Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×


Reply
 
Thread Tools Display Modes
 
Old 05-17-2017, 11:59 AM   #1
Bus Nut
 
warewolff's Avatar
 
Join Date: Sep 2016
Location: NY
Posts: 487
Year: 2000
Coachwork: Carpenter
Chassis: International 3800
Engine: T444E
Pump placement

So I'm getting around to installing my water system and I'm having a brain fart. The correct sequence is Water tank ---> water pump ---> T split ---> one goes to hot water heater then to sink/shower hot, other side goes to sink/shower cold

Is that correct? That way both sides have pressure from the pump. I was then going to install a switch under the sink so that I could flip it, turn the pump on, and have hot/cold water. Don't want to mess this up and definitely not a plumber.

__________________
Roads? Where we're going, we don't need ... roads.
warewolff is offline   Reply With Quote
Old 05-17-2017, 12:19 PM   #2
Bus Geek
 
ol trunt's Avatar
 
Join Date: Apr 2012
Location: So Cal
Posts: 3,227
Year: 1935
Coachwork: Superior
Chassis: Chevy
Engine: 317 ci/tid / Isuzu
That'll work with a conventional rv water heater. If you use an on demand water heater you should use separate pumps as most on demand heaters have both flow and pressure requirements that a single pump probably won't handle.

Jack
ol trunt is offline   Reply With Quote
Old 05-17-2017, 12:53 PM   #3
Bus Nut
 
warewolff's Avatar
 
Join Date: Sep 2016
Location: NY
Posts: 487
Year: 2000
Coachwork: Carpenter
Chassis: International 3800
Engine: T444E
Quote:
Originally Posted by ol trunt View Post
That'll work with a conventional rv water heater. If you use an on demand water heater you should use separate pumps as most on demand heaters have both flow and pressure requirements that a single pump probably won't handle.

Jack
I was looking at on demand. I can't use a heavy duty Shur-Flo pump?
__________________
Roads? Where we're going, we don't need ... roads.
warewolff is offline   Reply With Quote
Old 05-17-2017, 02:31 PM   #4
Bus Geek
 
ol trunt's Avatar
 
Join Date: Apr 2012
Location: So Cal
Posts: 3,227
Year: 1935
Coachwork: Superior
Chassis: Chevy
Engine: 317 ci/tid / Isuzu
Check the requirements on which ever heater you are looking at and make your pump selection accordingly. Error on the side of higher flow rate and pressure under full flow. Too little pressure or flow if even a bit will cause your heater to cycle on and off resulting in occasional bursts of cold shower water---burrrrrr. Definitely plan on two pumps if you go with the on demand heater. Both can be operated by a single switch and will operate without regard to each other.

I use an on demand heater in my bus which has a recirculating circuit on the hot side so never a lack of hot water.

Jack
ol trunt is offline   Reply With Quote
Old 05-17-2017, 03:24 PM   #5
Mini-Skoolie
 
Join Date: Jul 2016
Location: Colorado
Posts: 49
Year: 1998
Coachwork: BlueBird
Chassis: TC2000FE
Engine: 5.9L Cummins ISB
Rated Cap: 71
Most tankless water heaters have a 1/2gpm flow sensor.
(will not fire with less than 1/2gpm flow)

One pump is adequate. No need for more than 1. Just make sure you can get more than 1/2gpm when factoring in the pressure drop of the pipe size and length (and any other potential flow restrictions you build into the plumbing system)

I'm not a bus expert, but if you have plumbing questions, fire away!
ColoradoCummins is offline   Reply With Quote
Old 05-17-2017, 05:26 PM   #6
Bus Crazy
 
