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jimbo770 · Apr 24, 2009, 08:22 PM

Originally Posted by Milo Dolezal

Jimbo: thank you for posting the photos. With your premission, I will print them out and show them to the Rep. I will let you know what he had to say.

Btw: Nice and clean job... Keep the plumber ! :D

By all means, you may print them. The installers have been great. They have also been talking with rinnai, but since we got rated flow at the drain valves , they are saying that there's nothing else they can do, that it must be an issue downstream of the rinnais. I will post my findings when I install the new pressure regulator, and I look forward to hearing any info you get from the folks at rinnai.
Thanks,
Jim

speedball1 · Apr 25, 2009, 05:45 AM

Mllo, Jimbo,
I just spent 10 minutes merging posts that you guys piggybacked on top of each othe. How about simply adding to your post instead of starting a new one. Thamks, Tom.
Plumbing Expert. Lose the advertisements and since nobody appointed you "expert" lose that also. Regards, Tom

jimbo770 · Apr 27, 2009, 10:46 AM

Here is the install of the recirc. Grundfos pump with a comfort valve at the end of the run. They said this will not affect the rinnai warranty, but the pump is on the hot side not the cold side. I have to do some flow tests to see if the flow is reduced, do you think this is going to cause any additional issues regarding flow. I am hoping to get the new pressure regulator this afternoon. I will install it ASAP and report any changes.

jimbo770 · Apr 27, 2009, 10:50 AM

Sorry speedball, the pics didn't upload the 1st time.

Milo Dolezal · Apr 27, 2009, 02:20 PM

Jimbo: Looking at your latest photos, the circ pump set up seems to me to be installed incorrectly.

Sorry, have to run now but will get back to you later with details... Milo

jimbo770 · Apr 27, 2009, 02:26 PM

Originally Posted by Milo Dolezal

Jimbo: Looking at your latest photos, the circ pump set up seems to me to be installed incorrectly.

Sorry, have to run now but will get back to you later with details .... Milo

It definitely is affecting the flow negatively. It is costing me about .5gpm to the shower and 1.0 gpm to the whole house.

According to grundfos, the pump should be supplied on the hot water supply side. I don't have a dedicated hot water return line, so we have a comfort series valve installed in the farthest sink downstream. Do you think there is a way to make this work with the grundfos, or would I be better off with a laing type pump that is installed under the sink that is the farthest away, which would be downstream of the master shower on the hot side.

I would certainly appreciate any suggestions you could make.

I installed the new regulator, and it will give the same flow set at 60 psi versus the conbraco set at 90, also it only drops about 5 psi with hot water demand on the whole house versus the conbraco which dropped 25 psi with the same demand. I guess that is somewhat positive, in that we now have a more reasonable 60psi vs 90 psi previous, but still can't get the rated flow out of the rinnais at the fixtures.

I think I am going to try running a straight run of pex to the rinnais. Can I use 1 1/4" pex instead of 1" in case I am able to find a way to increase the main to 1"? What do you think of running unregulated water to the rinnais?

jimbo770 · Apr 29, 2009, 08:07 AM

I'm starting a new post because I am not able to edit my previous post anymore.

After some research, I have decided on 1" pex to replumb as much of the house as I can access. I have also spoken with the city again (different department) and been told that I can hook a 1" main up to a 5/8" meter. I am going to start this project in another month or so. I still want to install a 1" run directly from the main to the rinnais and from the rinnais to the riser that goes to the master shower, and after the new main is installed fill in the rest of the service with 1" pex.

My question is can I:

1 - Install all the 1" including a 1" regulator now to the 3/4" main (for the next 2 months or so, until the new main goes in)

2 - Install the 1" run to the rinnais only and keep everything else the same

3 - Install the 1" run to the rinnais and from the rinnais to the upstairs rise.

4 - Install all the 1" but keep the 3/4" regulator for now.

I know there will be some loss of volume / pressure as you stated in an earlier post, but there are only 2 people in the house for now, so we wouldn't be using multiple showers etc.

Finally, is there much difference as far as performance (flow, friction loss, etc) between 1" pex and 1" copper. Is wirsbo pex a good choice? IIt is the only pex I can readily find that is available in 1".

Thanks,
Jim

Milo Dolezal · Apr 29, 2009, 07:33 PM

Jimbo, first to your latest photos:

1. Is that Grounfo pump the one designed for Tankless Heaters ?
2. What are its specs ? (gpm / head )
3. Does it come with Grounfo "Comfort Series Valve" in same box/package ?

As far as I know, there is only one LAING pump that will work with Tankless heaters. It is the 909 model. It doesn't come in under-sink version. Moreover, there are two circ-pump systems that Rinnai suggests with their heaters. The system you have is not one of them. I have seen this system used with regular w/h's but never with Rinnai. I looked through Rinnai's installation instructions but nothing even close to your situation.

In addition, the way the tank and pump are installed it seems to me that the tank doesn't really do that much - except slowing down hot water delivery. More over pumps usually pull water, not push. Therefore they don't effect volume delivery. But having the pump to push water forward and through the pump blades - I am sure it will take away from water flow.

Milo Dolezal · Apr 29, 2009, 07:38 PM

After some research, I have decided on 1" pex to replumb as much of the house as I can access. I have also spoken with the city again (different department) and been told that I can hook a 1" main up to a 5/8" meter. I am going to start this project in another month or so. I still want to install a 1" run directly from the main to the rinnais and from the rinnais to the riser that goes to the master shower, and after the new main is installed fill in the rest of the service with 1" pex.

Great Idea.....

My question is can I:

1 - Install all the 1" including a 1" regulator now to the 3/4" main (for the next 2 months or so, until the new main goes in)

Yes, you can. It should not present any problem to the functionality of the system. Maybe, some increase in noise in the 3/4" to 1" transition.

