Fixing the cold (or hot) shower blast

troutslayer · 04-28-2016, 07:43 AM

Here is a video showing an easy fix for the water temperature imbalance when the RV shower is put on "pause". If you've experienced it, you know what I'm talking about.

https://www.youtube.com/watch?v=BpnNZWdlcfc

weekendwarrior · 04-29-2016, 08:02 AM

Thanks, this is a great video and perfect timing. I haven't noticed this in the past, but this weekend when giving my 2 year old a shower for the first time in the RV this happened. It was the hot that was back feeding into the cold, so he got a little shot of hot water. Screamed for a solid 2 min, poor guy. That prompted me to check the water now every time I turn it on for him, but going to do this as well just to be sure.

Cdash · 05-01-2016, 01:23 PM

I'm less convinced that it's one water back feeding into the other. I really think it's the anti scald feature. I think when you turn off the shower head, it dribbles hot water out (at last it's hot on mine) and fills the shower hose with hot water. Then when you open up the shower head, you get a plug of hot water. I'm going to buy the shut off valve and place it between the faucet and shower hose.

troutslayer · 05-01-2016, 01:33 PM

Quote:

Originally Posted by Cdash

I'm less convinced that it's one water back feeding into the other. I really think it's the anti scald feature. I think when you turn off the shower head, it dribbles hot water out (at last it's hot on mine) and fills the shower hose with hot water. Then when you open up the shower head, you get a plug of hot water. I'm going to buy the shut off valve and place it between the faucet and shower hose.

Report your findings. Would be interesting.

Edd505 · 05-01-2016, 08:22 PM

Quote:

Originally Posted by Cdash

I'm less convinced that it's one water back feeding into the other. I really think it's the anti scald feature. I think when you turn off the shower head, it dribbles hot water out (at last it's hot on mine) and fills the shower hose with hot water. Then when you open up the shower head, you get a plug of hot water. I'm going to buy the shut off valve and place it between the faucet and shower hose.

That is what mine does and after watching the video my first thought was 2 check valves.

spepi · 05-02-2016, 09:21 AM

Quote:

Originally Posted by Edd505

That is what mine does and after watching the video my first thought was 2 check valves.

So you think 2 check valves will make a difference?

spepi · 05-02-2016, 09:24 AM

Quote:

Originally Posted by Cdash

I'm less convinced that it's one water back feeding into the other. I really think it's the anti scald feature. I think when you turn off the shower head, it dribbles hot water out (at last it's hot on mine) and fills the shower hose with hot water. Then when you open up the shower head, you get a plug of hot water. I'm going to buy the shut off valve and place it between the faucet and shower hose.

Is it even possible to get to the line in on the hot at the bottom of the faucet on the 29.5 BHDS? Maybe from the basement? I dont think you can reach the faucet, but the lines are possible I would think

troutslayer · 05-02-2016, 09:51 AM

Quote:

Originally Posted by spepi

Is it even possible to get to the line in on the hot at the bottom of the faucet on the 29.5 BHDS? Maybe from the basement? I dont think you can reach the faucet, but the lines are possible I would think

On my shower, there is a box (of sorts) that the faucet is connected to. I cut the silicone caulk from around the box and removed 4 screws. the H & C water lines are connected to the faucet at the back of this box. As soon as my check valves come in, that is where I will be connecting them and then re-install and re-caulk.

**norty1** · 05-02-2016, 10:31 AM

Did the video mention a source or just locally?

RVhiker · 05-02-2016, 10:38 AM

After setting the water temperature and closing the valve on the shower handle, our shower would be too hot for a few seconds when the handle cut off was turned on again. I put a check valve into the cold water supply close to the shower cold water valve and the problem was solved.

My theory is that hot water migrates through the open shower valves into the cold water line. Thus when the handle valve is turned on, you briefly get a mix of hot with hot water.

That's a good video the troutslayer posted; it shows that the problem could be water too hot or water too cold when opening the handle valve, depending on which side has more pressure. Either way, a check valve on the appropriate supply should fix it.

Edd505 · 05-02-2016, 11:33 AM

Quote:

Originally Posted by troutslayer

On my shower, there is a box (of sorts) that the faucet is connected to. I cut the silicone caulk from around the box and removed 4 screws. the H & C water lines are connected to the faucet at the back of this box. As soon as my check valves come in, that is where I will be connecting them and then re-install and re-caulk.

troutslayer: when you got the shower open were the connections threaded or crimped pex fittings?

spepi: my thinking was two check valves should equal no flow either direction when shut off at the shower head, should be like having the second shut off as depicted in the video.

**norty1** · 05-02-2016, 12:40 PM

Agree, what I got out of that video is to put the check valve on the cold water inlet to the shower.

Cdash · 05-02-2016, 05:13 PM

Quote:

Originally Posted by norty1

Agree, what I got out of that video is to put the check valve on the cold water inlet to the shower.

I didn't get that.

After he installed the check valve, he still had the issue. It wasn't until he put the cutoff that his problem was solved.

That leads me to believe that it is the flow from the anti scald feature (dribble) filling the hose with hot or cold water. Once I get my valve I'll know for sure.

wags999 · 05-02-2016, 05:25 PM

I replaced our hand held with an Oxygenic hand held. When you turn this off, a small trickle of hot water drips.. I have taken showers in snowstorms and never had any "cold starts". And I always take a Navy shower... (actually learned on board ship) . Much easier than putting check valves etc.. plus...check valve does nothing about the water in the line, cooling off due to low temps. JMHO

jwmercer · 05-02-2016, 05:28 PM

So we all know this is going to happen. How about, just point the shower head at the floor of the shower when you turn the water back on!

Cost of fix $0
Effort required 0
Water wasted 3 to 4 Oz
��

troutslayer · 05-02-2016, 06:33 PM

Quote:

Originally Posted by norty1

Did the video mention a source or just locally?

Camco 23303 check valve and KES K1140B (both around $10/ea). I purchased from Ebay cuz they had free shipping. Amazon had free shipping with minimum $49 purchase.

**norty1** · 05-02-2016, 06:34 PM

In the video, seems like he put the check valve on the hot input. I know how to get out of the way but cold is not the problem, it's the momentary flash of hot that I'm looking for a fix.

troutslayer · 05-02-2016, 06:37 PM

Quote:

Originally Posted by Edd505

troutslayer: when you got the shower open were the connections threaded or crimped pex fittings?

Pex fitting crimped onto a female threaded fitting that connects to the male threaded faucet fitting. The check-valve will go between the two threaded fittings. Looks "eazy-peazy"

troutslayer · 05-02-2016, 06:39 PM

Quote:

Originally Posted by norty1

In the video, seems like he put the check valve on the hot input. I know how to get out of the way but cold is not the problem, it's the momentary flash of hot that I'm looking for a fix.

That's my problem as well. So, the check valve goes on the cold...right? Cuz you want to keep the hot water from infiltrating the cold water line.

spepi · 05-03-2016, 03:57 PM

I ordered my valve shut off today. I really dont think I can access the line in to add a check valve. Should have it Thursday.

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