Join Date: Feb 2012
Location: Salt Lake City Utah
Posts: 1,635
Year: 2000
Chassis: Blue Bird
Engine: ISC 8.3
The cheapest of the demand heaters (for example, Eccotemp) use a pressure switch rather than a flow sensor. Those are the heaters most likely to need dual pumps in order to develop enough pressure to reliably keep the unit fired. I have the Eccotemp L5 and have done a few experiments with it. I don't think a person would be happy with the result if they tried to mix hot and cold water to get the shower "just right" -- that heater seems to be designed so that one adjusts the flow knob until the flow is low enough (pressure is high enough) to keep the burner lit, then adjust the gas knob to get the temperature right. Running cold water elsewhere could upset the balance of the flow knob and cause the unit to extinguish due to low water pressure... which can be "fixed" by the addition of a second pump as ol trunt suggests, or by using a better heater with a flow switch instead of a pressure switch.
family wagon is offline   Reply With Quote
Old 05-17-2017, 06:47 PM   #7
Bus Crazy
 
Stu & Filo. T's Avatar
 
Join Date: Sep 2013
Location: Vacaville, Ca
Posts: 1,634
Year: 1988
Coachwork: Crown / Pusher
Engine: 8.3 Cummins
If your going to have a hookup for city /park water I would put a check valve just after the pump.
Stu & Filo. T is offline   Reply With Quote
Old 05-17-2017, 08:26 PM   #8
Bus Geek
 
ol trunt's Avatar
 
Join Date: Apr 2012
Location: So Cal
Posts: 3,227
Year: 1935
Coachwork: Superior
Chassis: Chevy
Engine: 317 ci/tid / Isuzu
S&F. That would be a good idea--it would prevent any chance of city water passing backwards through the pump and over filling the water tank.

CC and FW, I use the Ecotemp L5 and I can assure you that it requires both an adequate flow rate and adequate water pressure per the owners manual and personal experience.

Until I solved those problems the Ecotemp was on my s#@t list. Though I can't provide the specific pump model Ecotemp recommends without opening my water heater cabinet (lots of screws), it can be easily found on one of the Ecotemp websites.

As to two pumps, for the $50 they cost, why would anyone risk the failure of a single pump while dry camping miles from nowhere? I don't see anything sporting about trying to get my next drink from the run off in the rain gutter.

Jack
ol trunt is offline   Reply With Quote
Old 05-17-2017, 08:51 PM   #9
Bus Nut
 
warewolff's Avatar
 
Join Date: Sep 2016
Location: NY
Posts: 487
Year: 2000
Coachwork: Carpenter
Chassis: International 3800
Engine: T444E
I'm not trying to cheap it, but K-I-S-S. I saw the higher end Shur-Flo's have 3gpm. I have the Ecotemp L10. Neither of these products are cheap. If two pumps is the way to go I'll do that. I have no city hookups. My bus is fully off grid. I was worried more about power requirements but even 5 amps each for the duration of a shower is not going to put a dent in my battery bank.
__________________
Roads? Where we're going, we don't need ... roads.
warewolff is offline   Reply With Quote
Old 05-17-2017, 11:32 PM   #10
Bus Crazy
 
Join Date: Jun 2016
Location: Orange County, CA
Posts: 1,358
Year: 1990
Coachwork: Crown, integral. (With 2kW of tiltable solar)
Chassis: Crown Supercoach II (rear engine)
Engine: Detroit 6V92TAC, DDEC 2, Jake brake, Allison HT740
Rated Cap: 37,400 lbs GVWR
Quote:
Originally Posted by ol trunt View Post
S&F.
As to two pumps, for the $50 they cost, why would anyone risk the failure of a single pump while dry camping miles from nowhere? I don't see anything sporting about trying to get my next drink from the run off in the rain gutter.

Jack
Like Jack, I have two pumps, in my case the good ol' Shurflo 2088 that are simple and work well, and are probably still the most reliable pump out there. I mounted each one on an easily-removable shock-absorbing mount and use quick-connects for the water lines and power wires - this way it takes less than a minute with no tools to completely remove a pump for any servicing or PM. Pumps are cheap enough that it's silly to not have a spare or back-up pump connected and ready for immediate use. To make it easier to diagnose problems, I have two 100 PSI gauges, one for incoming city water pressure and the other for in-bus water pressure; I set each pump's internal regulator to 40 PSI, the same as the Watts adjustable brass regulator, then I always have 40 PSI whether I'm on tank or city water.