2 - Install the 1" run to the rinnais only and keep everything else the same

Depending if you are experiencing low water delivery to the rest of the house. If positive, than run 1" all the way through out the house. If negative, terminate at Rinnais.

3 - Install the 1" run to the rinnais and from the rinnais to the upstairs rise.

That's what I would do...

4 - Install all the 1" but keep the 3/4" regulator for now.

Ok, for now. But you should upgrade to 1" to maximize water flow...

I know there will be some loss of volume / pressure as you stated in an earlier post, but there are only 2 people in the house for now, so we wouldn't be using multiple showers etc.

With 2 people in the house you will probably never notice ...

Finally, is there much difference as far as performance (flow, friction loss, etc) between 1" pex and 1" copper. Is wirsbo pex a good choice? IIt is the only pex I can readily find that is available in 1".

Pex has no sharp 90 bends. Copper has quite a few of them over the length of the run. Pex will give you better flow, less friction, less noise. Wirsbo is just fine. I think Home Depot now stocks it...

Thanks,
Jim[/QUOTE]

I have sent copy of our conversation to Rinnai engineers aksing them to review it and comment either directly or email their answer to me. Tomorrow I will meet with Rinnai Rep in my area. I will ask him to do the same.

Milo

jimbo770 · Apr 29, 2009, 08:48 PM

Originally Posted by Milo Dolezal

Jimbo, first to your lastest photos:

1. Is that Grounfo pump the one designed for Tankless Heaters ?
2. What are its specs ? (gpm / head )
3. Does it come with Grounfo "Comfort Series Valve" in same box/package ?

As far as I know, there is only one LAING pump that will work with Tankless heaters. It is the 909 model. It doesn't come in under-sink version. Moreover, there are two circ-pump systems that Rinnai suggests with their heaters. The system you have is not one of them. I have seen this system used with regular w/h's but never with Rinnai. I looked through Rinnai's installation instructions but nothing even close to your situation.

In addition, the way the tank and pump are installed it seems to me that the tank doesn't really do that much - except slowing down hot water delivery. More over pumps usually pull water, not push. Therefore they don't effect volume delivery. But having the pump to push water forward and through the pump blades - I am sure it will take away from water flow.

Milo,

The reason they ran the circ this way is because it won't affect the rinnai warranty because the pump flow isn't great enough to fire the rinnais, so the 6 gallon tank heats the water that is circulated by the grundfos until a higher demand is called for. I don't have the model with me and Im on the road until Friday, but the comfort valve did come with the pump

Laing makes 2 pumps for tankless, one for a dedicated recirc line, and I that goes under the sink. My concern is whether the pump will cause the rinnais to fire.

Rinnai recommends either an on dmand pump, which isn't ideal for us or a dedicated recirc line. I am starting to think a few holes in the wall may be a small price to pay. I won't be able to get the recirc line all the way to the most downstream bathroom, but I can get it to about 10 feet away, so that should help. This way I can still use the tank to heat the water in the recirc line, but it won't affect the flow. What do you think.

Milo Dolezal · May 2, 2009, 11:26 AM

Ok, met with Rinnai rep the other day. Unfortunately, they send out this 22 year old guy. He had great, professional, appearance - but new diddly nothing. I gave him the paperwork and asked him to go over it and contact me with his suggestions. Based on my conversation with him - I do not expect too much, though...

Jimbo, I though of another detail: each Rinnai has filter screen built in its incoming valve. Would it be possible that there is a bit of debris inside preventing full flow ? Please, check it out.

jimbo770 · May 2, 2009, 11:46 AM

Originally Posted by Milo Dolezal

Ok, met with Rinnai rep the other day. Unfortunately, they send out this 22 year old guy. He had great, professional, appearance - but new diddly nothing. I gave him the paperwork and asked him to go over it and contact me with his suggestions. Based on my conversation with him - I do not expect too much, though...

Jimbo, I though of another detail: each Rinnai has filter screen built in its incoming valve. Would it be possible that there is a bit of debris inside preventing full flow ? Please, check it out.

Milo,

I have already cleaned out the screens. There was no debris in any of them.

The pump model is UP15 10SUP7P/TLC. The Laing model I was referring to is the ACT-909 for under sink install.

Can I insulate pex the same way I would with copper using polyfoam tubes?

Do you think the 6 gallon heater would still cause a noticeable pressure loss if the pump wasn't there?

Does a dedicated cold water return have to be at the end of the plumbing line or can it just be close?

The grundfos setup provides warm water quickly which we like, but my concerns are 1. the loss of flow, which is a deal breaker for the current setup, and 2. I am wondering about cost to run the system since we both work odd schedules so the pump runs about 16 hours a day currently. The D'mand type pumps still take a quite a bit of time to get hot water to the fixtures but would certainly use less energy heating the water, so a trditional system seems like it would make more sense, and I have no problems with really insulating the pipes as well as I can, but I am still concerned about the operation costs. Electricity is pretty cheap in CO about .11 kwh, but I really don't want to add 50-100 dollars a month for quick hot water.

What would you suggest for a recirc setup?

Also regarding pex, how do you feel about zurn vs. wirsbo? After reading some other forums, it seems most prefer the propex connectors with the expansion technique versus the zurn with the crimp connectors. What are your thoughts? Also how about the brass versus plastic propex connectors? Finally, what is your take on sharkbite connectors? I've only used copper with sweat connections so this is all new to me. It seems the shark bite and brass propex are pretty comparable cost wise, and the plastic propex is quite a bit less expensive, however if I do go with the wirsbo and propex connectors, Id need to get the tool, and so far I haven't been able to find a place to rent me one, so Ill have to buy one.