Low Hot Water Pressure

[woodster]

don't know what valve you have but most are straightforward ...pull the adjusting knob ...it may have a screw in the middle on a splined shaft ....after that should be a retainer of some kind nut or snap ring...then o ring or packing and then the valve cylinder and maybe a seat of some sorts...then if it is the valve that is causing the problem clean it and back together

...but it would be nice to know if you should accidently break it you could purchase a new one and be done with it

 

[quadrille38]

don't know what valve you have but most are straightforward ...pull the adjusting knob ...it may have a screw in the middle on a splined shaft ....after that should be a retainer of some kind nut or snap ring...then o ring or packing and then the valve cylinder and maybe a seat of some sorts...then if it is the valve that is causing the problem clean it and back together ...but it would be nice to know if you should accidently break it you could purchase a new one and be done with it

Thanks
I will give it a go. But agree with you on needing mfg information so I can hunt down a replacement should it be necessary.

I did find another string on the site that focuses on mixing valves and in it there were two links to sites for them. So regardless of the brand the biggest challenge as always will likely be getting one that fits in the same small space and doesn't need a lot of re-plumbing work.

 

[Jake N Eggs]

Thanks
I will give it a go. But agree with you on needing mfg information so I can hunt down a replacement should it be necessary.

I did find another string on the site that focuses on mixing valves and in it there were two links to sites for them. So regardless of the brand the biggest challenge as always will likely be getting one that fits in the same small space and doesn't need a lot of re-plumbing work.

This is the valve that is on my 2006 H33. http://www.wattscanada.ca/pages/_products_details.asp?pid=841

 

[quadrille38]

Thanks

From the picture I think it looks like the same one
Will confirm

 

[quadrille38]

Well I got back to the boat and confirmed it is the same model valve and of course when you look it up on the Watts web site it says its a discontinued model and there is no schematic.

Not to be discouraged I took it apart anyway. Got it all apart, cleaned thoroughly and still not getting flow. Suspect there is a clog somewhere that I can't see or reach. Gave up and ordered a new one. Pricey little things at $71.00.

 

[woodster]

another way to check and see if it is indeed the valve is to bypass it all together ......if you have good flow without it there is your answer...if not better look else where

 

[quadrille38]

another way to check and see if it is indeed the valve is to bypass it all together ......if you have good flow without it there is your answer...if not better look else where

Thanks I did that. In fact if I adjust the mixer to full cold I have excellent flow. As I turn the knob to get warmer water the flow decreases to a dribble.

 

[woodster]

Thanks I did that. In fact if I adjust the mixer to full cold I have excellent flow. As I turn the knob to get warmer water the flow decreases to a dribble.

that makes me think your valve or some behind that is the problem...di you take the valve completely out and pipe the hot water direct to the hot water feed pipe or just turn the valve

 

[quadrille38]

that makes me think your valve or some behind that is the problem...di you take the valve completely out and pipe the hot water direct to the hot water feed pipe or just turn the valve

Yes I did

According to the literature there is a check in the mixer but since they don't publish a schematic it's difficult to see all the moving parts.
What really decided it for me was that the pricing I was seeing for the repair parts were nearly as much as a replacement so I decided to just replace it and spend time going sailing rather than doing plumbing. ?

 

[woodster]

Yes I did

According to the literature there is a check in the mixer but since they don't publish a schematic it's difficult to see all the moving parts.
What really decided it for me was that the pricing I was seeing for the repair parts were nearly as much as a replacement so I decided to just replace it and spend time going sailing rather than doing plumbing. ?

thats great you cover all the bases one could ... i just hate it when i check something out only to find i didn't check one little thing i would have done the same thing ....but i still have trouble replacing things i think should outlast me:cussing:

 

[quadrille38]

thats great you cover all the bases one could ... i just hate it when i check something out only to find i didn't check one little thing i would have done the same thing ....but i still have trouble replacing things i think should outlast me:cussing:

Oh I so hear ya on that.

 

[Stu Jackson]

....but i still have trouble replacing things i think should outlast me:cussing:

Woody, the longer you have your boat, the more this will occur. Simple logic. I hear ya, since I have had these same thoughts a lot more often recently, too.

Two choices:

1. ignore it completely :Liar:

2. keep buying new stuff and putting it in and in a short time you will have a brand new boat!

Easy for me to say: new::: water heater and hoses, macerator pump, exhaust hose from muffler, all sorts of engine goodies - rw pump, alternator, alternator alignment, belt; all beyond the "standard" and routine maintenance. And I'm working on the To Do list which includes a new muffler i got from a very nice skipper here on this forum.

Enjoy.

 

[Jake N Eggs]

Well I got back to the boat and confirmed it is the same model valve and of course when you look it up on the Watts web site it says its a discontinued model and there is no schematic.

