Let's talk Heat Pumps??

[Ford truck guy]

I am new to heat pumps and have a question... This past weekend it was a wee bit chilly so I hit the heat pump on... My theromastat has the following settings:~~ cool-auto-on-gas heat-electric heat...I placed it on electric,,the trailer heated up very quickly BUT..... I felt hot air coming from BOTH the AC ducts , and the floor registers ?? Is this normal?? I am not complaining , as it heated up very nicely !!

[atom ant]

Thats normal - but seems weird I know.

If you are trying to heat up beyond about 5 degrees (difference between actual temp and desired temp), the thermostat is designed to bypass the heat pump and kick on the furnace. You most likely set the thermostat to heat up a trailer that was more than 5 degrees colder than the setting - hence the furnace.

Because the heat pump fan is tied directly to the thermostat, you get that too, even though the heat pump compressor did not start. Once the furnace heats up the trailer and shuts down, everything will go back to normal using the heat pump, if you are still in the "electric heat" position.

The feature is kind of a safety, so that when the heat pumps cant keep up, the emergency backup is the furnace. To avoid the heat pump fan from coming on, you would have to heat the trailer using the furnace only for a large delta in temp, then switch over to electric heat. Otherwise, what you did and what it did is normal and it all works out in the end.

[RWJSIM2003]

The Heat Pumps are great. We hardly used the furnace during the winter our HP worked all the way down to about 35 Deg's after that we had to use the furnace.

[Ian Smith]

Set the heat pump temperature to just 3 or 4 degrees above room temp, as soon as the heat pump starts set the thermostat to your desired temperature. This means no running back and forth to set the temperature and gas furnace will not start.

[travelin' texans]

Mine the HP puts out heat & furnace will run at the same time if you set the tstat above 5 degrees ambient. It's fantastic to take the chill off quickly!

[atom ant]

Originally Posted by travelin' texans

Mine the HP puts out heat & furnace will run at the same time if you set the tstat above 5 degrees ambient. It's fantastic to take the chill off quickly!

I wonder if my heat pump was also putting out heat while the furnace was running and I didn't notice it was heat. I thought just the fan was running.

[atom ant]

Originally Posted by Ian Smith

Set the heat pump temperature to just 3 or 4 degrees above room temp, as soon as the heat pump starts set the thermostat to your desired temperature. This means no running back and forth to set the temperature and gas furnace will not start.

I tried that on mine, and even if the heat pump is running, if I push the thermostat too far above actual temp the furnace starts anyway.

However, the front heat pump has no tie in to the furnace, so I think it will run at any delta in temp.

[travelin' texans]

Your front could actually be blowing cold air while the furnace is trying to warm it up. So do you monitor the temp so you can shut off the front when too cold? I only have one HP.

[atom ant]

Many many many times I have woke up to both units running furiously, one on heat, and the other on AC. Because they are not integrated, and because Dory is a lizard and requires continuous heat to live, we find that if we are not careful we leave them both on in opposite modes.

I'm not sure if that was what you were asking or if you were asking someone else -sorry Danny.

[travelin' texans]

You got it. Did that more than once! Also in previous SOB running the fireplace & ac. Duh!!

[RifRaff]

Hey read up on Heat Pumps, don't plan on using below 44 degrees below this it may very well run until heat pump burns up.

[rob_fla]

Originally Posted by RifRaff

Hey read up on Heat Pumps, don't plan on using below 44 degrees below this it may very well run until heat pump burns up.

Todays RV Heat Pumps are really no different than a S&B Heat Pump, once you get to the 40 Degree area they get very inefficient and will not heat.

A S&B Heat Pump will switch to Emergency Heat (Electric Heat Strips) when it gets too cold outside and they will not produce heat where as a RV Heat Pump will switch to Gas Heat if they cannot keep up with the demand due to the outside air being too cold.

That is why S&B Heat Pumps are typically only found in the South, they only work during a mild winter, during the colder Northern winters they do would work vey good at all.

[atom ant]

Our S&B is a hybrid - heat pump with gas furnace backup. Now that gas prices returned to being competitive with electric, we shut the heat pump down and just run gas in the winter.

[Ford truck guy]

I did not have the other t-stat on..mi am sure of it... It makes sense as my wife set the t-stat with the HP on it for like 74-75 and the the temps inside were at 62/63... Makes perfect sense now.. Thanks for all the replies