Water Heater over pressurizing system? Exploding Water Filter Housing

[wmtire]

Originally Posted by wurlitzer28

The snarky "Search is your Friend" is what took me originally to the section where I could NOT post.

One of the problems when sometimes using apps, is it will not show the thread descriptions/explanations as in the screenshot below.

Mr.Dan was not being snarky in the least and as a site team member was attempting to explain why you cannot post or add threads to the FAQ subsection, as you seemed to be asking such in your OP with the ? marks.

The "search is your friend" is in his sigline and has been there for a real long time and was not aimed at your postings. It is in all his posts.

It's all good.

[Bob2019]

I seriously doubt hot water pressure caused the water filter to give way. Those internal filter housings are pretty thick. I have a 5 filter Reverse Osmosis System in my home and the water pressure here is much higher than any RV.

One thought on water temperature: Our water heater RV temperature was just scalding both at the kitchen sink and starting out in the shower. I understand many of the water heaters in RVs have no temperature adjustment. I bought a Atwood 93105 thermostat. It takes about 10 minutes to install on the water heater to cut the water temperature down to a more reasonable temperature. You don't have 140 degree water at home, why have it in a RV,

[TitanMike]

Originally Posted by Bob2019

You don't have 140 degree water at home, why have it in a RV,

I think the reason for the higher temp is due to the smaller tank size than in a residence. Hotter water requires more cold to temper and as such takes less hot water is used and supply lasts longer.

Yes, it can get HOT. Most are aware and act accordingly.

[pgandw]

Originally Posted by TowPro

But.

After a shower tonight the pressure valve was dripping on HW heater. I opened a faucet and there was no blast of high pressure. Tomorrow i will let some air into HW tank to see if it stops dripping while heating.

I was going to remove filter under bed in future. Might be a good place for a small expansion tank.

An expansion tank (5 gal) cured the pressure valves dripping on the water heaters in my house (I have 2 - 1 for each level, but they are tied together). When I was researching, expansion tank size is based on water heater size, so a 6 gal heater should only need a small expansion tank.


Fred W

[TowPro]

My rig had been "live" with hot water tank filled since March.
After a long shower last night i noticed wafer dribbling down the outside side of rv from hot water heater. Checking i saw it was the pressure releaf valve.

Today i shut off water and drained some water out of hot water heater using drain valve wing nut i installed and opening pressure release valve to let air into tank.

Once i let out about 1/2 gallon i turned drain and vent off, turned water on and blead air out of hw lines at sink. Turned hw heater back on and not sean anymore drip at releaf valve.
This valve leaks at 125 psi,?

If your install don't have a winterizing system that uses a check valve i guess this pressure could be transmitted back on cold supply line. And with a check valve on city water inlet i guess it could cause pressure on filter housing.

But i would still expect filter housing to hold with that pressure as that is sort of a design max expected presdure.

[Bob2019]

I'm not a fan of the idea of having super hot water to mix with cold. RVs typically use these cheap plastic faucets and when you start out you have one a valve setting and it changes as it heats up. Start out a a decent mix and you can find yourself in super hot water. Wife and I usually follow each other in a showers and we have never run out of hot water. If you do, you need to cut down the water volume in the shower head and do your job and get out. You don't have a 40 gal heater like at home. You are in a self-contained RV that has limits.

[TowPro]

[QUOTE=Bob2019;2449204Wife and I usually follow each other in a showers and we have never run out of hot water. If you do, you need to cut down the water volume in the shower head and do your job and get out. You don't have a 40 gal heater like at home. You are in a self-contained RV that has limits.[/QUOTE]


I am using a oxygenics Fury RV shower head with the orifice removed, and I am running a regulator on RV for 50psi. great for showers if your on park system water. And if you really are doing "back to back" showers run both electric and gas hot water the same time and it keeps the water warm.

[5picker]

The early FR1 filter housing has had a history of issues. Some of these issues were self inflicted due to folks not knowing how to remove and install the canister due to it having locking teeth (not threads) and having to push up to unlock and pull down to lock. Many folks boogered up the teeth and the canister would "blow off." It happened a lot!

And yes, there have been discussions in the past about what some believe the pressure to get in the system due to thermal expansion but I personally have never experienced 150 PSI.

This winter during an extended stay, I did experience an increase of pressure when the air pocket in the water heater would depleat, but a simple drain of the tank from the T&P valve quickly brought things back to normal.

I often put my pressure gauge on my low point drains to monitor pressure and never seen the extreme numbers being posted. If those numbers were true, we'd see EVERY pump check valve become compromised and you'd never be able to open the toilet valve or sink faucet at 150 PSI without blowing water all over kingdom come.

[Bob2019]

Originally Posted by TowPro

I am using a oxygenics Fury RV shower head with the orifice removed, and I am running a regulator on RV for 50psi. great for showers if your on park system water. And if you really are doing "back to back" showers run both electric and gas hot water the same time and it keeps the water warm.

Great idea I have heard good endorsements about the oxgenics shower head. In our 2 previous TT and now the Forester, we have never, ever ran electric and propane together in our back to back showers.

[eye95]

Originally Posted by TitanMike

I think the reason for the higher temp is due to the smaller tank size than in a residence. Hotter water requires more cold to temper and as such takes less hot water is used and supply lasts longer.

