HVAC Advice

[tom slick]

My house has a 3.5 ton Day and Night heat pump with electric aux heat. The condenser/compressor was made in 1994 (10 seer) and the air handler/evaporator is from 1980. The system functions fine currently but I know it is near the end of it's anticipated life.
I have propane and am considering a hybrid system. We have quite a few mornings in the low 30's and summers are in the 90's. In the winter the heat pump runs 8-12 hours a day with 2 of those in aux heat. In the summer the AC will run 3-4 hours. I'd like to cut my electric bill down but only if it makes sense.

Any advice on a replacement? I've had York and Carrier equipment previously. A Lennox dealer is coming out next week for a quote.

 

[rshaw125]

The condenser could easily last another 15 years. Maybe. I have a rental unit with the condenser that will be 40 years old next year. Had a few capacitors and contactors.
When it dies I'm ready. But it won't be replaced until then.

 

[SrDriver]

Check out the Energy Star programs offered by your electric company and the state.

Many electric companies will do a free energy audit not only about your HAVC needs but too what can be done by doing other things around your home that will reduce your energy costs.

Sounds like with your needs an Energy Star heat pump would meet your needs quite well.

This time of year there are often some good buys which could save you some cash replacing the system.

Where people get into higher costs with a heat pump is that they jack up the thermostat in the morning and kick in those heat strips.

Heat pumps often produce a COP of 3.5 - 4.0 or in other words you are getting heat at a greatly reduced cost unless the strips kick in.

The electric provider can recommend some folks for a replacement of the old equipment.

 

[toneydoc]

You may look into solar powered heat pumps. You get plenty of sun in CA. The cost may be higher initially but you may get some tax breaks along with cheaper utility bills

 

[friendly_jacek]

Originally Posted By: rshaw125
The condenser could easily last another 15 years. Maybe.


I went through that decision process a couple of years ago. When slow evaporator leak was found, I did some research and concluded that new equipment with imported parts is nor as reliable as old one made in USA. I invested in a can of leak sealer and everything is fine over 2 years later. My system is Lennox x2 circa 1996.

 

[friendly_jacek]

Originally Posted By: SrDriver

Where people get into higher costs with a heat pump is that they jack up the thermostat in the morning and kick in those heat strips.

Heat pumps often produce a COP of 3.5 - 4.0 or in other words you are getting heat at a greatly reduced cost unless the strips kick in.


Good point. I discovered it myself and disabled the heat strips. No more high bills in cold months.

 

[callbay]

We also heat with heat pumps and I almost switched to LP gas as backup instead of electric backup. This site will help you decide. Turns out in my area LP gas is the most expensive heat even more than plane old electric heat with no heat pump. Many people think LP is almost as cheap as natural gas and much better than heat pumps but not accoring to this comparison site.

http://www.warmair.com/html/fuel_cost_comparisons.htm

 

[azjake]

York and Carrier are good brands and so is Trane. However 6 years ago we replaced our old A/C and gas furnace with a 4 ton 13 seer Rheem heat pump (lowest price) and have been very happy with it. We're in the Phoenix area so we can experience 110+ in summer and a few winter nights in the upper 20s and have never had any problems with the Rheem. We get a once a year checkup on it in the spring and that's about it.

 

[Propflux01]

WE have temps in the low 20's in winter, but my heating strips have never come on. I am wondering if your heat pump is not going into defrost mode and thats whats reducing your heating output?

 

[tom slick]

From what I've read some heat pumps can operate below freezing. Mine does not so the heat strips turn on and the compressor turns off when it gets near freezing.

Last month my average kwh was $0.22. Base rate is about $0.11 but we were into the third tier, which is about $0.36/kwh.

Propane is 2.85/gal

According to warmair.com it would cost the same to use propane or electricity to heat the house. I'm planning on staying with a heat pump system but am interested in using propane as the aux heat.

 

[friendly_jacek]

Originally Posted By: Tim H.
WE have temps in the low 20's in winter, but my heating strips have never come on.


