IMO- $$$ and code compliance (drain pan and possible TET install). There was an extensive discussion on this some time back.
You might GOOGLE- Gravity Fed Hot Wafer Recirculation
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Hot water recirculators
- Thread starter rediranch
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IMO- $$$ and code compliance (drain pan and possible TET install). There was an extensive discussion on this some time back.
You might GOOGLE- Gravity Fed Hot Wafer Recirculation
Just figured I'd post about the results.
I installed the Grundfos Comfort Auto pump, even though I was worried about the auto sensing feature.
First, I'd like to report that the Grundfos instructions ARE HORRIBLE
, and they didn't even mention an isolation screw on the side of the base that as shipped prevents any flow. After installing it and not getting anything, referring to the picture only instructions that didn't even show the screw, I turned the screw and then it started working.
Anyway, we just got through a winter with it, and we really, really like it.
For all of our sinks, within 3 seconds the water is warm. Within 9 you have to turn on cold water or it's too hot, after 15 it's as hot as it's going to get (pretty hot).
That warm water after 3 seconds used to take 50 seconds at our kitchen sink and master bath sink.
Another note - I was worried about the auto sensing, since our schedule is all over the place when we use hot water. This model, which replaces their old one that had a scheduler built into it, only has Auto sensing, 100%, temp mode. Note, however, that when the power shuts off (like it would for a switch operated outlet), when it comes back on it sets itself to Auto, automatically. You have to go to the pump and press the button to make it go to one of the other modes.
Because of that we've been using the Auto sensing, but it seems to be doing well. I am not quite alert enough when I wake in the middle of the night to do something, so I actually haven't tried to see if the hot water reacts the same as it does in the day or not. I do note that we seem to have the hot water recirculating from when our day typically starts (5am) to when we go to bed (10pm).
Lastly, cost of running the pump. We are on natural gas, and we are using 6-9 more therms each month, for a total of $5 more a month . That's with the pump running at least from 5am to 10pm, and running return lines. I have two loops from my hot water heater, one being 30' long and the other being 45' long, approx.
I installed the Grundfos Comfort Auto pump, even though I was worried about the auto sensing feature.
First, I'd like to report that the Grundfos instructions ARE HORRIBLE
, and they didn't even mention an isolation screw on the side of the base that as shipped prevents any flow. After installing it and not getting anything, referring to the picture only instructions that didn't even show the screw, I turned the screw and then it started working.Anyway, we just got through a winter with it, and we really, really like it.
For all of our sinks, within 3 seconds the water is warm. Within 9 you have to turn on cold water or it's too hot, after 15 it's as hot as it's going to get (pretty hot).
That warm water after 3 seconds used to take 50 seconds at our kitchen sink and master bath sink.
Another note - I was worried about the auto sensing, since our schedule is all over the place when we use hot water. This model, which replaces their old one that had a scheduler built into it, only has Auto sensing, 100%, temp mode. Note, however, that when the power shuts off (like it would for a switch operated outlet), when it comes back on it sets itself to Auto, automatically. You have to go to the pump and press the button to make it go to one of the other modes.
Because of that we've been using the Auto sensing, but it seems to be doing well. I am not quite alert enough when I wake in the middle of the night to do something, so I actually haven't tried to see if the hot water reacts the same as it does in the day or not. I do note that we seem to have the hot water recirculating from when our day typically starts (5am) to when we go to bed (10pm).
Lastly, cost of running the pump. We are on natural gas, and we are using 6-9 more therms each month, for a total of $5 more a month
. That's with the pump running at least from 5am to 10pm, and running return lines. I have two loops from my hot water heater, one being 30' long and the other being 45' long, approx.
