Heat Pump question...

[clemsonfor]

What is home warranty? It sounds like a homeowners association for appliances :confused2:

If you buy a house you can buy a warrenty for like 1 3 or 5 years. Unless you buy an older house with old systems and your not very handy there not a very good deal. Im thinking for my house when i bought it a few years ago it was going to be several thousand dollars. I tried to tell them that they would need to do better as i have all new applicances that i bought with the loan for the house as well as 2 new heat pumps. One old one remained but they way we have it worked we dont even use it and havent for 3.5 years. They said oh it covers everthing including your coffemaker and i think TV and water heater. The kicker is that there is like a $100 fee for calling them out. So your not gonna call on anything worth less than $100 ie coffe maker toaster etc. And if my older water heater goes out im going to replace it myself so it will only cost me a few hundred more than the call plus i did not have to pay out the huge lump sum ( and all my other major appliances were under manufacturer warrenty anyway). If the roof had minor leaks i would fix them to for minor cash. They really dont make sense like i said if you do your own work and you ahve new systems in the house. Again if your handy a leaky toilet is no big deal usually $20 in parts fixes it, but if you had to call a plumber the warrenty may be not so bad?

 

[Larry Caldwell]

In process, I've got a home warranty, so I must use them...

David

Well, if you have a warranty you did the right thing - wait until it breaks completely and let them replace it. If you actually owned it, you might have saved some money by calling for service before it died completely.

They tell me heat pumps rely on the skills of the installer. I firmly believe mine has been running trouble free for 17 years because I got bids, then went with the guy who impressed me as knowing what he was doing. He wasn't the low bid, but was reasonable, and did more work than the other contractors were proposing.

 

[LD1]

Im thinking it should be 7-10 degrees warmer than the room air if its funtucioning correctly.

It should be much more than that, especially this time of year.

@ 30-40 outside, mine is 20-25 degrees warmer.

Down about 17-20 degrees outside, the air comming out is only about 10-11 degrees warmer. And any less than that, propane becomes more efficcent. If only 10degree warmer air is coming out, I can see the thing having to run non-stop and not make much headway

 

[grsthegreat]

It should be much more than that, especially this time of year.

@ 30-40 outside, mine is 20-25 degrees warmer.

Down about 17-20 degrees outside, the air comming out is only about 10-11 degrees warmer. And any less than that, propane becomes more efficcent. If only 10degree warmer air is coming out, I can see the thing having to run non-stop and not make much headway

A heat pump doesnt pump out hot air, it just graually warms the indoor air up a little at a time till its at the set point.

 

[LD1]

A heat pump doesnt pump out hot air, it just graually warms the indoor air up a little at a time till its at the set point.

It should still pump out well more than a 7-10 degree increase:confused2:

7-10 degrees is VERY poor when outside temps are above 30

My unit manages a 15 degree rise down to the low twenties ambient temp.
And is closer to 30-35 when outside temps are 40+.

At only a 7 degree temp rise on a 40+ day, something is very wrong. I'd almost wager a bet that resistance heat would give you more BTU's in the house for a less wattage draw

 

[grsthegreat]

It should still pump out well more than a 7-10 degree increase:confused2:

7-10 degrees is VERY poor when outside temps are above 30

My unit manages a 15 degree rise down to the low twenties ambient temp.
And is closer to 30-35 when outside temps are 40+.

At only a 7 degree temp rise on a 40+ day, something is very wrong. I'd almost wager a bet that resistance heat would give you more BTU's in the house for a less wattage draw

the differential will vary depending on how cold it is outdoors. On a colder day it will be less than a warmer day. Not sure what the actual differentials will be, but will NOT feel like hot air blowing out of the ducts.

 

[Ford850]

It should still pump out well more than a 7-10 degree increase:confused2:

7-10 degrees is VERY poor when outside temps are above 30

My unit manages a 15 degree rise down to the low twenties ambient temp.
And is closer to 30-35 when outside temps are 40+.

At only a 7 degree temp rise on a 40+ day, something is very wrong. I'd almost wager a bet that resistance heat would give you more BTU's in the house for a less wattage draw

I just checked mine. It's low 40's outside. Checking a vent within 3' of the furnace it is 13 degrees above the room air, but 15 above the basement air temp. Since it pulls from the basement some too I'll just say it was 15 degrees above air temp. The air feels very warm to me. I can't imagine it blowing air 35 degrees above room air temperature. That must feel like a blast furnace when it kicks on. That seems like it would be inefficient since it would be kicking on and then off so soon.

 

[LD1]

the differential will vary depending on how cold it is outdoors. On a colder day it will be less than a warmer day. Not sure what the actual differentials will be, but will NOT feel like hot air blowing out of the ducts.

I know all this. That is EXACTALLY why I gave outdoor temps as well. And what it "should be" at those temps.

I just checked mine. It's low 40's outside. Checking a vent within 3' of the furnace it is 13 degrees above the room air, but 15 above the basement air temp. Since it pulls from the basement some too I'll just say it was 15 degrees above air temp. The air feels very warm to me. I can't imagine it blowing air 35 degrees above room air temperature. That must feel like a blast furnace when it kicks on. That seems like it would be inefficient since it would be kicking on and then off so soon.

Checking it as soon as, or close to as soon as it kicks on isnt accurate.

It takes it a few minutes to get everything warmed up. All that cold duct-work and all. But on an average 40's day outside, my return air is 68-70 degrees, and I am getting upper 80's to lower 90's comming out.

Lower twenties outside, same room temps, and I get lower 80's air comming out.

I had another thread last year and I am not trying to hi-jack this one, But I have been monitering my system for over a year now. Knowing the CFM of the blower, and temp rise, it is very easy to figure your BTU output. And easy to compare that to the wattage used by the heating system.:thumbsup:

And some hard #'s for ya. My HP draws 12 amps. I have a 1000CFM blower. That equates to 10900BTU/hr if the heat rise is only 10 degrees.

That same 12A if were used as resistive heat would have produced 9800BTU. So a 10 degree temp rise on my system only equates to 1.1x's more eff than resistive. And is actually the break even point for my propane B/U.

And even the 90 degree air I get out of my vents doesnt feel "hot". It is just warm. My propane gets 140+ easy.

Again, if you are only seeing 10 degree rises in temps, something is really wrong with the system, or it is really cold outside. Mine isnt even a newer unit. It is 15 years old and a 10seer:confused2:

 

[LD1]

Forgot to mention, something else to check is how hot the copper "in" line is going to your furnace from the outdoor unit. On a 40 degree day, the freon going into the furnace is 130-140 degrees.:thumbsup:

 

[techman]

First of all, based on the most recent post you may have an issue. Have a pro look at it.

You should invest in a GOOD programmable thermostat. The upper end Honeywell units (IAQ, 8000) have "intelligent recovery". With this, when you set back, it will bring it the temp without the electric backup heat, and learn the time it takes to do it. It will then start the recovery early to meet your temp at the programmed time. You can also add an external temp sensor and use that to lock out the backup when you are above a preset temp outside.

paul