By Mike Holmes, owner of Holmes Heating & Air Conditioning in Denver Colorado.
An ounce of prevention is worth a pound of cure, right? Let me share a lesson I learned the hard way.
I had recently completed a radiant heating system in a new construction home. It consisted of an Aspen condensing boiler, buffer tank, ECM pumps and a variety of in-floor zones. I fired the boiler, analyzed the combustion, watched the system heat up and go through its paces, and left the mechanical room spotless.
A few weeks go by and the general contractor calls me to say that the system is not heating. So I left to go look into the issue. On this particular morning it was -8°F. I arrived to find the mechanical room being used as a dumpster.
Investigating the issue
The valve caps were removed on the boiler drain, near-boiler piping low point drain, several of the radiant loops, and there was a short hose on the buffer tank drain. I had installed a bunch of Webstone isolation valves with purge ports. This was a bad sign, but the actual issue didn’t dawn on me immediately. It didn’t take long.
The buffer tank was empty and so was the boiler and primary heating loop. Several of the radiant loops were dry, especially those on the second and third floor. By my assessment, another subcontractor tried to get water out of the system to fill buckets to mix mortar or grout. They started on the radiant loops, then went to the primary loop, and hit the jackpot when they tapped the buffer tank.
I couldn’t figure out A) why they would go to the boiler room for water when there was a hose bib nearby and B) why the boiler’s autofill valve had not at least been trying to keep up with the water loss. Then I realized that the water to the home had been shut off for some reason or another.
I spoke with the tile installer, and he said it must’ve been the stone mason. I never found out for sure who the culprit was, but either way, I spent the next two hours purging the system. Luckily everything fired up perfectly and the general contractor said he’s going to install a lock on the boiler room door.
Labels = Cheap Insurance
The lesson learned was to always label drain valves. If possible, lock the mechanical room door.
It seems excessive to label every single drain on a mechanical system, but I think I’ll start doing it on new construction jobs where other subs have access to the boiler room. I know installers who take all the handles off of their valves, but that’s still not full-proof to a motivated person who has a pair of pliers and is unaware of what they are doing.
If the mechanical room has a door, hang a sign on the door explaining that the valves inside the room must not be opened. Make sure to list this in English, Spanish, and any other language that may be prevalent among the trades in your area. If there’s no door, hang it on the system pipes, maybe in more than one location. Print these signs on bright paper. Make them unavoidable.
As an additional layer of protection, you can hang customizable tags on each valve. This company makes all variety of custom valve tags in several material options. They start around $2.00 each. That’s cheap insurance.
Keep in mind that not everyone on a jobsite understands the interconnected components in a mechanical room. Unfortunately, this can lead to subs tapping into the system for their perceived convenience. Ultimately, you, the general contractor and the homeowner will pay the price.