New air handler/furnace/gas

[tim5055]

Well, some of you have followed my house moves and upgrades for the past few years. It is now time to begin getting the house in the mountains of North Carolina ready for full time occupancy.

The house is about 10 years old and according to my HVAC guy there he thinks the equipment is a little older. The previous owner/builder was in the construction industry and I have already found bits/pieces he "acquired" from various job sites to build the house. But, I digress from the questions....

Currently the compressor/heat pump is on the west side of the house where we intend to build a deck/outdoor living space, so it's gotta move to the east side. The air handler is in the crawl space and has electric emergency heat strips.

My plan is to move the existing compressor/heat pump to the east side of the house. The air handler would be changed out for a new unit with LP Gas emergency heat. Right now even though the only gas appliance in the house is a set of gas logs, they installed CSST from the west side of the house all the way to the east side. The previous owner said he had thought about a LP gas generator (the meter/main/electrical panels are on the east side) and wanted to be ready. The CSST is broken up into about four lengths, apparently they purchased pre-made up lengths and cobbled them together. There is no evidence of any bonding on the CSST. The only bond is from the gas regulator on the west wall of the house to the ground wire in the HVAC disconnect.

The new air handler would have a variable speed fan and be comparable with both new/old refrigerant, but as I will use the existing compressor for a while it will initially be set up with old.

I would have all CSST replaced with black iron and the gas plumber said he would drive a new/additional ground rod for the installation. While he is under the house I'm going to have him stub a pipe under the kitchen island for a future gas cook-top.

OK experts - what am I overlooking????

[Marc]

Dang smart of you to insist on replacing those left-over scrap pieces of CSST (that's what I suspect it is) with good-old solid iron.

When the HVAC contractor brings in the indoor section with the gas backup, look at the label on the coil cabinet and make sure it indicates dual compatibility with R-22 and R 410A. I've seen many HVAC guys claim such compatibility but the label says in unmistakable terms NOT to use any refrig other than R-410A. The label should not be violated.

I hope the schrader valves on the outdoor section hold when your HVAC guy transfers all refrig to it (for the move). Your existing gas, R-22, is selling at prices so high that the loss of such gas might well mean that you've not saved a single penny by keeping the old outdoor section. Same thing if a leak develops after the move.

If you can get the serial number/brand of the outdoor section, anyone here can tell you the manufacturer date. That's important to know. I mean, who knows what else this contractor/builder has done.

Forget the extra ground rod. That's for distant equipment like swimming pool equip, etc.

Are you sure that variable speed blower will work in conjunction with a constant speed compressor?

Marc

[tim5055]

Dang smart of you to insist on replacing those left-over scrap pieces of CSST (that's what I suspect it is) with good-old solid iron.

When the HVAC contractor brings in the indoor section with the gas backup, look at the label on the coil cabinet and make sure it indicates dual compatibility with R-22 and R 410A. I've seen many HVAC guys claim such compatibility but the label says in unmistakable terms NOT to use any refrig other than R-410A. The label should not be violated.

I hope the schrader valves on the outdoor section hold when your HVAC guy transfers all refrig to it (for the move). Your existing gas, R-22, is selling at prices so high that the loss of such gas might well mean that you've not saved a single penny by keeping the old outdoor section. Same thing if a leak develops after the move.

If you can get the serial number/brand of the outdoor section, anyone here can tell you the manufacturer date. That's important to know. I mean, who knows what else this contractor/builder has done.

Forget the extra ground rod. That's for distant equipment like swimming pool equip, etc.

Are you sure that variable speed blower will work in conjunction with a constant speed compressor?

Marc

The HVAC guy is a square shooter. He says the existing compressor, but I will ask to be sure. I'll also ask about just changing the compressor. With a new air handler and line set it will be the only "old" equipment.

On the ground rod, when the compressor goes away the disconnect the gas regulator is grounded to will go away also. Won't I need a ground?

