Wirsbo PEX question

[jam99]

Hi.

Newbie here looking for some advice.
I have copper pipes running off of my hot water heater that connect to Wirsbo aquapex plastic hosing. There is a cut off valve that is wide open before the Wirsbo connects to a spot where one hose goes upstairs to my kitchen sink (running great with good hot water pressure) and the other hose heads upstairs to my bathroom. The hot water pressure in my upstairs bathroom is horrible. I have a 2 handle faucet system in my bathroom sink and the hot water pressure is 10% of the cold water. In the shower, I can only have a decent hot shower for less than 5 minutes before the water turns cool and I can't turn the one handle system any more left to make it hotter. When this happened I checked my kitchen sink to see if I was indeed out of hot water but it was fine (I ran straight hot water for 5 minutes and it was still very hot).
This Wirsbo hosing is new to me (just moved into this house) and I'm at a loss as to what steps to take to try to fix this.
Any suggestions or tips would be greatly appreciated.
Thanks.

[jadnashua]

One of your valves may have a cross-over leak which lets the hot-cold interchange. This will make the hot line warm as well as the cold one, and limit how hot things can get elsewhere in the house. As to the hot volume, that hose may have a kink in it or that valve may have a screen filter on it's inlet that is plugged.

All modern anti-scald valves have a max temp adjustment to them...yours may be set incorrectly. This adjustment might be a screw, a cam, a piece of plastic with notches pushed into the handle, etc. Its whole purpose is to limit hot hot the valve can get - you may need to adjust that.

[jam99]

Hi Jim.

Thanks for the response.
I don't think its an issue of cross-over leak, but it could be the screen filter being plugged?
I've tracked the line as my basement ceiling is open and I can't see a kink. Is the screen filter something that I'm going to be able to access to be able to clear or is there a way of flushing it? There's one line that comes off of the hot water tank (copper to Wirsbo) that then has a t in it that goes to my kitchen sink and to my bathroom. The kitchen sink is fine (lots of hot water and good pressure) but both my hot water taps in the bathroom are low (sink and shower). The connections seem to be cinched tight and I'm not sure that I should be undoing them to check for a clog?

[jadnashua]

Not all shower valves have a filter screen...would need to know the brand and model. A vanity faucet usually has an aerator, and it could be clogged. It may also have filter screens, or, the cartridges could be clogged.

If you can find a parts diagram, it would normally show if there's a filter screen. From that, you could also figure out how to take it apart (assuming you're handy).

What size is the pex you ran? Keep in mind that the ID of pex is smaller than copper, so you're flow could be compromised, but it should be plenty to feed either one showerhead or the vanity, since both of them are flow restricted (at least in the USA). 1/2" pex is closer to 3/8" copper than it is to 1/2" copper. The vanity faucet is normally limited to about 2gpm, and a showerhead at 2.5gpm in the USA. Canada may or may not adhere to this or some other spec. The tub filler, though, is unrestricted (except by internal design, not the government), and with a 1/2" line, you might see 6-7gpm of mixed hot/cold, less with only one or the other.

[hj]

The type of faucet you have in the shower will determine whether there COULD be crossover, but even if there were it would usually affect the OTHER faucets in the room, not the tub/shower. There are other possible causes such as, Do you have a recirculation pump at the water heater? If so, that can cause your symptoms.