Not to be discouraged I took it apart anyway. Got it all apart, cleaned thoroughly and still not getting flow. Suspect there is a clog somewhere that I can't see or reach. Gave up and ordered a new one. Pricey little things at $71.00.

I had a problem with mine a few years ago and did the same as you, I disassembled the unit, couldn't see anything wrong, reassembled it and the flow was still low. I played hockey with a guy that works for Watts and he got me a new valve and a rebuild kit.

I took the valve off again with the intention of changing it and then found the plastic screen in the hot intake to the valve. It was clogged. I cleaned the screen and reinstalled the original valve. The flow issue was resolved. I now have a new valve and a repair kit as spares.

The repair kit came with the attached information. The screen is in the fitting just to the right of where it says Hot on the exploded view. There is also a screen in the cold intake but mine was totally clean.

Hope this helps.

 

[quadrille38]

I had a problem with mine a few years ago and did the same as you, I disassembled the unit, couldn't see anything wrong, reassembled it and the flow was still low. I played hockey with a guy that works for Watts and he got me a new valve and a rebuild kit. I took the valve off again with the intention of changing it and then found the plastic screen in the hot intake to the valve. It was clogged. I cleaned the screen and reinstalled the original valve. The flow issue was resolved. I now have a new valve and a repair kit as spares. The repair kit came with the attached information. The screen is in the fitting just to the right of where it says Hot on the exploded view. There is also a screen in the cold intake but mine was totally clean. Hope this helps.

I wondered if that might be the case.
You mentioned an attachment but it didn't show up. Can you retry posting it as I'm sure others could use it. Or can you PM me and attach it there.

 

[Jake N Eggs]

I wondered if that might be the case.
You mentioned an attachment but it didn't show up. Can you retry posting it as I'm sure others could use it. Or can you PM me and attach it there.

The attachment is the PDF document. If you click on it, it will open with Adobe Reader.

 

[quadrille38]

The attachment is the PDF document. If you click on it, it will open with Adobe Reader.

The PDF isn't showing up. I even tried logging in directly without using the ipad app and it's not showing there either.

 

[quadrille38]

The PDF isn't showing up. I even tried logging in directly without using the ipad app and it's not showing there either.

To close the loop on this, I replaced the mixer valve and the flow is perfect. Once I had new on I completely tore the old one apart as found where the clogs were.
Will be way more prepared next time and know exactly how to fix it.

 

[danstanford]

I would check the hot water line from the tank. I would think that there is some sort of a kink in the line. You can easily disconnect the line at each fixture but if it is at each fixture that is probably not the issue.

I have the same problem but only at the galley sink. All the other hot water outlets have good pressure but the sink has very low flow. I noted the same thing last fall at two locations on the cold side (all good now with no changes) so does it make sense that I have an obstruction in that line only?

 

[danstanford]

For anyone else struggling with this problem, I removed the lines one at a time and blew back through from the faucet to find out which one was going to the galley. The line ended up un-plugged but I reached my finger back into the tee fitting where the line terminated and pulled out what seemed like a piece of black rubber (like a scrunched up o-ring) jamming it up. Removing this solved the water flow problem.
Interestingly, Once I got the heater element reset pushed she started making hot water but soon the pressure/heat relief valve opened and she started spitting out water from that valve. Once I pulled it out I headed to the boat supply store where they suggested I go to Canadian Tire (automotive department store) where I found the exact match on the wall for $ 18.00. All back and running well now! Thought I would share the valve part in particular for someone who is struggling with the problem of the water heater releasing water into the bilge as soon as things get hot as they were when we were motoring as well.
Dan

 

[TFlight]

Nick -

I have a 2007 H36 and had the exact same issue In the spring.

The culprit was the thermostatic mixing valve. Some crud had accumulated on the input screens for it - I disassembled the connections to it (didn't take the valve guts apart !) - there were fine metal mesh screens that had crud on them.......cleaned screens, put it back together, and presto - lots of hot water flow again.

Hope this helps you!

Paul

Historical forums what a great thing! This post dated back to 2013 certainly did the trick for me.
I have a 2007 H 41 DS and at start up of season 2018 I noticed a drop in hot water pressure and a further decrease again this year now down to a trickle. Thanks for posting PKFK. I didn’t know there were screens in the mixing valve, but it make since to protect the valve, and that was the problem. From the looks of the screens (only 2 screens hot & cold inputs not on the mixed hot water out) and orifice I’m surprised I was getting any hot water at all. I cleaned out all the debris and presto I have hot water pressure again.

P.S. On this model valve once you loosen and back off the coupling there is a good chance the screen will drop out and some how find the most difficult to reach part of your bilge.

I’ll try and attach some pictures of the mixing valve, screen and it’s assembly.