[Trent Tarter]

You might want to consider updating the whole HVAC system. Some of the newer inverter/variable speed heat pumps are very efficient and are heating all the way down to around 9 degrees with heat pump only. Lennox makes one of the most efficient air source heat pumps called the XP 25, it's also solar ready and has a 23.5 Seer Rating.

[Jim Katen]

Personally, I'd add a conventional LP water heater along with an LP cook stove. That way, when the power goes out, you can take a shower and cook. Generators are a pain in the butt and they never seem to work when you need them.

[Marc]

The HVAC guy is a square shooter. He says the existing compressor, but I will ask to be sure. I'll also ask about just changing the compressor. With a new air handler and line set it will be the only "old" equipment.

On the ground rod, when the compressor goes away the disconnect the gas regulator is grounded to will go away also. Won't I need a ground?

You do not want to replace the compressor alone. Any expense that large should get you R-410A compatibility. If, for any reason, it turns out that you need to replace the compressor, replace the entire outdoor section instead. R-22 prices are not going down, only up. Last time I bought a 30# R-22, it was about 4 times the price of R-410A and that was over a year ago.

I'm not sure about a ground for the gas pressure regulator. That's a fuzzy area for me.

Trent offers sound advice, especially if that R-22 system is actually much older than the builder/seller is saying. You could just leave the system as is until you're ready to upgrade it.

Marc

[kurt]

I'm with Trent. Why wouldn't you just upgrade the whole shebangabang? Seems silly to salvage a few parts and then dink around with them.

I look at a lot of generators. They work great. The #1 cause of malfunction is folks don't change the battery every few years, like on a car. It's an internal combustion engine with a starter....it needs a good battery.

[tim5055]

You might want to consider updating the whole HVAC system. Some of the newer inverter/variable speed heat pumps are very efficient and are heating all the way down to around 9 degrees with heat pump only. Lennox makes one of the most efficient air source heat pumps called the XP 25, it's also solar ready and has a 23.5 Seer Rating.

Good points. I will look into them

[tim5055]

Personally, I'd add a conventional LP water heater along with an LP cook stove. That way, when the power goes out, you can take a shower and cook. Generators are a pain in the butt and they never seem to work when you need them.

Thanks. Both are on the table. While the guy is doing the black pipe work I am already having him stub the pipe in the island for the cooktop. The new cooktop will wait until the Corian is removed and we go to granite.

The water heater is also on the table and a stub out will be placed for that. I'm just wondering conventional tank or on demand heater.

[tim5055]

I'm with Trent. Why wouldn't you just upgrade the whole shebangabang? Seems silly to salvage a few parts and then dink around with them.

I look at a lot of generators. They work great. The #1 cause of malfunction is folks don't change the battery every few years, like on a car. It's an internal combustion engine with a starter....it needs a good battery.

I already have this that will move with me:

http://www.northerntool.com/shop/tools/ ... swod-MEGbA

The house has a manual transfer switch already, all I need to add is the receptacle to plug it in on the outside wall.

[kurt]

OK, I thought you were talking about a Generac stationary system. Those portable jobs are awesome; personally, I think you're set on the generator part.

Conventional tank vs. on demand...... How far from the fixtures is the water heater going to be and do you have a return loop for the hot water?

[tim5055]

OK, I thought you were talking about a Generac stationary system. Those portable jobs are awesome; personally, I think you're set on the generator part.

Conventional tank vs. on demand...... How far from the fixtures is the water heater going to be and do you have a return loop for the hot water?

the master bath is on the other side of the wall from the existing WH, kitchen maybe 20 feet from the WH and a guest bath on the other side of the house. No return loops, but I could probably add them.

[kurt]

The on demand thing can go either way; some folks love them and others hate them. I was sort edging into the hate end of it....more like exasperated because of how long it took to get hot water to fixtures that were 20-30' from the WH.

You might want one of these....because of this.....or maybe not.

