AC and furnace replacement LBI NJ

Dave0176

Pulled a waaaay oversized 100,000 BTU Lennox furnace and three ton condenser. System still ran but the draft inducer was making noise and they wanted a new system. So I did a heat loss and a York 60,000 BTU 80% down flow furnace went in and a York 14 SEER three ton condenser.

Dave0176

JUGHNE

All looking good, neat & tidy.
Curious though, why not a condensing 90 plus furnace for this application?

Dave0176

JUGHNE said:

All looking good, neat & tidy.
Curious though, why not a condensing 90 plus furnace for this application?

Thought about it but I would've had to run the PVC lines through the second floor to the roof. Easier solution was the 80% and hook back into the 4" flue pipe. I gave the option but they didn't like the added cost.

JUGHNE

I have used the existing B vent as a chase for the PVC exhaust and the B vent for combustion air coming down. Somewhat like the triple wall for closed combustion for trailer house furnaces, if you have ever had the experience of those.

I drill a tight hole in the top of the B vent cap and use the rubber flashing for 2" electrical conduit as in overhead electrical service. The B vent cap openings act as the inlet grill for combustion air.

But if the B vent is shared by another appliance, that method above is out the window.

SWEI

Centrotherm makes a listed kit for this as well.

njtommy

Not a fan of the York micro channel coils. I've done way too many under warranty.

Dave0176

njtommy said:

Not a fan of the York micro channel coils. I've done way too many under warranty.

Me neither Tom, these are the new fin in coil YFE LX series condensers York came out with this winter. No micro channel.

njtommy

That's good news Dave. Hopefully they will do the same on their larger tonage equipment and roof top units.

ChrisJ

What are the condensers on these made out of usually, aluminum?

If so, does anyone make a unit with an all copper condenser?

SWEI

Believe it or not, all aluminum coils are starting to look pretty good.

Paul S_3

the carrier & payne condensing units are copper....evaps are aluminum like @SWEI said ive had no issues knock on wood.....ive replaced 6 leaky microchannel condensers with new condensing units this summer. just last week i changed a microchannel reheat coil in a brand new 25 ton rheem.....Evaporator coil in the rheem was copper ,reheat coil was aluminum microchannel dont understand why the manufacture would do that to save a few bucks and have unhappy customers

ChrisJ

SWEI said:

Believe it or not, all aluminum coils are starting to look pretty good.

I'm not believing it.

Though, the condensers I work with are painted steel, I think 18 gauge and the evaporators are SS. They seem to last.

Bob Bona_4

Al coils are preferable to copper bc they resist erosion from the refrigerant oils. That's the word I'm getting.

Dave0176

ChrisJ said:

What are the condensers on these made out of usually, aluminum?

If so, does anyone make a unit with an all copper condenser?

All coils are aluminum finned. York however decided about 6 years ago to go to a technology the automotive industry had used for about the last 17 or so years. The condensers are all aluminum and use flat aluminum bars with very small passages usually about 6 passages. The fins resemble an automotive radiator. The aluminum bars are connected in parallel with a manifold on each end. Unfortunately we've witnessed many leaks at the joints and even in between at the bars. Worse thing is you can no longer pump a condenser down like you can a traditional one, due the smaller size not being able to hold the refrigerant. R134a runs around 180 psi on the high side, were R410a typically runs 300-500 psi on the high side. This was probably the bulk of the initial leaks not being able to withstand the higher pressures of R410a.

This past winter York came out with their 14 SEER YFE LX series of condensers which use traditional copper coil in fin technology. This is a last minute decision because of of all the bad publicly micro channel got. My York representative has told me they did it to gain back their loyal customers, which they'd been losing. However he also told me York has invested heavily in micro channel technology, so it's not going away.

njtommy

I've probably replaced 20-25 micro channel coils most under warranty on all types of equipment ranging from 2 ton split systems to 150 ton air cooled chillers.

Paul S_3

i service about 5 low temp Bohn condensing units with the aluminum microchannel condensers....i guess there coming to commercial refrigeration too

njtommy

@Paul S I've seen them to. I have yet to see any of those leak, but I would assume they may not do to lower head pressures in refrigeration and possibly having a receiver to hold the bulk of the refrigerant in the system and a head master helps too.

On ac units in low ambient conditions the coil will stack up with refrigerant due to not having a receiver. I've seen where the Mirco channel coil will do this and go out on high head. According to York it's due to the oil/ refrigerant restricting the flow through the smaller channels of the coil. So keeping your head pressure up and using a fan speed controller is key.

John Mills_5

Actually years ago York came out with a condenser for use on the coast, called the Survivor. It had an all copper outdoor coil. Bet they sold very few!!! And now there's the Lennox with the all aluminum outdoor coil. Haven't seen that since 1989 when Bryant stopped doing them.

SWEI

http://www.johnsonsupply.com/html/What-Causes-Formicary-Corrosion.pdf

Dave0176

njtommy said:

I've probably replaced 20-25 micro channel coils most under warranty on all types of equipment ranging from 2 ton split systems to 150 ton air cooled chillers.

I agree Tom and the York chillers seem to be a major problem as I've read lots of complaints on that issue.

As for as the rooftops I don't know if their going back to coil in fin, doesn't seem that way right now. It's all still micro channel. I've installed a few York rooftops with micro channel, hoping for the best.

John Mills_5

Actually years ago York came out with a condenser for use on the coast, called the Survivor. It had an all copper outdoor coil. Bet they sold very few!!! And now there's the Lennox with the all aluminum outdoor coil. Haven't seen that since 1989 when Bryant stopped doing them.