Like many others I was not very happy with how loud the water pump was in my fancy new toy hauler (2015 Raptor 332TS). My previous camper was a 1999 Lance 1130 truck camper which you could definitely hear the pump but it just seemed different. In the new trailer it was louder and just gave the feeling that things were vibrating because of it. So after reviewing lots of threads on here about what could be done I decided it was worth the effort to try and quite it down.
Step one was to start opening access areas and see exactly how things were laid out from the factory. Fortunately there is plenty of space to get at the pump and most of the water lines after removing a couple panels in the pass through storage compartment. It is also fortunate that I reviewed several posts on here before hand so I wasn't all that surprised by the lack of organized routing.
Once I had an idea of the space available and the basic layout I decided I wanted to go ahead and try an accumulator tank. Based on several reviews on Amazon as well as on here that referenced its use in RV applications I went with this one.
WaterWorker HT-2B In-Line Pressure Well Tank, 2-Gallon Capacity. A trip or two to Lowes was needed to get the appropriate fittings for connecting it on the outlet side of the water pump. This consisted of a ¾” tee, ¾” to ½” bushing, and a short nipple for the original flex connector to attach on the output side of the tank. The other side of the tee needed a ¾” MPT to ½” barb fitting, a short piece of pex, and a barb to flex connector to connect to the output side of pump. In order to get the tank to fit near the pump and not put too much stress on existing water lines the accumulator tank needed to sit at a bit of on angle. Using some scrap wood that I had laying around I built a stand to hold the tank at an angle that seemed to work well. Since the goal was to reduce noise I followed the advice found in other posts and sandwiched some floor mat foam between two pieces of plywood. The water pump has rubber feet for mounting so the foam was probably not necessary but I had some extra pieces so went ahead with it anyway. I secured the tank to the stand with some pieces of nylon strap. It seems to hold it in place securely but will keep an eye on it over the next few trips to see if it loosens up.
At this point I hooked everything up and gave it a test. It takes the pump about 30 seconds or so to pressurize the system. I set the pre-charge on the accumulator tank at 25psi since the max psi listed on the pump is 50psi. With this setting I get about 15 seconds of water out of the bathroom sink with the cold side fully open before the pump kicks on. See below for some actual DB noise measurements taken after this step was completed.
In order to reduce vibration noises I started following the water lines all the way to the bathroom and kitchen and wrapped the lines with insulating foam anywhere that they rested against the floor, frame, through holes, or anything else that looked like it would transfer vibrations. I went through two 5’ lengths of foam. One was for ½” diameter pipe and the other was for 1-1/2” pipe. I’d simply cut off a short length and create a buffer between the pex and whatever hard surface it was resting against. I'll added a couple pictures to give examples of how I placed the foam in another post since I can only put four in a single message.
In order to measure how effective my effort was at reducing noise I loaded a simple noise analyzer onto my iPhone. I doubt it is a very accurate measurement device but it seems to give consistent measurements on repeated tests and it was free. For all the measurements I placed the phone on the bed near the bathroom door (door open) and let the dB meter free run. With no water on I get a steady 28-30 dB reading. Before any modifications the pump running with bathroom sink on was 60+ dB. With just the accumulator added prior to adding any foam I’d get about 45 dB with the faucet on. Once the pump kicked on it jumped up to about 55 dB. After adding the foam to isolate the pipe from hard surfaces it dropped to about 50 dB with the pump and faucet on. With the just the pump running and no faucet it would hover between 45-50 dB. To the ear it sounds much better in my opinion. The pump has a deeper sound since it is working against the pre-charge of the accumulator tank. Before any modifications it sounded like something was broken and you could almost feel the vibration when the pump was running. Time will tell on how it all holds up but overall I think it was worth the effort.
Sam