Especially interesting is this (cut and pasted from Green Building Advisor) ......."even as the flow rates of faucets and showerheads has dropped, plumbing codes are increasingly mandating larger-diameter piping, so the wait times for hot water have increased, a fact that's exacerbated by the larger houses we're building. In addition to the long wait for hot water, all of the cooled-off water sitting in the pipe goes down the drain. Nationally, there?s a huge amount of water wasted in this way."

The Watts system takes up the slack of standby loss, which may or may not be a consideration for you. Depends on your personal water use ethic.

There's also something called the "cold water sandwich"....when you're in the kitchen turning the water on and off constantly, it "confuses" the sensors and you can hit a spot where you don't get hot water until the system resets.

I hated my on demand heater. I changed back to conventional. I never found it to have an appreciable effect on my water bill. I'd also consider one of the newer high btu output jobs...they're 25 gallon tanks but very quick recovery.

I was an early adopter though. Maybe the on demand types have gotten better. 10 years ago, they were just a pain in the ass.

[Jim Katen]

I'm just wondering conventional tank or on demand heater.

Will an on-demand unit work without power?

[tim5055]

I'm just wondering conventional tank or on demand heater.

Will an on-demand unit work without power?

Probably not, but will any of the newer tanks? I thought they had all transitioned from a pilot light to a piezo igniter??

[Nolan Kienitz]

You might want one of these....because of this.....or maybe not.

I've been using one of those Watts recirculating pumps on my 50-gallon W/H and it has been flawless. 6-10 minute wait for hot water disappeared at the two bathrooms on the far side of the house from the W/H in the garage/closet.

I also just replaced my A.O. Smith Vertex W/H with a standard A.O. Smith 50-gallon unit. The Vertex was only 8 years old and was massive loud with snap/crackle/pop and I had been cleaning/draining tank each year. Then the electronics unit started going wonky. I had to cycle power off/on to get it back to run. Found that cost for that controller and such was almost the cost of a new heater.

So ... new heater is now in place.

[Jim Katen]

I'm just wondering conventional tank or on demand heater.

Will an on-demand unit work without power?

Probably not, but will any of the newer tanks? I thought they had all transitioned from a pilot light to a piezo igniter??

Nope. Old fashioned pilot light.

[kurt]

I've been using one of those Watts recirculating pumps on my 50-gallon W/H and it has been flawless. 6-10 minute wait for hot water disappeared at the two bathrooms on the far side of the house from the W/H in the garage/closet.

Good to know.

[Tom Raymond]

I would advise against a watts system if your house is new enough to have a potable water sprinkler system. Domestic water temps can be very close to sprinkler head activation temps.

[kurt]

never heard that one before. How'd that work?

[Jim Katen]

I would advise against a watts system if your house is new enough to have a potable water sprinkler system. Domestic water temps can be very close to sprinkler head activation temps.

How would the potable hot water get near the sprinkler heads?

[Marc]

As I understand it, one of the resid sprinkler designs available integrates sprinkler water with fresh water supply and keeps the sprinkler heads near the path to plumbing devices to minimize the chance of stagnant water. If the Watt's return path is near a sprinkler head, it could affect it. The concept is there but I wonder if it's practical for that to happen.

Marc

[Jim Katen]

As I understand it, one of the resid sprinkler designs available integrates sprinkler water with fresh water supply and keeps the sprinkler heads near the path to plumbing devices to minimize the chance of stagnant water. If the Watt's return path is near a sprinkler head, it could affect it. The concept is there but I wonder if it's practical for that to happen.

Marc

But the hot water is in its own pipes and in a dedicated return pipe. How would the hot water get into the cold water pipes?

[kurt]

Right. The fancy valve that's installed at the fixture is temp sensitive; once the water gets to the set point (usually around 98F), it closes so the cold water supply doesn't get hot.

At least, that's what the marketing and sales reps told me.

[Marc]

Wait a minute now..is the Watt's return circuit a dedicated line like Jim K said, or is it a cold water supply line?

And is that 98 degrees not high enough to wreck havoc with the sprinkler head?

Marc