Metlund D’mand System Pumps for Water Heaters – Flow Rate Truth

Metlund D’mand System Pumps for Water Heaters – Flow Rate Truth

I’d like to use today’s blog to answer an email we received which has a number of questions that are asked quite frequently. Maybe if I publish the letter and my answer, I won’t have to answer it again as often?

Here is the email: I am interested in your on demand hot water device chiefly because my bathroom sink and shower are on the opposite side of the house from the water heater, and a tremendous amount of water is wasted waiting for hot water to arrive at those faucets. I have looked at your on-line info and have several questions.

1) I am concerned that the chilipper reports only a 4 gallon per minute flow rate, as opposed the the 8 gpm, 14 gpm, and 28 gpm for the various Metlund models. How is it that one could expect a decent flow of water in the shower and faucet with such a low gpm? I confess, I do not under stand the comments about backflow and feet of head, so maybe that factors in some how

.2) I talked to my handyman (he would be the one to install it) a little about hot water recirulating systems, and he warned me about the ones that ar on all the time, wasting energy. My schedule varies a lot, so having the system on a timer would not work well for me. Therefore, I want to confirm that the Chilipepper operates with what sounds like a simple push of a button or flick of a switch?

3) If I forget to push the button, will the hot water faucets default to their ordinary function, where I would simply have to wait the usual time for the hot water to arrive?

4) I live in an area that has very had water - lots of minerals. What hazards would that pose to the Chilipepper and what maintenance would be necessary to cope with the problem of hard water deposits?

5) I only have one bathroom at this time. It is an eventual goal to add a second bathroom. Would one put another Chilipepper under the sink of a second bathroom to maximize function?I may come up with more questions later, but these were the ones that came to mind initially. Thank you for any information you can provide.Answering the questions in the order asked:

1. Actually I think we say 3 gallons a minute for the Chilipepper. The Metlund site is miss-leading. What they are giving you is the maximum amount of flow the pump can put out if it is not hooked up to anything.

It takes pressure to push water through pipes, and their pumps don't have enough power to develop the required pressure.

Even the Metlund S-02T doesn’t come close to having the power of the Chilipepper pump.Metlund does not recommend the smaller S-50T pump for use with any tankless water heater since it doesn't pump enough flow to turn on the water heater, even if it is less than 50 feet away.

Why? Because it won’t even pump enough water through a tankless water heater to turn it on… typically ½ gallon per minute. So if their pump is rated at 8 gallons per minute why won’t it pump even a ½ gallon per minute through a tankless water heater?

The answer of course is their pump doesn’t produce enough pressure to push that much water through the small diameter tubing in a tankless water heater’s heat exchanger.

I've written a comparison between the Metlund pumps and the Chilipepper pump if you want to read about it. http://www.chilipepperapp.com/Artcls40-Metlund-pump.htm

If you want to read about how my partner and I invented the Metlund system before we got ripped off you can read about it too.http://www.chilipepperapp.com/Artcls31-D-mand.htm

2. Yes, the press of a button turns it on. Then it turns itself off when hot water reaches it.

3. When the Chilipepper is not running, your plumbing system doesn't even know it's there. There will no change in your plumbing systems operation.

4. There are no hard water problems with the Chilipepper and no maintenance is required.

5. It all depends on your plumbing layout. Running the Chilipepper has the same result as turning on the hot water faucet until hot water reaches it and then turning it off. (Except it doesn’t run water down the drain)So you can test your plumbing.

Pretend you are a Chilipepper and turn on the hot water faucet until hot water gets there, and then turn it off. Now go to another fixture and turn on the hot water. If it shares the main hot water run you will get hot water faster.It depends on your residential plumbing layout.

In my house it takes over a minute to get hot water to the kitchen sink. But if I run the Chilipepper which is in the master bath upstairs, and then turn on the kitchen sink faucet I get hot water in 7 seconds. So I have a remote switch at the kitchen sink.

And yes, if need be you can run multiple Chilipeppers in one home.Thanks for your interest in our product!

Bill – The Hot Water Guy