Skip to main content ↑ ↓
Topic: A Pressure Pause While Hot and Cold Water Mixing (Read 396 times) previous topic - next topic

A Pressure Pause While Hot and Cold Water Mixing

Can't think of a better (more intelligently searchable) subject line, but it describes the situation.  Here's the question:

When operating from our fresh water tank, rather than city water connection, we get a pressure drop almost anytime we change the temperature — i.e., move the shower temp control to make it a little hotter or colder, or do the same with kitchen or bathroom sink faucet.

Is there anything that might cause this? We've also been surprised that, when operating from our fresh water tank, the water from the bathroom sink faucet will start quite warm (if that's the way the temp control is set), then get cold, then get warm again.  This doesn't seem to happen when on city water, which starts cold and takes a while to warm up.

I couldn't find a previous thread that described our specific situation, but maybe my search string was no better than the subject I made up for this post!
The selected media item is not currently available.Richard & Susan Peck
____________________
1999 40' U320 "Bob Patrick"
(2000 4010 U320 WTFE Floor Plan, Single Slide)
Build #5567  |  MC #17522

Re: A Pressure Pause While Hot and Cold Water Mixing

Reply #1 –
If it only with on board water, the pressure drop is probably from the increased volume when you open one of the valves more and the water pump has less gph than city water. As for the hot to cold and back to hot again, my Monaco did the same thing and I just lived with it. The Foretravel we have now has a 2 speed water pump and I have not noticed the issue.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: A Pressure Pause While Hot and Cold Water Mixing

Reply #2 –
Quote from: craneman –

As for the hot to cold and back to hot again, my Monaco did the same thing and I just lived with it. The Foretravel we have now has a 2 speed water pump and I have not noticed the issue.


Good tip, 2 speed water pump.  As for the hot to cold, sounds like we'll just live with it, too!  Was mostly curious.  It's not a terrible thing. 
The selected media item is not currently available.Richard & Susan Peck
____________________
1999 40' U320 "Bob Patrick"
(2000 4010 U320 WTFE Floor Plan, Single Slide)
Build #5567  |  MC #17522

Re: A Pressure Pause While Hot and Cold Water Mixing

Reply #3 –
Does your onboard water system have a pressure tankhttp://www.lowes.com/pd_424492-41278-HT2B___?productId=4095287&pl=1&Ntt=pressure+tank? If not they do equalize the water pressure significantly and can be used with either the old single speed or the newer proportional water pumps. Also changing to flexible vinyl hose will make the pump much quieter.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback