All the water outlets in my condo can only supply hot water for at most 2 mins and then I am left with cold water. I changed my gas water heater 2 days ago, but the problem continues. I was desperate when I thought the problem was finally resolved but was left with cold water again during a shower. Do anybody happen to know what is going on here ? Thank you a lot.
Hoping someone can give me some thoughts on what might be going on here so I can be a bit more informed when I call a plumber.  Situation is, we got our water heater replaced a few years back and ever since this has been an issue. It's more noticeable when it's cold outside it seems, but still seems to be a year round problem. Whenever we  use hot water, we basically run out of it within minutes. In order to get an acceptable amount of hot water (enough to take a 10 minute shower), we literally have to prime the water first. By that I mean I have to turn on the hot water, let it run for a couple of minutes, then turn it off and wait 20 minutes. Then when we go to use the hot water again we'll get hot water for a respectable amount of time. Now I am fairly ignorant to all this, but it seems a 71 gallon hot water heater should be capable of holding enough water to not need to be primed like this. I should be able to take a 30 minute shower, let alone 10 without running out. My shower this morning was decently warm for maybe 2 minutes before it was just warm-ish.   So if anyone can give me some ideas on what might be going on I would appreciate it. We've just put up with this for some years assuming perhaps it was some eco friendly thing. Like the system doesn't maintain much hot water in the tank so it's not always running and only heats water up when you start to use it? I hope that isn't the case though and even so, I should be able to get more hot water out of it. Any help?  UPDATE Sorry everyone, I meant to tell you all that the water heater was gas. The pilot light is lit. I don't recall the specific model though I can look that up if people think it will help. I have actually turned up the thermostat on it above the default and when the water heater is putting out hot water, it can be very hot. Too hot. But again, that requires us to prime it before we get any decent amount of hot water out.  UPDATE 2 Looked it up, I believe this is the model info if that helps anyone: State Select: High Output. Model number: GS675XRRS 300
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It will eventually be driven by a Visualforce component, which will be configured by querystring parameters in the URL.  I just ran into an issue where the query fails when I use dotted bind variables.  If I copy the constructed dynamic SOQL into a static query, it works fine.  This may be a bug, because in doing tests I found that :foo.bar would actually try to use local variable bar.  Here's one of my queries, which uses related custom objects.  I've stripped it down to just the part that's failing (wrapped for legibility):  result = Database.query('SELECT Name, Another_Object__r.Name,      Another_Object__r.Custom_Field__c      FROM Custom_Object__c       WHERE Another_Object__r.Custom_Field__c = :filter.deviceType');   The error reported is System.QueryException: Variable does not exist: filter.deviceType.  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