How do know that? I discovered it only when noticing the air from the registers was warmer than I thought it would be by measuring delta.

 

[Propflux01]

Well, when I manually engage them, the whole house lighting dims. Then house smells like burning dust (not "burning electrical") for a few seconds, telling me there is some dust on them. If they are kicking on automatically, I'm not seeing the dimming or smelling the funk. It's only happening when I manually do it once a month. I figure if they were kicking on, I would know it by the dimming, and by my electric bill.

 

[friendly_jacek]

I see. Mine were programmed to come in frequently, for example when defrosting coils and some more.

 

[Propflux01]

And that could very well be happening, but just saying if it is, I'm not seeing it.

 

[azjake]

Originally Posted By: tom slick
From what I've read some heat pumps can operate below freezing. Mine does not so the heat strips turn on and the compressor turns off when it gets near freezing.

Last month my average kwh was $0.22. Base rate is about $0.11 but we were into the third tier, which is about $0.36/kwh.

Propane is 2.85/gal

According to warmair.com it would cost the same to use propane or electricity to heat the house. I'm planning on staying with a heat pump system but am interested in using propane as the aux heat.


Although it doesn't get below freezing that much here in Phoenix, my heat pump which does NOT have heat strips has operated fine on the few winter mornings it's got into the upper 20s.

 

[tom slick]

I had a Lennox dealer come out today and found out he is my neighbor a couple of doors down. We discussed heat pump, hybrid, and furnace systems. According to him, in our area, a propane furnace is more economical than a heat pump and he was surprised we had a heat pump. He told me the only heat pumps he sees are on vacation homes that don't have propane service.

It'll be interesting to see the quote for new equipment.

 

[JHZR2]

Watch these HVAC guys. Some of them pad their rates so severely that it is insane.

 

[sleddriver]

Originally Posted By: tom slick
My house has a 3.5 ton Day and Night heat pump with electric aux heat. The condenser/compressor was made in 1994 (10 seer) and the air handler/evaporator is from 1980. The system functions fine currently but I know it is near the end of it's anticipated life.
I have propane and am considering a hybrid system. We have quite a few mornings in the low 30's and summers are in the 90's. In the winter the heat pump runs 8-12 hours a day with 2 of those in aux heat. In the summer the AC will run 3-4 hours. I'd like to cut my electric bill down but only if it makes sense.

Any advice on a replacement? I've had York and Carrier equipment previously. A Lennox dealer is coming out next week for a quote.


I have a 22yr old heat pump with strip heat backup. Currently working fine. Scary what new is going for. $3000/ton in some cases? That's nuts. . .

Realize a new system isn't going to correct any airflow problems or hot/cold room issues. That fault lies with the duct system, including the returns.

Also depending on your age, you'll have a hard time recouping any benefit from a higher SEER unit, unless your climate is rather extreme. One guy has told me that all the units now are basically the same, as they have to meet a certain standard.

I'd buy depending on the company who'll be servicing the unit, cleaning it on a regular basis, their level of customer service, etc. I'd research THEM as well as the equipment itself.

Also check to be sure they'll do a Man. J (load calculation) on your home instead of 'guessing' the size. That'll answer the question "How much heating/cooling do I really need?" Bigger costs more to operate and doesn't really mean better performance, depending on your climate.

My quick story: I designed and installed a new duct system in my 30 yr old house year before last. The old ductwork was WAY too restrictive, including the return air. After crunching the numbers, turns out I was paying to run a 3 ton AC, but only getting 1.8 tons of cooling out of it!

You don't want to make that mistake. Now that I have a proper duct system, it's amazing how much cold air it delivers when it's 105° outside. Same old 22 yr old unit. It was the ductwork that was strangling it.

 

[Thermo1223]

If you are going to replace now the main thing to look into is a dual stage HP, that way it operates almost continuously on lower 1st stage keeping you warm/cool and saving money. Only kicking to high when needed.

Also do not use a programmable thermostat. That is keep the temp the same night & day. Heat pumps do not recover as quickly as fossil fuel units. You could easily cause the strips to come on and burn through electricity.