If you have low loss,
it should to slow down at some point..
As the remote signals a room temp drop, it will increase for a while
and then back off. But it the room temp keeps dropping, it will run
at max constantly, trying to catch up..

I wonder if you should protect your upstairs from freezing, by leaving
the upstairs unit set for 60F, (or at minimum setting) a few hours before the temp drop is going to hit.?.


As it starts getting really cold, I think we might try lowering the settings to 18C/64F, so the units don't have to work as hard..
And move the setpoints of the back-ups lower too..

[poleikleng]

Originally Posted by Xringer

I've been thinking, Maybe running two units will make enough heat to
keep the oil burned from turning on.. Wishful thinking maybe?


My other idea is to plug in a couple of space heaters, and set them to come on at 65F..
While the Sanyos will be set for 19C (66.2F).
At about 4,000 BTUh each, they won't keep the house warm, but they might keep it from getting really cold..

And of course, I could set the oil burner to trigger at 63F !

Xringer,

I will be away from home during this upcoming cold spell and I will have to set the house up for my wife. I'm thinking of setting the oil burner to 62 degrees and running the heat pump downstairs. Last cold spell (13.8 degrees) we did not use the oil furnace. Also, turning on our 1-ton upstairs unit to 60 degrees as you mentioned. I don't like the idea of burning oil but it's better to be safe than sorry.

Poleikleng

Poleikleng

[poleikleng]

Xringer,

Currently it is 41 degrees outside, I have the remote (line-of-sight) set to 68 degrees, one room is 65.5 degrees, the other is 65.8/64.8 (I have two thermostats for this room, don't know why they don't read the same?). Should the rooms be closer to 68 degrees or is the heat pump running within its acceptable range for this heat setting?

Poleikleng

[Xringer]

Originally Posted by poleikleng

Xringer,

Currently it is 41 degrees outside, I have the remote (line-of-sight) set to 68 degrees, one room is 65.5 degrees, the other is 65.8/64.8 (I have two thermostats for this room, don't know why they don't read the same?). Should the rooms be closer to 68 degrees or is the heat pump running within its acceptable range for this heat setting?

Poleikleng

What is the displayed temperature on the remote control??

When I set my living room Sanyo (#1) to 20C (68F), the remote always
displays it staying at 20 to 21C.

BUT, when the sun isn't helping out, the two other sensors in the living room, will always display a lower temperature.
Normally 1 or 2 degrees lower. Since my remote is within line-of-sight (18 feet maybe),
it gets hit by warm air, while other parts of the room are not as warm..


Check out my new weather display..

[poleikleng]

Originally Posted by Xringer

What is the displayed temperature on the remote control??

When I set my living room Sanyo (#1) to 20C (68F), the remote always
displays it staying at 20 to 21C.

BUT, when the sun isn't helping out, the two other sensors in the living room, will always display a lower temperature.
Normally 1 or 2 degrees lower. Since my remote is within line-of-sight (18 feet maybe),
it gets hit by warm air, while other parts of the room are not as warm..


Check out my new weather display..

Xringer,

The remote is set to 68 degrees and is 20.5 feet from this inside air handler.

Currently (3:52 pm) 38.1 degrees outside, inside: one room is 66/65.3 and the other is 65.3. Heat pump was consistant today and I'm happy with the performance. Inside temperature never did reach the 68 degree setting of the remote but 68 degrees is too warm for us.

We too have a radio controlled weather station similar to yours but diffferent brand.

Poleikleng

[Xringer]

When you are having the problem, (too cold) what is does the display
on your remote control show??

On mine, I have to press one of the Hi-Lo keys before it displays the setpoint selected.
But, the default display shows me the air temperature at the remote..

So, to re-word the question:

Is the remote displaying the same temperature as your requested setpoint??
(Assuming the system has been on for a few hours and hasn't been adjusted up or down).

[poleikleng]

Originally Posted by Xringer

When you are having the problem, (too cold) what is does the display
on your remote control show??

On mine, I have to press one of the Hi-Lo keys before it displays the setpoint selected.
But, the default display shows me the air temperature at the remote..

So, to re-word the question:

Is the remote displaying the same temperature as your requested setpoint??
(Assuming the system has been on for a few hours and hasn't been adjusted up or down).

Xringer,

"When you are having the problem, (too cold) what is does the display
on your remote control show??"

76 degrees


"Is the remote displaying the same temperature as your requested setpoint??"

Yes.

On our remote you just press the "Set Temp" button up or down (in 2-degree increments) to select your temperature setting.

Poleikleng

[Xringer]

Sounds like it works like mine, and many wall mounted digital thermostats.

So, if you have the remote set to 68 (set-point), and it also displays 68 degrees air temperature around the remote..

It's working okay! And what you are seeing as a problem is lower readings from other thermometers??

[poleikleng]

Originally Posted by Xringer

Sounds like it works like mine, and many wall mounted digital thermostats.

So, if you have the remote set to 68 (set-point), and it also displays 68 degrees air temperature around the remote..

It's working okay! And what you are seeing as a problem is lower readings from other thermometers??

Xringer,

I do not have a digital thermostat next to the remoter but I will set one up and see what the results are. But, last Saturday when the heat pump was running all day, set to 76 degrees, the inside temperature of the house only got to 63 degrees (you could feel the cold temperature inside the house). Once I turned it off and turned it on again (3:00 pm) you could feel the house getting warmer and indeed the temperaure rose to 67 degrees. We didn't need the thermostat to tell us the house was warmer.

Hopefully I can speak with a Fujitsu tech support person (they were closed today) and ask them what could cause this type of operation. It has happened to us twice and both times turning the heat pump off and turning it on again corrected the problem.

Poleikleng

[Xringer]

I've just been reading your manual. I don't think your remote works like my Sanyo remotes.

http://s3.pexsupply.com/manuals/1298..._PROD_FILE.pdf


I can't find anything to indicate there is a heat sensor inside your remote control..
Nothing about line of sight. It looks like the heat sensor is located in your indoor unit (IDU).

If that is the case, you might have problems with controlling
the temperature in areas that are not near the IDU..

Warm air coming out of the bottom of the IDU, will rise to the ceiling,
where it will be sucked into the air-intake (on top of the IDU).
That warm air will warm up the sensor (located inside the air input)
and decease the speed of the motors (and the heat output)..


The source of hot air, is too close to the built-in sensor, so it's going to
get cold in areas, away from the IDU..

Setting it to 88 and using a fan to blow the warm air where you need it might work..

~~~
Using a build-in sensor is perfect for cooling..
Since warm air is up where it can be pulled into the air-intake.. And cold air stays low..