When to replace HVAC?

[jax1]

How would a homeowner know it is time to replace his HVAC system? I have a 35 yr old forced air ac/gas furnace that service techs say still works well. Is there some way to tell when this system is about to die? Would a newer unit pay for itself in energy savings?

thanks.

[21degrees]

You are on borrowed time, 35 years is pushing it, The pilot light is costing you and afue is probably 50 to 55%. No warranty and reliability. A new furnace will definetly pay for itself. It might take four or five years.

[jax1]

I should have mentioned that I am in Houston, TX. The furnace gets used very little, especially lately with the warm winters. A friend replaced his furnace to the latest and greatest, and he uses $70 a yr. less than me.

I currently use 5000 kwh a year for AC for the 5 month cooling season. What kind of improvement should you expect from a new AC?

My current system has been very reliable so far. Inspections but no repairs. The AC was recharged for the first time 2 yrs ago. Surely there are signs when the system is about to die.
thanks.

[paul42]

It might provide more comfort, it might give you some peace of mind, and it should save you some on your electric bill. But, a new system will not pay for itself.

If the repair bills start going up, or if the cost of electricity doubles, then it is time to replace it.

[firecontrol]

Thing about HVAC equipment is that most times they work till they quit with little warning. Your service tech is the best source of information on replacing it or not due to strictly physical condition and the probability if it's going to have a major breakdown anytime soon.

Replacement of entire systems these days is being driven just as much by the greatly improved comfort that a properly sized and and possibly staged system can give you.

Payback times are calculated first by simply comparing the efficiency differences and doing the math for your area. Anything beyond the obvious comes down to what is your peace of mind and comfort worth.

I realize it's tempting to compare your energy costs with neighbors, but that can be very misleading. When I lived in Florida my neighbor paid easily 6 times as much for energy as we did. Everything was identical down to the ages of our kids. Go figure!

[2old2rock]

Does the system cycle on and off in very warm weather and hold the temp you want? If it is cycling, it can still do the job. If it can't hold the temp you want, and runs constantly, it's undersized, or losing capacity to pump refrigerant.
Could go for many more years. Could die next Tuesday.
Better start a little savings account for a new system.
Although a new system will be more efficient, don't look at it as something you'll make your money back on. It's more a comfort thing.

[smittyii]

i'm bettin it's a g.e. 35 yrs in houston it's got to be. maybe a chrysler airtemp, but i say g.e.

[Freezeking2000]

I should have mentioned that I am in Houston, TX. The furnace gets used very little, especially lately with the warm winters. A friend replaced his furnace to the latest and greatest, and he uses $70 a yr. less than me.

I currently use 5000 kwh a year for AC for the 5 month cooling season. What kind of improvement should you expect from a new AC?

My current system has been very reliable so far. Inspections but no repairs. The AC was recharged for the first time 2 yrs ago. Surely there are signs when the system is about to die.
thanks.

It is time to replace it, you have a leak and a 30 year old system.

[Daltex]

Seems the AC's have a tendency to die on the hottest day of the year. I was hosing off my condenser coils this morning and a head popped up over the fence. It was a HVAC tech working on my neighbors unit. Said I was smart for doing that but as he gazed over my 9 seer array, he gave me his card and said good luck!

If you're ok going without ac for a few days to a week in the hottest part of the summer then wait until it dies. If you can't live without the ac and a hotel is out of the question then be prepaired to someday pay for a costly repair for a unit that will be replaced a few months later.