A Coil Problem

[DUD]

I have a 3 ton AC unit that the inside coil has rusted out the pan and is dripping badly over

the indoor electronics. We have been thinking about a heat pump with extra electric heat

strips. Totally get rid of the natural gas, Our electric rates are the lowest in the state.

Does anyone think this is a good or bad idea? Thanks, Bill

[crokett]

Bill,

I am not an HVAC professional, but I do own a heat pump. Advantages are they are slightly cheaper to operate. Also being electric their costs are more predictable since electric rates are not going to fluctuate as much as fuel prices. Disadvantages are that gas heat is 'warmer' heat if that makes sense. I am not sure how cold it gets where you are. Also, my dad can run his gas heat off his generator since all he needs is electric for the t-stat but on a heat pump you need a whole house generator to get heat in winter if you have no power. My backup/supplemental heat in winter is a woodstove.

[master53yoda]

A heat pump should average about 2.3 cop in your area from the information I could get from the weather service you have a 38 f average Jan temp and 3700 degree day heating load. the cop is compared to electric heating with a an electric furnace being a cop of 1. Heat pumps can exceed a cop of 3 or 300 % efficient as compared to an electric furnace. If you want to know if it will be cheaper then gas take your KW electrical rate and multiply it by 29.3 this gives the cost per therm (100,000 BTUs) for electricity. If the Heat Pump COP is 2.3 divide that cost by the COP and that will be the cost of a therm delivered by the heat pump. if you take the cost of gas per therm and divide it by the efficiency of the furnace it will give you the cost of operating a gas system as compared to a heat pump.

If you chose to go with a heat pump make sure that who ever sizes the system uses Manual J calcs. This is a load calculation system provided by the Air Conditioning Contractors of America. If the contractor won't use it or doesn't know what it is the find someone else. Heat pumps MUST be sized correctly or they have a very short life span. Do not oversize the heat pump. It will cost more to run and will shorten the life span.

[Habe]

Bill
We have had a heat pump for 4 years now. We save a bunch on heating and cooling cost. We have a 13 seer rating and use the puron system. If you go 100% electric on you'r heating check with power co. and see if you get a break on the rate. We do because the heat pump is considered primary heat and furnace is back up.

[DUD]

Thanks to All for the responses, I don't have an estimate yet, so I don't know which

way to go. I know I am not going to spend a lot of money repairing when I can replace

the whole unit for just a little more. I guess LOML won't get new LR furniture this

year. Bill

[pierhogunn]

Dud, I must say, it's good to see you up and about working on projects again... I know this has nothing to do with the topic, but all the same any way

Fujitsu has some neat systems, a split system where you could put each room on it's own themostat... pretty kewl I think

[DUD]

The bid to replace A coil is $875.00, is this too high? Bill

[unclecritic]

My 2 cents

In michigan im not sold on a heat pump systems as the weather gets too cold to fast... Heat pumps have problems with this. Another downside is that the air generally coming out of a register is around 96 or 97 degrees... if you feel the air coming out of the register it actually feels cold even tho its warmer than ambient... but it does heat.

I like the idea of a heat pump with strip heaters as backup in your area. It's quite efficient and some electric companies will change your rate if you tell them you are all electric...

With that said, $875 seems a little pricy to change out a coil but I'm not able to see what is involved with the replacement. A 3 ton coil will go to a customer for about $450 not including labor here. But i am leary to have you spend close to $900 to swap out a coil only to have a domino effect of the electronic taking on water for who knows how long. Soon youll have a circuit board, then a relay or three...

Again, my 2 cents

[DUD]

Thanks for the reply, I am back to the forum again and will just try to be here. Our

weather is better down here than Michiganbut We do have ice storms and such,

I am on the same circuit that the biggest hospital is on, so We have fewer interruptions

than the rest of the city. He is replacing the A coil and case, and making My duct work

better for filter area. The prices that I got for a new heat punp with electric heat strips

was not going to allow LOML to get new LR furniture. You know how it goes, Bill