Yes, it can get HOT. Most are aware and act accordingly.

This.

Your water heater is basically producing and storing heat. The amount of heat stored can be increased by increasing tank size or by increasing the maximum storage temperature.

To avoid scalding, learn what position to set your valves in your shower and sink to achieve the desired temperature of the water.

[bubbles]

Originally Posted by Bob2019

I seriously doubt hot water pressure caused the water filter to give way. Those internal filter housings are pretty thick. I have a 5 filter Reverse Osmosis System in my home and the water pressure here is much higher than any RV.

One thought on water temperature: Our water heater RV temperature was just scalding both at the kitchen sink and starting out in the shower. I understand many of the water heaters in RVs have no temperature adjustment. I bought a Atwood 93105 thermostat. It takes about 10 minutes to install on the water heater to cut the water temperature down to a more reasonable temperature. You don't have 140 degree water at home, why have it in a RV,

The Georgetown water filter is a whole house filter and no hot water passes through it. The filter type must have been changed since earlier GT's used the C1 type filters not FR1. If water was coming out of the shore hook up compartment it is not from the water heater.

[MR.M]

Originally Posted by wurlitzer28

I tried to post this in the Water Heater section but, according to that section, I'm not allowed to post. What the????

Not a freezing issue but on a 60F day with only my onboard water pump running.

This 35' Georgetown had been used after the winter on both RV park and internal water pump operation so the water filter housing was at that time OK. No water related issues after the anti-freeze was replaced with potable water.

We set up and turned on the water pump and the water heater. About 15-20 minutes later a loud bang and water was pouring out of the side of the RV's water compartment.

The best I can figure, is when water is heated it expands and if there is no place for it to go, the pressure will rise very rapidly and very high as water does not compress.

What is in the RV to prevent water pressure from rising when the water heater is turned on? If there is no way to relieve pressure these water filter housings should be going off like popcorn so something must be in the system to try and keep this pressure increase under control.

Did you purge the air out of the water heater first ? the T&P valve should relieve psi build up to prevent a dangerous amount unless it failed . So what exactly blew ? a fitting the tank , filter, ?? if it was the filter not uncommon for the cheap filter just a little water in the wrong place that freezes can ruin threads, seals etc

[SailorSam20500]

Originally Posted by TitanMike

I found that turning my pump off at night worked really well for that task.

Before I put the expansion tank in, I tried just turning off the pump. DW was NOT happy...

[TitanMike]

Originally Posted by SailorSam20500

Before I put the expansion tank in, I tried just turning off the pump. DW was NOT happy...

I've been a widower for 4 years now. Rarely get any complaints on ANYTHING I do in the TT.

There may well be heck to pay however in my next life.

[nomad297]

I know I said previously that I had no more to contribute to this thread, but I have been researching Suburban water heaters this week and I feel compelled to share something I came across in the AIRXCEL/Suburban Service and Training Manual for all of their tank-type water heaters. This picture from page 20 of the manual shows the beginning of their tutorial regarding the temperature and pressure relief valve and thermal expansion:

Click on the picture so it will be large enough for you to be able to read it.



I will follow up with what is said in the manual about an air pocket after I find the dimensions of the tank (without insulation), the hot water outlet and for the placement of the temperature and pressure relief valve on the tank — these measurements are critical to determine the efficacy and longevity of the air pocket. I am having a really hard time finding this information. If anybody knows where I can find this, I would really appreciate your help.

Thanks,

Bruce

[Rick the Rocket]

Having seen the effects of petro-chemicals on plastic, I can't wonder about the interaction between anti-freeze and the filter housing. Just a thought.

[mljmam]

Hi,
Our filter exploded also, while dry camping and using the onboard water pump. I never thought about the water heater being a factor. But, I do know that my wife had turned it on in preparation for a shower the morning when the filter housing burst. I would think that a PEX fitting would leak or burst before the water filter housing would. But, I will be looking for a different pressure relief valve for the water heater, with a release level lower than 150#s. That is way too high for the RV system to tolerate without damage. I would much rather have had the pressure valve leak that day instead. Since we were dry camping; which is the only time this scenario would occur, we were about forty miles from nowhere when this happened. Thankfully, there was an amazing hardware store there. It became a parking lot project, as I had to cut away wood, and link multiple sized fittings to make the connections under the bed. We have a 2015 Forestor MBS.
Thanks to everyone for sharing your thoughts.
Safe Travels!

[blasingame]

The water heater should no be an issue as hot water should not be flowing through the water heater. Water should flow from tank to pump through the filter then the water heater.

[myxkp]

A simple possibility; there was mostly air with a little water in the water heater - the t/p valve did not respond to temperature.
It’s at the top of the tank so when pressure built up from the little water in the tank reaching a boil the t/p valve opened with a lot of pressure behind it and bang!
Just a possibility...

[nomad297]

Originally Posted by blasingame

The water heater should no be an issue as hot water should not be flowing through the water heater. Water should flow from tank to pump through the filter then the water heater.

The pressure will increase on both the hot and cold sides — makes no difference which direction the water is flowing. There is no check valve on the cold side of the water heater, so the thermal expansion will occur throughout the entire system.

Bruce