Heat Pump Questions

[jmihalko]

I have a 15'x30'x48" above ground pool. I recently bought a Hayward HP21104T HeatPro 110k BTU heat pump (I know, overkill, but we may be getting a different pool in the future). I was assured there would be no issues hooking it up to my system. All existing piping is 1.5" and the new heat pump has 2" connections. I just wanted to verify with someone else that putting 1.5"x2" adapters at the entry/exit to the heat pump to connect to my existing system would not cause any issues.

Also, the new heat pump specs list a minimum ampacity of 35a and a max fuse size of 60a. It seems that a lot of people I have read info from are putting these on 60a breakers, but I don't see the need for more than a 40a breaker (running 8 gauge copper). Am I missing something?

Any help would be appreciated.

Additional info:

location - Upstate NY
Hayward single stage 1hp pump
Hayward sand filter
inline chlorinator

- John

[Watermom]

Hi, John. I'm going to let someone else answer your questions about heat pumps. Just wanted to say hello and welcome you to the Pool Forum! Hope you find it helpful!

[PoolDoc]

Call Hayward to be sure, but a 40A circuit would be fine . . . IF you don't have a long run. Actually, what Hayward may be pushing you toward is a 40A breaker, with #6 wire. Wire length from the mains to pool equipment tends to be long, and voltage drops can cause problems. Larger wires avoid the problem.

[BigTallGuy]

I would not put anything bigger than a 40 amp breaker on a circuit with 8 gauge wire.

Specific wire sizes mandate breaker size.

Is this circuit a dedicated circuit meaning the Heat Pump is the only thing on the circuit, or do you have other items running off of it like your pool pump etc.?

How long is the actual circuit from the Service Panel to the unit?

If you have a long run, do like Ben said and go with a #6 wire and a 50 amp breaker.

[PoolDoc]

Sorry -- updated your membership, but didn't move your thread. You have posting access again.

[jmihalko]

Thanks for the info. It is a dedicated run just under 60' which is why I was thinking the 40a/8ga setup would be fine, but I wanted to double check here to make sure I wasn't missing something obvious (or maybe not so obvious :-) ).

Also, does anyone see any issues with the 1.5"x2" adapter on the inlet/outlet for the heat pump? The heat pump has a min/max gpm rating of 35/75 and my current pump is rated @ 90 gpm, but that is an unrestricted rating. By the time the water flows through the hoses and the sand filter to the heat pump it is within the 75 gpm rating and I don't believe running it through the 2" piping in the heat pump should cause it to drop enough to take it below the minimum. Any thoughts? Thanks.

[BigTallGuy]

IMHO I think you're fine. The reducers from 2" to 1 1/2" shouldn't really do anything to harm the Heat Pump, you May slightly reduce the flow and there by reduce the efficency SLIGHTLY, but nothing to worry about. As you stated, you have plenty of overlap on your capacity ratings. The 60' dedicated circuit with 8 gauge wire along with a 40 amp breaker should be no problem.

[BigDave]

Are you planning to plumb the recommended bypass and isolation in 2"? Leave enough pipe length next to your 1.5"x2" reducers to cut them off and add new 2" piping in the future without losing the whole bypass / isolation.

[jmihalko]

Good point. I wasn't thinking of plumbing that in 2" but that would make more sense as I would have more of the system I can re-use on an upgrade. Thanks!

[psciotti]

John - I was looking at this heater myself and my local pool companies want big $$ for it. I was thinking of buying online and have my electrician hookup (I can do the plumbing). Is the electrical hookup as complicated as the wiring diagram shows or is everything prewired inside and you just have to feed it?

Thanks ~ Paul

[jmihalko]

Paul,

The heat pump is all pre-wired so you only need to hook up the 2 hots and the ground to the correct blocks inside the unit. If you look at the diagram it shows 2 line connections, just run your hots to there and hook the ground up to the ground lug. You will also need to get a grounding rod and hook up an external ground from the location on the outside of the unit to the grounding rod.

You should also run the wiring inside of watertight conduit. I ran 8/2 w/ground interior wire to a junction box then #8 thhn from the junction box, thru the watertight conduit to the unit.

Here is a photo of mine after I hooked it up:
http://www.flickr.com.KILLED/photos/81603634@N02/7475318160/in/photostream
https://lh6.googleusercontent.com/-VjQeo73uspM/T-_GzAiCMLI/AAAAAAAADco/nflTzE9qW1I/s800/junction%2520box.jpg


- John

[PoolDoc]

Just a caution . . . none of us can 'sign' off on your installation as being "AOK", just from your description and a picture. That's not a criticism; just an observation and a caution.

Good luck!

[psciotti]

Thanks for your help. I will have my certified electrician do it, I just didn't want to spend good dollars on the unit and then find out some pool installation knowledge was needed (above and beyond the basic plumbing hookups).

Also, did you follow the plumbing diagram shown in the owners manual? It looks like it shows both a Hartford loop and a check valve.... anyone know if I need both? My old unit had check valve in internal plumbing and no Hartford loop so I'm not sure. BTW - I do not have a chemical feeder...use BBB method!

page 10: http://ak.poolsupplyworld.com/wpdf/hp21104t_install.pdf

Thanks ~ Paul

[PoolDoc]

Well, they called it a Hartford loop, but it's not one. It's become common to call any sort of U-shaped piping arrangement near a piece of equipment a "Hartford loop", I guess because they can't think of anything else to call it. (I'm a Master Plumber, so I'm not just saying that.)

What they are try to do is create a point where any gases from a inline chlorinator won't flow back to the heat pump. It's not necessary to have one, unless you have an inline chlorinator. Even if you do, if you install the check valve as show, it's not necessary to have 2 U's, one point up, and one point down. You just need the check valve on the left leg of the upside down U.

They do show the heat pump on a bypass loop. I'd seen this thread, and decided to stay out of it, because I'm so far behind. But, if I were doing it, I'd maintain continuous 2" piping, and put the heat pump on a 1.5" bypass.

Do NOT use Chinese made ball valves for your piping -- I've gotten burnt badly over the past few years using Chinese made stuff from Lowes, even when it was American branded!. The Hayward pool valves are OK. I think these valves are OK:

King Brothers WLT-1500-S 1-1/2-Inch Slip PVC S-40 Commercial Ball Valve, White (http://www.amazon.com/exec/obidos/ASIN/B000K1BDDM/poolbooks)
King Brothers WLT-2000-S 2-Inch Slip PVC S-40 Commercial Ball Valve, White (http://www.amazon.com/exec/obidos/ASIN/B000K1DI7G/poolbooks)

Industrial grade valves from Hayward or Spears are fine. One caution though: to winterize a ball valve you MUST put the valve handle at a 45, neither open or closed fully. Otherwise, you trap water in the valve body.

[BigDave]

...You will also need to get a grounding rod and hook up an external ground from the location on the outside of the unit to the grounding rod...Check you local electrical code. Driven rod may be OK in some places not in others. That lug should probably be connected to your pool's bonding grid. Your electrician should know - ask him/her.

[psciotti]

As always - thank you for all the expert advice and the time spent giving it!