How to Make Your RV Water Pump Quiet

A noisy water pump is a very common complaint among RV owners. Some RV manufacturers use the cheapest pumps and suspect installation methods to reduce cost but this often results in water hammer, clanging pipes, and floor vibration.

By following these simple, low cost steps, you will be on your way to rattle-free water pump nirvana.

Difficulty: Easy

Instructions

Things You'll Need:

• 1/2" foam pipe insulation
• A rubber computer mouse pad
• A Phillips head screwdriver
• A helper

1. 
   Water pump under the dinette

   Ensure that the water pump is turned off then locate the water pump in your RV. Typical locations are under the dinette, under the bed, or in a cabinet near the sink. If you can't find it, turn on a faucet and locate the noise coming from the pump (this should be really easy!).

2. 
   Close-up view of mouse pad under water pump

   A typical water pump will be secured by 4 screws. Remove these 4 screws and slip a rubber mouse pad under the pump. Re-secure the pump being careful to not over tighten the screws. Using a mouse pad will help absorb the vibrations from the pump to the floor.

3. 
   Cold water pipe under tub clanging against tub support brace

   Next, we will locate the rattling water pipes. Turn on the pump. Have a friend open and close any faucet while you try and locate where the clanging noise is coming from. Typical areas are where the cold water pipe passes through or runs along a cabinet wall. In this case, the cabinet acts like a sounding board and creates a lot of noise.

4. 
   Cold water supply for water filter and kitchen sink

   Take some 1/2" foam pipe insulation and wrap the pipe where it rattles against the cabinet or flooring. It should slip right over and not require any securing to the pipe. But a little duct tape on each end of the insulation wouldn't hurt. Repeat this step until you have insulated all rattling pipes.

5. 
   Water pump cycle adjustment screw

   Sometimes the water pump can rapid cycle on and off (cycling ON/OFF in less than 2 seconds) during low flow conditions. This can cause pulsations in the water system and create noise.
   
   To determine if adjustment is necessary, turn a faucet ON to lower than average flow of water. The pump should cycle, but its "OFF time" must be 2 seconds or longer. If the cycling is correct, no adjustment is necessary. If the pump is cycling rapidly, increase the setting by turning the adjustment screw (see image) clockwise (1 turn MAX.) until the pump operates for 1 sec. with at least 2 sec. "OFF time".

Tips & Warnings

• Most RV water pump manufacturers recommend at least 1 foot of flexible high pressure tubing to both the inlet and outlet ports of the pump. This helps to ensure that the pump's normal oscillations are not transmitted to the rigid plastic pipes that run throughout the RV.
• If you still experience too much noise, the pump can be replaced with a variable speed pump. These are not inexpensive however but they do dramatically reduce hammer and vibration.
• Another alternative is to install an accumulator, which is bladder type pressure storage vessel and/or pulsation dampening device designed to hold water under pressure. The accumulator tank provides additional water storage to assist the pump in meeting the total demands of the system. It extends pump life by eliminating the pump from pulsating on and off, and also makes water available at a moments notice without cycling the pump.

Resources

• RV Mods and How-to's

[jjfitts]

on 9/29/2007 Great low cost solutions to some annoying problems.