Water Pump strainer on 2016 MB

cbaarch

2016 Unity MB
We recently bought a 2016 MB - the water pump does not have a strainer. Trying to figure out if that was normal for that year.
Only reason this has come up is that I am experiencing hammering and looked at the setup so wondering if I should add one when I work on the system.

I went to our local hardware store to look for fittings; the salesman who owns an RV said all he did was T off a 24" PEX pipe and capped it.
I will be trying that first as that is the cheapest and the same fittings can work to replace the PEX with a water head arrester like found on hot water tanks in my house.
If that still does not work I will look at the Shurflo accumulator tank as suggested.
The accumulator is the most expensive option when buying in Canada so the other solutions are worth a try.
 

michaelh

2015 Unity TB
Can you tell us what brand / model water pump you have? We have 2015 TB but no accumulator. Did they change the plumbing in 2016, or did you retrofit it?
 

cbaarch

2016 Unity MB
I have not changed anything but I am the 3rd owner; I am trying to figure out what might be stock and if it included a strainer.
it is a Shurflo Revolution Water Pump Mfg# 4008-101-A65 sitting on vibration blocks then connected directly to the PEX pipe which does not have much slack.
I am looking at making modifications to try to solve the noisy pump when only 1 tap is open - it is much quieter when running both the bathroom and kitchen taps.
 

mikeme

2015 LTV IB: 2015 3500 V6
Original plumbing includes a pre-pump strainer, and use of some non-PEX plumbing to/from the pump. This is reinforced vinyl tubing, which has more give than the PEX.

These guys make and will sell you a pump controller that will make things more quiet.
 

Abe123

New member
I am pretty sure what you are hearing is normal sounds from the rv pump. There is a recent post about a product that helps silence the normal pulsing sounds.
 

TampaSteve

2018/2019 Unity CB
My only experience with water pumps was in a boat I used to own. It had an accumulator tank and was quiet as expected. When I bought my LTV I immediately noticed the loud sounds which varied from hammering to chainsaw. The pump is apparently designed to operate like that so for now we just left it alone.
 

michaelh

2015 Unity TB
I have not changed anything but I am the 3rd owner; I am trying to figure out what might be stock and if it included a strainer.
it is a Shurflo Revolution Water Pump Mfg# 4008-101-A65 sitting on vibration blocks then connected directly to the PEX pipe which does not have much slack.
I am looking at making modifications to try to solve the noisy pump when only 1 tap is open - it is much quieter when running both the bathroom and kitchen taps.
It is a bit noisy. Part of the problem is that it's mounted on the wooden floor which just amplifies the sound. You have the original pump. This type of pump should not be used with an accumulator tank.
However, you might want to take the pump out and take the pump head off, and inspect the diaphragms. Don't touch the pressure adjusting screws because if they get out of adjustment, it's a real problem.
 

alichty

2014 LTV Unity TB
It is a bit noisy. Part of the problem is that it's mounted on the wooden floor which just amplifies the sound. You have the original pump. This type of pump should not be used with an accumulator tank.
However, you might want to take the pump out and take the pump head off, and inspect the diaphragms. Don't touch the pressure adjusting screws because if they get out of adjustment, it's a real problem.
I have this same pump in my 2014 TB connected to a Shurflow accumulator I installed several years ago installed and it works just fine. It does smooth out the water flow considerably but sometimes right after I fill with fresh water I will get a hammer effect for a few minutes but it always goes away. Much quieter operation of the water pump overall.
 

TJLee089

2013 Itasca Reyo 25R
I suspect what you are hearing is the normal sound when the flow is low and the pump very quickly shuts off and on. It is not "hammering" in the normal sense. Is the noise significantly reduced when the flow is high? If so, this is normal. An accumulator will significantly reduce this problem; a capped off tee, not so much.
 

Kajtek1

2015 long/tall limo RV 2.1l
Variable output pumps come on USA market about 15 years ago and seems they did not catch much market attention.
When I can only wonder how much the high price plays the role, RV owners go for reliability and "simpler is better" always applies.
Now the pump suppose to be mounted with rubber hoses on both ends and properly bolted with flexible grommets.
When done right, it will not be louder than water splashing in the shower, or AC running.
 

cbaarch

2016 Unity MB
An analogy for what i hear.
The hammering sound is like a steel hammer hitting solid wood in rapid succession; normal operation of the pump when it is not hammering is like a rubber mallet hitting solid concrete floor at a slow rate.
We emptied the fresh water tank for storage so we had both the kitchen and bathroom faucets running; the pump was making a rubber mallet sound which I can live with. The steel hammer sound is what I am trying to eliminate.

I have an email to LTV to find out about the need for a strainer on the intake side of the pump; which is mentioned in one of their maintenance videos.
the white water lines are vinyl braided; rated for water at 150 psi; 3/4" outside diameter attached using PEX crimp ring.
PVC pipe on RV water pump 2.jpg
the pump is installed on a piece of 3/4" plywood (painted black) above the floor using basic vibration isolation anchor points
Water pump on plywood.jpg

I will report back after I have installed something between the pump and the filter.
and what LTV says about the "missing" strainer
 

Tannys

2016 Unity TB
You have the original pump. This type of pump should not be used with an accumulator tank.
Can you explain or provide any additional information to back up this statement? I know that many Unity owner’s have added an accumulator tank without issue and with improvement in the pump noise issue.
 

Kajtek1

2015 long/tall limo RV 2.1l
Accumulator will not change the noise. It will change the noise intervals and allow for small night use without starting the pump.
I discover that some water heaters will hold air bubble with the same effect. That is why when I hook up city water connector with empty hose, I run hot water first, so the air goes to wh - replenishing the air.
Also my impression is that vertically -mounted pumps make less noise. Might be Placebo effect thought
 

Mein Sprinter

2010 Roadtrek SS Agile
Have you thought of adding pressure to the accumulator tanks. Sometimes over the months or years it loses air pressure!


cheers...
 

cbaarch

2016 Unity MB
in the email back from LTV
"...You should have a strainer on the pump otherwise the pump will not last long. ..."

It will remain a mystery if there ever was a strainer installed and or removed at some time before I owned the Unity.
 

Mein Sprinter

2010 Roadtrek SS Agile
in the email back from LTV
"...You should have a strainer on the pump otherwise the pump will not last long. ..."

It will remain a mystery if there ever was a strainer installed and or removed at some time before I owned the Unity.
Have had this strainer next to my Surflo water pump since 2010. Occasionally, open and clean it during the season.


Cheers...
 

Mein Sprinter

2010 Roadtrek SS Agile

SSTraveler

2014 LTV Unity Murphy Bed
in the email back from LTV
"...You should have a strainer on the pump otherwise the pump will not last long. ..."

It will remain a mystery if there ever was a strainer installed and or removed at some time before I owned the Unity.
Orginally there was definitely a strainer, you can see it in the picture in your Leisure Owners Manual, page 97. You can learn a lot reading the owners manual.
Screenshot_20200925-093555_Adobe Acrobat.jpg
 

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michaelh

2015 Unity TB
Can you explain or provide any additional information to back up this statement? I know that many Unity owner’s have added an accumulator tank without issue and with improvement in the pump noise issue.
According to Shurflo, "no need for an accumulator with by-pass pumps". That's because the pump's shutoff depends on getting to the set pressure. An accumulator will dampen the pressure increase, so the pump may stop and start a couple of times before it finally gets to the set pressure throughout the system. There's no real problem in installing an accumulator, but if the pump is working properly, there's no advantage either.
 

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