Hi all,

Recently I purchased a Panasonic DH-3RP1 Water Heater. However, it is found that the DC pump continue working even though i turn off the water to the water heater.

As per the spec, I assume it should be turn off totally when there is not water supply to the water heater.


I had a chat with the seller, the seller tried to obtain information from other (probably his supplier). Seem like the supplier mentioned heater and pump work differently.


Do anyone has this same model and can give me some insight whether am I receiving a faulty unit. Or the supplier is just trying to play his word game.

Thank you.

Thanks.

Able to search online.
https://www.youtube.com/watch?v=hVB6VDGUTn0

It seems like it is kind of design flaw.

quoted from some of the comment:
@manvinderbhullar7821
1 year ago
I recently bought the same model because it said 'Flow Switch' on the box. A flow switch detects the flow of water and turns on the heater when water is flowing  and turns it off to prevent the heater when the water stops flowing. I was under the impression that this would also control the pump (just like the other brands I have used and surely Panasonic can't be worse) but I was wrong.

Now if you leave a water pump running without water in it you will probably damage the pump's seals etc. The motor will not be affected much unless the pump seizes(jams) and then the motor will be locked and the current through it will rise, possibly damaging the motor too.

Sad to say this is a poor design. For example when you have wet your body enough to start soaping your body or shampooing your hair, you turn the water off. But the pump keeps running and then you have to turn the power knob off to preserve the life of the pump. After soaping, you turn the water on and then turn the power knob to the 'on' position.  The knob is round and smooth and now you get soap all over the knob as you grip it hard to turn it with slippery fingers.

If the designers had not intended to control the pump via the flow switch they could have at minimum provided a push on, push off switch or put some curved indentations into the knob. But still, I find it hard to understand why they can't turn the pump off when the water stops flowing. Of course it will increase the cost by a few bucks but it's better than getting bad reviews.

Conclusions:
1)Don't bother with this model.
2) Don't assume anything in future even with big name brands