I rent an apartment in a high-rise building in Australia, and my shower is giving me trouble. When I shower at 6:00 am, the shower functions normally. However when I wake up late on the weekend (while everyone else in the building is doing their laundry, etc), the temperature fluctuates constantly from cold to scalding. My shower is controlled by a single knob that twists for temperature, and lifts for flow volume.
I spoke with my building’s manager about it and he said that the problem is the water heaters. They’re built into the walls and provide a boost of heat. At least one is malfunctioning, but it’s inaccessible as there are no access panels for them.
What I’m wondering is:
I think there is a “flow control valve” or “mixing valve” or something in my shower behind the knob in the wall. I think it’s job is to keep the temperature constant. Does this device exist and if so, what is it called?
Are the problems I’m experiencing indicative of a faulty “flow control knob”?
Do inaccessible, in-wall water heaters exist, and could they also cause problems like mine?
The mixing valve mixes water from the cold water supply with water from the hot water supply. The mixing valve’s job is only to take some water from this pipe and some from that pipe depending on where you turn the knob. It can’t do anything beyond that. Some showers have, behind the mixing valve, an anti scald valve. What this does is (assuming it isn’t battery powered and actually sensing the temp) watch for drops or spikes in flow on one side and match it on the other side. This way the mixing valve is always getting the same (or close to it) flow from both sides. It’s actually a very simple and ingenious little mechanism.
Probably not, but it’s hard to say. Most likely, it’s exactly what you think it is. Everyone using the water at once.
I have no idea what it’s like down under. But I can’t imagine having something like an inaccessible water heater would be up to code in the states.
Sounds to me like a landlord that doesn’t feel like fixing something.
Thank you for your advice! I’m really glad to have the correct names for these valves.
I know that in my old apartment, if you flushed a toilet while the shower was running, no temperature change occurred, so my understanding is that the anti-scald valve prevented the drop in pressure in cold water from causing the hot water to take over. Could it be that there is no anti-scald valve in my new shower, or that it is stuck with minerals from the water? For what it’s worth, this apartment building is pretty new.
I just don’t understand how a faulty water heater could cause fluctuations in temperature. Sure, the temperature could be higher or lower than expected, but why would it go up and down repeatedly in the span of a 5 minute shower?
I’ve been trying to dig up plumbing codes for my area and I’ve found that “tempering devices” are required on all new buildings, but I’m not sure for how long that rule has been in effect. I think the odds are that my shower has one…Maybe it’s broken? Maybe it’s something else that I don’t understand.
Google temptrol shower valve, I have one of these, they auto adjust the flow to keep a steady temperature. So once you set it to the temperature you desire it will stay there, if there is a pressure loss on the cold side (a toilet flush) the valve auto drops the pressure on the hot side to compensate thus keeping an even shower temperature…
I doubt if you have a hidden in the wall water heater. That would be a bad idea.
If you have a hot water booster heater they can be instant water heaters. And if the stat goes out on them then they will turn on and off with a high limit switch. The high limit can have a large range between on and off.
You say high rise, how high?
You should be able to get a pressure gage at a hardware store. There are the type that you remove the areator from a sink faucet. check the pressures through out the day, see of it changes by much.
Maybe I misunderstood what the Building Manager said. maybe he was referring to a hot water booster as you say.
The building has 7 stories, each with 7 apartments. (And each apartment has 7 spiders, all of which are missing one leg. If spider shoes cost…)
I can look into getting a pressure gage, but what would it tell me? Would it be that if the pressure varies wildly, then it’s probably a problem with the anti-scalding valve, but if the pressure is steady than it could be the hot water booster?
I need to nitpick my post. When I said “anti Scald” valve, what I meant was balancing valve. What a balancing valve does is exactly what I said, it keeps everything balanced.
An anti scald valve is different in that it has a user adjustable setting that only allows you to turn the knob so far in the hot direction.
If the pressure is all over the place, it’s a pressure issue. It could be a bad booster, or could just be that the whole complex is trying to use the water at the same time and the best way to deal with it is to get up an hour earlier or shower an hour later.
If the pressure is steady, it could be what the landlord said. A bad water heater. Everyone is using the water at once at the water heater(s) can’t keep up. With one down they’re really struggling. It wouldn’t be an anti-scald device, but the diaphragm in the balancing valve could be sticking (sorry, my fault). Though, unless you have hard water, I’d expect that to take years to happen, but it could be possible.
Personally, I wouldn’t worry about the gauge. What are you going to do with the results. You’ve made your complaint. You were basically brushed off. Going back to the landlord with data isn’t going to get him to fix the problem. He seems to know what the problem is. I think your best bet is going to be to ask him once in a while when he’s going to get around to fix it. Or, what I usually suggest, ask the neighbors if they have problems. If they do, tell them to complain also.
You seem to say that it could be the building’s booster/water heater no matter what I measure with a pressure gage. That’s too bad; I was hoping to be able to tell the Building Manager something definitive.
That being the case, I guess I’ll have to agree with you. The best course of action is just to be a pain in his side until he fixes it.