A7 AirTap install (ASHP hot water heater) - Page 34

brogsie · 10-01-13, 10:16 AM

Quote:

Originally Posted by Xringer

Those 'extra wires' were discussed back a few pages..

Thanks Xringer,
I did see that but was unsure how to hook the black wire up and weather the built in t stat needed to be disconnected.
I should unplug the connectors on the built in thermostat then hook black wires up to the tank t stat?

I'm a neighbor Xringer. Live in Bedford work in Lexington.

Xringer · 10-01-13, 10:23 AM

Dude! I'm on my way out right now. Going to Bedford on the bikeway and having lunch at Sun Valley and a brownie at the Depot.. Will reply when I get back..

brogsie · 10-01-13, 10:35 AM

Be careful at Sun Valley that they don't bite ya. I get coffee there sometimes. Not the friendliest gals.

Xringer · 10-01-13, 01:13 PM

Pepper and egg was today's special..

My wife gets the food, while I perform bike security.

I'll message you my phone number and we can chat, or I can hunt-n-peck a while here..

Xringer · 10-01-13, 03:02 PM

Seems like there are ways to by-pass the onboard shorted T-Stat on a new A7.

If it shorts,(runs all the time) and has two black wires hanging out the back,
you can disconnect one of the wires into the on-board T-Stat,
and use a T-Stat that's built into your hotwater tank.

Those two black wires would be connected to the unused 240vac (high current) T-Stat.
If you ever need to do this, message me, and I'll supply the details.

It looks like brogsie's hotwater storage tank has a low voltage T-Stat,
so it might not work so well, handling the power used by the A7.

Brogsie's superstor storage tank is connected to his hotwater boiler.

It's got a water-to-water HX inside, that is driven by a circulator pump.

Since that Pump isn't doing anything right now, it can be disconnected.
That pump power should be usable to power the A7.
(Need to add one 120vac metal outlet box and socket.. $5?)

But, depending on the relay, it might be marginal.
My Oil burner water pump relay box (Type R845A) is rated for 120vac
at 7.4 Amps full load & 44.4 Amps locked rotor. (label inside box lid).

The A7 sucks down about 8A, so it's close, but should work okay.
Especially, if the relay is only used once or twice a day.

ctgottapee · 10-01-13, 08:45 PM

A while back someone mentioned running the A7 refrigerant copper feed line in through the bottom port of the tank...

I'm wondering how well this would work.
The action of running it from the top spirals down from the bottom, but pushing it in from the side at the bottom of the tank would force the lead bit to 'run' around the tank - maybe not so good for the tank lining - and lacking some control, much different than the top approach.

I'm lacking room and suitable mounting on top of my marathon tank....

NiHaoMike · 10-01-13, 09:30 PM

If the thermostat can't handle the current, use it to switch a contactor. Really oversize the contactor (like using a 30A) and it would last a long time.

Xringer · 10-01-13, 09:35 PM

Not sure how the loop comes to rest when it's pushed down from the top..
It could be a nice spiral, like shown in their drawing, or just a mess of loops.

If you were feeding it in from the side, you could put a slight curve into the copper.
(Use a 5gal bucket as a bending form. Don't kink)!

By holding the curve (semi-hook) horizontal, it should curve around, along the wall.
Making nice on-the-wall loops..

If the loops are on the bottom, it might work better, since the warm water will head upwards.

ctgottapee · 10-02-13, 01:06 AM

Quote:

Originally Posted by Xringer

Not sure how the loop comes to rest when it's pushed down from the top..
It could be a nice spiral, like shown in their drawing, or just a mess of loops.

If you were feeding it in from the side, you could put a slight curve into the copper.
(Use a 5gal bucket as a bending form. Don't kink)!

By holding the curve (semi-hook) horizontal, it should curve around, along the wall.
Making nice on-the-wall loops..

If the loops are on the bottom, it might work better, since the warm water will head upwards.

Do you see what I mean though by the different process??

Coming from the top, it is like pushing a straightened slinky in. The tip doesn't spiral around the tank linking, it just acts as an anchor on the bottom for resistance. The copper doesn't touch the tank until it hits bottom.

Coming from the side, the tip actually has to travel the wall, which seems like it could damage it, and there is quite a bit of coil to travel, probably 4 to 5 laps around. You are not pushing a slinky in, you are winding the coil laps around the tank. It also seems like some blind luck is in order, or maybe removing the lower thermostat to help guide it/watch progress.
I can only imagine the resistance would scary to get it started....

