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Shower valve/cartridge problem or frozen pipes?

Posted by loves2read (My Page) on
Thu, Feb 3, 11 at 2:46

Trying to decide if master shower has problem with valve/cartridge or maybe ice in pipes...

Have a shower in master bath with 3 shower heads--rainshower from ceiling and two regular ones on adjacent/90 degree husband tried to take shower and got reduced flow from any shower head...

Our temps past 3 days have been 20 and below because of ice storm in DFW TX area.
Part of plumbing for this shower runs through the attic because the original owners had line going to that shower freeze the first winter they owned home--7 or 8 yrs ago.
WE had the mixing cartridge in the main two-lever Moen valve to seize up and require replacing right after we moved in two years ago.

So we thought it could be either/or situation...husband went into attic could not see problem with cracked pipes...
all other water sources are running with full pressure/hot or cold--up or downstairs...

We have home warranty policy that covers plumbing--called company--they gave me plumber that will handle the call--problem is plumber is not making calls because of freezing weather/icy road conditions...Answering service says that plumbers will come in Thursday and check their calls and let me know when they will come out....
Call the warrenty company back since there is NO real guaranty of when plumber will be out but because there is no evidence of secondary damage--like water leaking from under a wall-- or "emergency" like the only toilet is blocked--we have to wait at least until I get response from assigned plumber.

I just want to know if we should continue to run low flow of water from the shower heads in case there is partially frozen line or if doing that will cause damage if it is bad valve...I managed to move the contols around today and get good water flow to two heads once--but could not duplicate it when I turned the valves off and tried to open it again...can only get minimal flows now.

So what are the odds that this is second problem with the main valve --there are two for the 3 heads-- with one feeding off the main valve

or that we could have some ice blocking the line even with water running through the lines all day...High got to 19 today...tonight will be down to 7 I think--

This house has recirculating hot water system (two water heaters in attic linked together)Not sure how that affects how many faucets to keep open. But the hot water is working fine any other place.

Probably too much info--appreciate any advice--not sure we will get plumber out Thursday even--and frankly would just as soon NOT have to run the water if we don't have to. I know some of it is running from hot water heater which will just make it burn more gas to heat it.

Here is a link that might be useful: This is line drawing of what the Moen valve looks like

Follow-Up Postings:

RE: Shower valve/cartridge problem or frozen pipes?

Actually, letting the water run might save it from freezing throughout and bursting. In addition, you should be trying to thaw those pipes in the attic as soon as possible. Forget waiting for the plumber since it could be too late if it bursts.


Also, to get you through, buy a roll of heat tape and run it along the supply pipes up there. Plug it in asap.

RE: Shower valve/cartridge problem or frozen pipes?

Never too much information when describing a problem. I agree with homebound. Adding to his post. Do get up there with the roll of heat tape, approx $20 at Home Depot, asap. Should the pipes burst, you'll have to turn the water off at the main. No water to the house, no toilets, and damaged sheetrock along with possible mold and moisture problems later. Also, re his comment about leaving the water running. Yep. However he didn't mention volume. I believe it doesn't have to be running at full force. (Homebound, correct me if I'm wrong.) I believe a little more than drip, a small steady steam so to say should be sufficient to keep the water running and transferring warmer water through the pipes. It should stream in such a way that it doesn't break into droplets when it hits the tub. For the DIYer's, a way to test a cartridge is to remove it. Have a partner (connected via cell phone) in the basement while you remain at the tub. Have them turn it on and watch the pressure from the rough in w/o the cartridge. If it is still restricted, then the pipes are freezing. If not, then the cartridge is at fault. Most manufactures offer lifetime warranties and will ship a free cartridge. Replace the old with the new since you have the old one out anyway. If the old one was good, save it for a later emergency.

RE: Shower valve/cartridge problem or frozen pipes?

My husband and I both now think this problem in shower is really a valve/cartridge problem...

the plumber is not coming out until Monday --
the company said that they were not required to come out sooner because 1--the weather is still under 32 and apparently this plumbing co will not check frozen pipes when it is still freezing (unlike some others -- I know that is a jacked-up attitude) and 2-- we don't really HAVE an emergency since we have another shower to use and there is no evidence of secondary damage occurring--

frankly I think that is because we are using our home warrenty contract to cover this call and they know they can't jack up our rates --

We have no basement--house is in DFW TX area--homes here (unless they are built on sloping lot with serious elevation change)almost never have basements...

We still have no prblem w/water flow in any bathroom except for this shower--
but we are letting it drip again tonight--and a sink faucet on an exterior wall...(just to humor me more than anything)

Do either of you know if having a re-circulating HW system so that you get "instant" hot water when you turn on that tap makes a difference when you are trying to prevent freezing pipes--
I don't know how these plumbing lines are run for that system--and I have read there are couple of ways to design/install one...

RE: Shower valve/cartridge problem or frozen pipes?

If you think it's really cartridge-related, sure, wait until Monday. But if it can be due to freezing in the pipe serving that bathroom, or the valve itself, you had better act pronto. Exposed pipe in the attic (in extended freezing ocnditions), or that's outside of the insulation in the wall, will be a major emergency if it bursts.

Recirculators "may" help, but the cold line may not get enough circulation. I wouldn't rely on that.

RE: Shower valve/cartridge problem or frozen pipes?

It's probably cartridge related. If your pipes are partly frozen, as soon as you run the water the ice will melt and normal flow will resume within a short time (15-30 seconds).

I would guess cartridge, which may simply need a cleaning.

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