John
Iceni John is offline   Reply With Quote
Old 01-04-2018, 05:39 PM   #11
Mini-Skoolie
 
Join Date: Dec 2014
Posts: 19
Year: 1996
Coachwork: Goshen
Chassis: frieghtliner mt55
Engine: cummins isb
Rated Cap: 25
Warewolf, how did you end up connecting your system? I just ordered an L10 and am looking into options.

2 pumps the way to go?
one water tank?
did you use a purge tank or regulator tank - or are the pump(s) connected directly to the water tank?

thank you!
Omingnome is offline   Reply With Quote
Old 01-04-2018, 05:51 PM   #12
Bus Nut
 
warewolff's Avatar
 
Join Date: Sep 2016
Location: NY
Posts: 487
Year: 2000
Coachwork: Carpenter
Chassis: International 3800
Engine: T444E
Quote:
Originally Posted by Omingnome View Post
Warewolf, how did you end up connecting your system? I just ordered an L10 and am looking into options.

2 pumps the way to go?
one water tank?
did you use a purge tank or regulator tank - or are the pump(s) connected directly to the water tank?

thank you!
Just one pump. 1/2" PEX comes out of my water tank and into pump. Hot/cold T is upstream. My pressure is sufficient.
warewolff is offline   Reply With Quote
Old 07-06-2018, 03:03 AM   #13
New Member
 
Join Date: Dec 2017
Posts: 6
Long-distance plumbing

Quote:
Originally Posted by ColoradoCummins View Post
Most tankless water heaters have a 1/2gpm flow sensor.
(will not fire with less than 1/2gpm flow)

One pump is adequate. No need for more than 1. Just make sure you can get more than 1/2gpm when factoring in the pressure drop of the pipe size and length (and any other potential flow restrictions you build into the plumbing system)

I'm not a bus expert, but if you have plumbing questions, fire away!
I would love some help plumbing! I am having my first child on my bus in a month and trying to figure out the plumbing before then... trust me wasn't my first option but here we are! I was set on the Sureflo 4008 3gpm - I just got done installing a rain barrel that I will either fill or let be filled with potable water on the back of my 22ft Bluebird....

I foolishly thought that I could just pump water up to the kitchen 15 or so feet away and a couple of feet vertical from the barrel spout but then read the manual and it has to be 6ft or closer to the water source. I could just use the rain barrel as storage and fill 2.5 or 5 gal jugs when I need to but given my circumstance, I want to be able to pump water into the cabin when I need it, for now.

Electricity is also in the works, amperage and voltage are all covered so I just need to figure out a way to pump long distance - and eventually how I'll heat it when I need to. Without much experience I'm not able to put plans together very well- help!
mad.am.scientist is offline   Reply With Quote
Old 07-06-2018, 07:00 AM   #14
Bus Crazy
 
somewhereinusa's Avatar
 
Join Date: Nov 2010
Location: Andrews,Indiana
Posts: 2,430
Year: 1991
Coachwork: Bluebird
Chassis: AARE
Engine: 3116 Cat 250hp
Rated Cap: Just the two of us.
Quote:
I foolishly thought that I could just pump water up to the kitchen 15 or so feet away and a couple of feet vertical from the barrel spout but then read the manual and it has to be 6ft or closer to the water source.
I just downloaded the manual. What it says is the pump must be within 6 ft of the water source (tank). It makes no mention of how far it will pump (push) Your 22 foot bus would never have such a long water system to be a problem.

These pumps don't lift (suck) very well but, they push quite well. If you have a water outlet on the bottom of the tank and mount the pump as low as the outlet it will be more than enough. Even if you stick a hose in the top of a barrel and mount the pump on top of it, it would meet those specs.
somewhereinusa is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 07:23 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.