After a loop or two, I imagine the resistance of the coil winding against the side might get tough. I don't think you could pre-bend it accept for the initial head as you would need a straight on lead to put enough pressure on as you feed it in to keep it running - remember it is not like the slinky approach where you are stacking it.

I was thinking maybe I could lube it up with a water soluble edible product, after my dad mentioned it was like giving a water heater a colonoscopy lol.

It's possible from the top you don't get it all at the bottom, however there is no reason it shouldn't slide down if you keep the pressure you need on it; but from the bottom, you can't control it either, after one loop around the tank it starts going up on its own, but not likely an issue.

Hopefully the prior posting is monitoring and can report more on his technique

Xringer · 10-02-13, 07:06 AM

If it balls up into a small bundle or is a bunch of large loops.
I don't think it's going to make two BTUs worth of difference.

It's soft flexible copper, if it is able to damage the interior Porcelain coating of the tank, I would be very surprised.

10-01-13, 10:23 AM	#332
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Dude! I'm on my way out right now. Going to Bedford on the bikeway and having lunch at Sun Valley and a brownie at the Depot.. Will reply when I get back.. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

10-01-13, 01:13 PM	#334
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Pepper and egg was today's special.. My wife gets the food, while I perform bike security. I'll message you my phone number and we can chat, or I can hunt-n-peck a while here.. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

10-01-13, 03:02 PM	#335
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	The Last AirTapper Seems like there are ways to by-pass the onboard shorted T-Stat on a new A7. If it shorts,(runs all the time) and has two black wires hanging out the back, you can disconnect one of the wires into the on-board T-Stat, and use a T-Stat that's built into your hotwater tank. Those two black wires would be connected to the unused 240vac (high current) T-Stat. If you ever need to do this, message me, and I'll supply the details. It looks like brogsie's hotwater storage tank has a low voltage T-Stat, so it might not work so well, handling the power used by the A7. Brogsie's superstor storage tank is connected to his hotwater boiler. It's got a water-to-water HX inside, that is driven by a circulator pump. Since that Pump isn't doing anything right now, it can be disconnected. That pump power should be usable to power the A7. (Need to add one 120vac metal outlet box and socket.. $5?) But, depending on the relay, it might be marginal. My Oil burner water pump relay box (Type R845A) is rated for 120vac at 7.4 Amps full load & 44.4 Amps locked rotor. (label inside box lid). The A7 sucks down about 8A, so it's close, but should work okay. Especially, if the relay is only used once or twice a day. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less.. Last edited by Xringer; 10-01-13 at 03:08 PM..

10-01-13, 09:30 PM	#337
NiHaoMike Supreme EcoRenovator Join Date: Oct 2008 Location: Austin, TX Posts: 1,154 Thanks: 14 Thanked 257 Times in 241 Posts	If the thermostat can't handle the current, use it to switch a contactor. Really oversize the contactor (like using a 30A) and it would last a long time. __________________ To my surprise, shortly after Naomi Wu gave me a bit of fame for making good use of solar power, Allie Moore got really jealous of her...

10-01-13, 09:35 PM	#338
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Not sure how the loop comes to rest when it's pushed down from the top.. It could be a nice spiral, like shown in their drawing, or just a mess of loops. If you were feeding it in from the side, you could put a slight curve into the copper. (Use a 5gal bucket as a bending form. Don't kink)! By holding the curve (semi-hook) horizontal, it should curve around, along the wall. Making nice on-the-wall loops.. If the loops are on the bottom, it might work better, since the warm water will head upwards. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

10-01-13, 10:35 AM	#333
brogsie Helper EcoRenovator Join Date: Oct 2013 Location: mass Posts: 51 Thanks: 26 Thanked 3 Times in 2 Posts	Be careful at Sun Valley that they don't bite ya. I get coffee there sometimes. Not the friendliest gals.

10-01-13, 08:45 PM	#336
ctgottapee Helper EcoRenovator Join Date: May 2013 Location: Central IL Posts: 97 Thanks: 34 Thanked 9 Times in 8 Posts	A while back someone mentioned running the A7 refrigerant copper feed line in through the bottom port of the tank... I'm wondering how well this would work. The action of running it from the top spirals down from the bottom, but pushing it in from the side at the bottom of the tank would force the lead bit to 'run' around the tank - maybe not so good for the tank lining - and lacking some control, much different than the top approach. I'm lacking room and suitable mounting on top of my marathon tank....

10-02-13, 07:06 AM	#340
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	If it balls up into a small bundle or is a bunch of large loops. I don't think it's going to make two BTUs worth of difference. It's soft flexible copper, if it is able to damage the interior Porcelain coating of the tank, I would be very surprised. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..