Replies

1. 
   Bob Dickey|Jul 24, 2016 11:10am|#1

   The heat pump works by taking heat out of the air. As such, the unit acts as an air conditioner. The cooler the surrounding air, the less efficient it will be. Regardless of whether you duct the room like a cold air return or put louvers in a door, you'll probably want to make sure the air in the room is exchanged. I would measure the average temp of the room before the new unit, then measure after installation and use. You can decide on if the temp difference warrants air exchange.
   我自己的一个通用电气GeoSpring,现在有7 +年and the savings for a 3 person family are significant. Mine came with a 1 year parts/labor warranty and a 10 year parts warranty. It has failed twice now, the first time it was some kind of pressure valve, the second it was the compressor. GE has outsourced service to A&E. They were terrible in both cases. They do not carry parts for these units, so the first visit is to assess, the second is to return with the part and fix. In the case of the failed compressor it took 6 weeks and many calls to fix (several mis-diagnosis). Fortunately the unit can be put in "pure electric mode" so I was not without hot water. A&E charges $150 per incident (not per trip) if your labor warranty is expired, no matter how many times they have to show up. I was lucky the first failure was within the 1 year full warranty.
   Having said all this, would I buy another one - yes, in a heartbeat. The savings over the 52 gallon conventional electric heater I had are substantial (in my case). There was not a lot of info (feedback) available when I bought mine, so it was hard to say if it is good or not so good compared to other brands. Mine was made at a time when GE had them build in China (saw it on the box), they are now manufactured in USA.
   One last comment - pay particular attention to the clearances required. Should you ever need service those clearances are required to remove the cover so the electonics/compressor can be accessed.

2. GBA Editor
   Martin Holladay|Jul 25, 2016 06:03am|#2

   Stephen,
   The crucial issue is the room's volume. The manufacturer requires a minimum volume of 700 cubic feet, and the room you are talking about has a volume of only 352 cubic feet. That's only 50% of the required volume -- it isn't even close. So you shouldn't install a heat-pump water heater there. If you do, you'll have no warranty protection, because you will be violating the manufacturer's installation instructions.

   People have tried rigging up holes, ducts, and fans controlled by temperature sensors in an attempt to overcome volume restrictions for mechanical rooms -- but these work-arounds only add mechanical complexity (and opportunities for maintenance problems) to a water heater that is already mechanically complex. I don't recommend these work-arounds.

   For more information, seeHeat-Pump Water Heaters Come of Age.

3. 
   John Semmelhack|Jul 25, 2016 08:59am|#3

   The GE install manual states, "It can be installed in rooms smaller than 10'x10'x7' (700cu.ft.) with the installation of a louvered door or a GE ducting kit....Louvers should have 240 square inches (0.15m2) of open airflow area or greater. If two louvers are used one should be near the top of the door."

   Yes, a transfer grille in the wall meeting the minimum free area would meet the intent of the installation instructions. Most 20x20 return air grilles will have slightly more free area than 240in2...though a pair of 20x10's (one high one low) would yield more air transfer with the open area. You can certainly go larger...the more free area of the louvers, the more airflow you'll get.

   You'll take a hit in terms of recovery speed and efficiency going this route, but in my opinion, if the choice is between a HPWH in a smaller-than-ideal mechanical room (with louvers or ducting) or a standard electric water heater, I'd go with the HPWH.

4. GBA Editor
   Martin Holladay|Jul 25, 2016 09:20am|#4

   John,
   I appreciate your comments. Your answer was more nuanced and technically accurate than mine. Thanks.

5. 
   Andy Kerr|Jul 25, 2016 11:56am|#5

   If you can, consider venting to and from outside by purchasing $205 GE GeoSpring Ducting Kit. Put movable baffles that can be adjusted by season to optimize unit efficiency.

   https://www.geapplianceparts.com/store/parts/spec/GVK8HS

6. 
   Stephen Audretch|Jul 25, 2016 01:30pm|#6

   Thanks for the responses. Bob, appreciate your personal experience with this model and great heads up on clearances. Martin, your answer made me think to just go with a standard water heater. Yes, i understand the volume of air is too small is why i posted since the manufacturer already lists alternatives to accomodate greater air volume to make this possible. John, thank you cause you made me think to still pursue the HPWH. I was just looking for advice on what's the best way to get enough volume of air to keep the efficiency. Does louvered door work best? Air transfer lines? I saw the duct kit as well for this model that appears to just connect to a round duct... does that work even better cause you could even select a differing air input space from output? It at least sounds like the efficiency is still worth it even though the room space alone isn't sufficient.. i can understand why a vent at ceiling and another at the floor would be helpful. thanks for all the responses!

   Stephen