DANGER OF THE WEEK AWARD

Bad Tenants

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This weeks award goes to all of the tenants who think that they can fix issues themselves as well as to highlight to landlords that if you don’t educate your tenants they WILL try and fix things for themselves. Case in point the boiler pictured below. The original complaint was that water was flowing out from the side of the building and that the boiler was to blame. In actual fact the scalding hot water was spilling out forty feet above the street and onto a loading dock below. The complaint came because the business owner had had enough. The cause of the problem was easy to spot once we saw the boiler.

The filling loop valve can be seen in a slightly open position which is how we found it. With the filling loop open the heating system is left with water continually flowing into it. Fortunately there is a route out for excessive water pressure in a heating system and that is out via a Pressure Relief Valve as shown in the third photo. The valve is set to mechanically open at three bar. It is there to make sure that if the pressure in the heating system rises too high the excessive pressure will be safely released.  The second photo taken at the same time shows that the pressure is too high and therefore the pressure relief valve IS open and venting hot water out onto the street below.

So in a carbon copy of an issue we repaired a few weeks ago. Everything pointed to the internal expansion vessel being damaged. In this case the internal bladder was damaged and the unit was full of water instead of nitrogen. We returned the next day with a replacement vessel and new pressure relief valve. We drained down the system and replaced the vessel. When we topped up the pressure however it just leaked away within a few seconds. The pressure relief valve was also faulty and we now had an understanding as to why the filling loop valve was left open just a little bit.

The thought process behind leaving the filling loop open just a crack is that if the pressure on the heating system is dropping too quickly (i.e. a few days) then leaving the valve open just a crack will keep topping up the heating circuit. IT DOESN’T WORK! In the end it always ends up over pressurising the system. Once the system is over pressurised above the three bar limit the pressure relief valve pops opens and lets excess pressure (and water) escape. The pressure relief valve then closes until the system over pressurises at which point it pops open ad infinitum.  The valve which is just a flat plat help closed by a spring then gets full of heating system nasties like grit, debris and sludge so that even when closed it won’t seal  properly thus allowing the pressure to escape continuously. It usually requires a replacement. Also it should be noted that as the pressure grows to three bar with the pressure relief valve still closed some radiators, valves and pipe work joints might start leaking as a by product of too much pressure. So even after repairing or replacing the damaged expansion vessel and pressure relief valve there may be other areas where water is leaking out or air is leaking in. The latter is VERY hard to find. So to end part one of this story we cleaned up, put the boiler covers back in place and then instructed the landlord and tenant on the proper use of the filling loop.

Two days later we get a call that the boiler is dead and now producing no heat or hot water. We head over to find that the boiler is again over pressurised as shown in photo five, the filling loop has been left open and the water, now cold, is spilling out via the pressure relief valve. Why? We can’t get the boiler to fire up either. As we start to troubleshoot the entire system we locate a ‘new’ problem. It’s new to us.  We find that the heating system timer has an intermittent  fault. Sometimes the heating comes on and sometimes it doesn’t. The tenant felt that the system wasn’t coming on because the pressure was to low so went ahead and left the filling loop valve open again! Of course it didn’t fix the problem. How could it?

In the end we repaired a bad contact plate in the timer and after bleeding away the excess pressure in the heating system everything fired up and worked correctly. We have now posted instructions on how to fill the boiler if required and a warning not to overfill. In a related note we have also changed the main fuse which was incorrectly installed as 13amp. Most residential heating systems will require only a 3amp fuse.

There are many lessons here for the landlord and tenant alike. Landlords needs to take steps to make sure that the tenant understands what they can do and what they CANNOT do. We always recommend an A4 sheet with instructions on how to set the boiler timer, how to turn off the main water stop cock, how to turn off the gas supply and how to turn off the power. Also, the instructions should also list such topics as what to do if the heating doesn’t work. For example if the red light on the boiler is flashing; don’t touch it and call the landlord. By doing this the tenant and your property are protected from dangerous or damaging events such as a broken water pipes or a gas leak as the tenant can turn off the services themselves.

The tenants too should not be playing with things they don’t understand. We’ve been to three this week where the tenants have damaged the heating system by trying to fix it themselves. A god example was a tenant who mistakenly turned off the heating flow pipe isolator while trying to use the integrated filling loop to increase the boiler pressure. The problem started last month and after repeatedly trying to sort it out themselves they finally called the landlord who called us. The original issue of low pressure was sorted in minutes but the second issue of the boiler overheating too fast took a bit longer. Everything pointed to a plugged up heating pipe or in this case a closed heating pipe. In the end the tenant caused their own problem of having no heat for weeks but also being afraid to call for help.

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