Editor’s note: This article also will appear as an open letter to HVAC contractors in The News , a trade publication serving that industry. We hope to receive a response-in-kind from the HVAC perspective.
When bidding earth-coupled heat pumps, heat-exchanger design usually is one of
the first steps. There are many choices – horizontal loops, pond loops,
vertical loops, open loops, etc. These choices usually are site-specific, with
no two jobs being exactly alike. If the best choice is vertical loops, your
system probably just became more efficient, and your life, more complicated.
Vertical lops are going to require a hole in the ground, and for that, you are
going to need a driller. This is where I’ve seen more problems than all the
other aspects of the job, and I’ve been involved with this industry for more
than 40 years. The reason: Two very different sets of skills and equipment are
required to accomplish this. Think of the football star and the guy who makes
his shoes. They have to work together to achieve success, but neither has a
good handle on what the other does. Oh, they think they do. The shoe guy
watches every Sunday, and, by his own admission, knows more than that dumb
quarterback who just threw six interceptions in a row. The quarterback figures
that anybody could make a decent pair of cleats a lot cheaper than the highway
robbery he just paid for his. They both are wrong. As I said, it takes two
completely different skill sets to win the game.
When hiring a driller, I have a few suggestions that can make the job go a lot
First, just as the selection of vertical loops, drilling is site-specific.
There is no drilling method that will work everywhere. What works on the coast
won’t work in the mountains, and vice-versa. Find a driller who knows the
drilling conditions at your location. Sometimes, drilling conditions can change
from one end of the project to the other. Usually the drillers in closest
proximity to the project are a good place to start. Or, if the property has a
well on it, find out who drilled that well and talk to him, as he will have a
better feel for the conditions than anybody else.
If you can’t find a driller who knows the location well, you may be ahead to
hire a driller to drill a test hole. This may or may not be a useable hole for
your project, but it will allow the driller to give you a fair bid for his
work. Without a test hole, he may be shooting in the dark, and give you a price
that either is too high or too low – either way, one of you is not going to be
happy. If you go this route, pay the driller for the test hole separately from
the rest of the project, and adjust the price. The price for the project might
stay the same, or it might be higher or lower, due to conditions the driller
finds on the job.
Next, certification. Most HVAC contractors who install earth-coupled heat pumps
are IGSHP-certified, or should be. They often think the driller should be as
well. I’ll let you in on a secret about driller’s certification. Until
recently, the driller went to the same class you did. He heard all about BTUs,
mass airflow, thermal transfer and I don’t know what all, but most of it had
nothing to do with drilling. Most of the drillers I’ve talked to will admit
sleeping through a lot of it, and coming away with the skills to check the
breaker if their heat pump quit. After that, they learned enough to call
somebody who knew what to do.
There now are certifications that are geared more toward the driller, but not
many drillers have been through it yet, so I don’t think certification should
be at the top of your list of qualifications. Some of the most productive – and
successful – loop installers are not certified.
Cost: Be prepared for it. On a lot of projects, the cost of drilling and loop
installation may be well over half of the total bid. It may come as quite a
shock to the HVAC contractor, who never thought about the equipment costs,
labor costs and skill set needed to drill a hole in the ground.
Unfortunately, I’ve seen many an HVAC contractor totally freak out at the cost
of drilling. Suddenly, they come to an idea that is best explained by
consumption of large amounts of whiskey: They decide they can buy a rig and
drill those holes for nothing, and not have to pay that highway robber who
happens to own a rig. How hard can it be? After all, that driller just stands
there in the mud, raking in all sorts of vast riches. Doesn’t even know enough
to go in out of the rain, for cryin‘ out loud. Kinda like the quarterback and
It doesn’t bother those of us in the drilling industry all that much, because
we know where this is headed. Here’s the scenario: First, the HVAC contractor
gets sold a brand-new rig that may or may not be suitable for the purpose.
Next, he gets on location and finds out that there are all sorts of other
necessary equipment that the rig salesman didn’t bother to mention – more money
and time spent. Then, the nice man from the government probably will show up to
ask about his driller’s license. Driller’s license? “I’m not drilling a well.” “No,
but you are making a hole in the same ground that my drinking water comes from
and I wanted it protected.” After that hurdle, you actually get to drill. Now
you are getting somewhere, saving money, getting the project back on schedule,
all that good stuff, until you lose circulation, stick the pipe, twist off or
lose the bit, or any number of problems drillers face and avoid every day. Now
The usual response – after an appropriate amount of cursing – is to throw more
money at the problem. I’ve actually seen contractors spend 6 weeks on a job
that should have been done in 2.5 days, rather than admit their mistake. This
is where the friendly local driller shows up, and offers to take that mess of
their hands. Some drillers have gotten some pretty good rigs for pennies on the
dollar that way.
In a nutshell: Hire the right driller, pay him fairly, and then get out of the
way. You’ll both be happier and more profitable.
One other note: On larger projects, you may need to hire more than one driller
to complete the project on time. In this case, you should consider hiring a
consultant well versed in drilling and loop installation to oversee the
drilling end of things. He can coordinate the materials, logistics and details
necessary for the job. There are many other facets to it, but this should give
you a starting point. If I can be of any help, e-mail me at
To Heat Pump Installers: Working with Drillers
June 1, 2009