#34 Part 2: Who is the DHW Recirculation Detective of Denver? (spoiler alert, it is Mark Eatherton)

DHW recirculation systems can cause a lot of headaches, if not operating properly.  Quick troubleshooting is essential, especially in the multi-family sector.  How do you know what needs to be fixed?  What questions do you need to ask occupants and building managers?  Are all shower valves the same? Do you need x-ray vision?  

In this two-part episode, the guys interview Mark Eatheton.  Mark is a licensed Master Plumber in Colorado and an ICC licensed Master Mechanical Contractor.  He has worked on a variety of troublesome, multi-family DHW recirculation projects over the years and offers his advice to avoid pulling your hair out.  Mark and the team at Advanced Hydronics have worked with Energy Outreach Colorado to reduce energy usage and water waste in many projects across the state.  Starting with occupant surveys, they determine what bothers the residents.  After that, Mark describes the symptoms to look for throughout the building.  To finish, he describes the best path forward with specific control components.  

Thanks for joining us today.

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Transcript

0:04
welcome to ask a caleffi the podcast that
0:07
dives into real life problems that
0:09
plumbing and hvac technicians face in
0:12
the field we're your hosts from the
0:13
caleffi tech support team i'm greg tubbs
0:16
and i'm dan ferkus welcome we look
0:18
forward to sharing some stories from our
0:20
tech calls and using our background and
0:22
expertise to make your days a little
0:24
easier
0:25
[Music]
0:29
hey there welcome back to the ask caleffi
0:31
podcast today we're going to pick up
0:33
where we kind of left off in a part two
0:36
of this episode with mark etherton where
0:38
we're going to discuss
0:40
the issues that we find in domestic hot
0:42
water research systems well and your
0:44
technicians in the field i'm sure really
0:47
appreciate the amount of upfront work
0:50
that you do in investigating the
0:51
projects before you're sending them in
0:53
you know i can they do i can imagine
0:55
being you know a service being one of
0:57
your service tax and going into a a
1:00
problem job and
1:02
you know being looked at like you know
1:04
it's a problem you created because not
1:05
enough due diligence and preparation
1:07
went in on the front end
1:09
to make the corrections so that your
1:12
project is successful yeah they they uh
1:15
they stop you and they go nobody else
1:16
has ever asked you these questions
1:18
before well number one they probably
1:20
didn't know that they were supposed to
1:21
be asking that questions because they're
1:23
looking for a quote-unquote problem
1:25
right and you know they're they're quick
1:27
easy fix as well as put in a bigger pump
1:31
you know that's that's not always the
1:32
solution
1:33
seems to always seem to always be their
1:35
first attempt but not always the
1:37
solution first attempt in the first and
1:39
the first thing to cause a problem down
1:41
the road with erosion corrosion sure
1:43
that's what they know how to do yeah you
1:45
know that's that's the easy fix in their
1:47
eyes as well let's put a rigger pump on
1:48
there and see what happens
1:50
and that's the problem is they can't
1:52
quote unquote see what's happening right
1:54
and uh you know the complaints may
1:56
subside a little bit but the problems
1:58
are still there and the only way to
1:59
address it correctly is to go through
2:01
and thoroughly balance the system out
2:03
eliminate any cross connections
2:05
eliminating any backflow occurring
2:07
within a system
2:08
and uh basically set it up so that it's
2:10
going to work like it's supposed to yeah
2:13
yeah i know there's a lot of systems
2:14
that aren't balanced at all or it's
2:16
definitely not balanced properly
2:19
but i also believe there's probably a
2:21
lot of cross connections out there that
2:23
aren't discovered
2:25
well there is and some of them were
2:27
inadvertently set up i had a call this
2:29
last week from one of our manufacturer
2:32
reps
2:33
and he says i've got a prison
2:35
that they are unable to get
2:37
hot water to their showers he said all
2:39
the showers in one place
2:41
and he said but i think i may have
2:42
discovered what it is because he had
2:44
attended one of the caleffi seminars that
2:46
i had spoken at okay and he said they've
2:49
got all of these
2:51
mop sinks
2:52
that have a chemical mixing station on
2:54
them there it is where the hot and the
2:55
cold water come together to a common
2:57
point mixed down goes through picks up
3:00
soap goes into the bucket
3:01
and i said are there check valves and a
3:03
cold hot water supply and he said i
3:04
don't think so and i said you just
3:06
discovered your cross connection i said
3:08
have them close at least the hot or the
3:10
cold water valve on every one of those
3:11
valves and see if hot water restored
3:13
up to showers
3:14
and i have not heard from him so my
3:16
assumption is yep that's where it was
3:18
and that took care of it because it
3:19
happened it had been calling back going
3:21
well no that didn't work right yeah
3:23
what's the next step there yeah we had
3:25
we had an interesting tech call come in
3:28
um from a local project to us here in
3:30
wisconsin and it was a hotel
3:33
and they have one of our legio mix
3:34
electronic mixing valves on site and
3:37
it's been in it's been working perfectly
3:39
they've had you know no hot water
3:42
complaints or issues and suddenly the
3:44
contractor got a call of you know no hot
3:47
water or low temperature hot water and
3:50
then the next day he got a call again
3:52
and
3:54
they were determining what we were able
3:56
to do because our legio mix has
3:59
data logging yeah it it stores the
4:01
temperature histories you know we're
4:03
able to walk him through that and what
4:05
we determined is every
4:07
it was occurring at six pm and it would
4:10
occur for two hours two hours spread
4:13
around 6 a.m or sorry 6 p.m every day
4:16
and they were determining they
4:18
determined that's when the maintenance
4:19
crews were in there or the cleaning
4:21
crews were in there and they found a
4:22
crop were able to find a cross
4:23
connection because of that but the data
4:26
logging feature in our legio mix
4:28
electronic mixing valve help discover
4:30
that
4:31
yeah
4:32
yeah exactly and that's that's where
4:34
data loggers are indispensable and you
4:38
can't be there every minute of every day
4:41
but if you leave a data logger there
4:42
that takes a snapshot every minute then
4:45
you get a really good idea of what's
4:46
going on what the trends are and then
4:49
you know as you said listen talk you
4:51
know what happens at six o'clock oh
4:53
before i mean it's cruz go ahead and
4:54
start working in the hallways
4:56
yep
4:57
that's what they related to that yeah
4:59
it's fantastic
5:02
but yeah it's you know there's not too
5:04
much information that you can gather and
5:06
the more information you have
5:08
the more accurate you're going to be in
5:10
going and making recommendations i mean
5:12
we don't only recommend the use of the
5:14
series 116 we also use the the quick
5:16
flow service
5:18
you know if you've got a split in the
5:19
branch of the hot power supply main then
5:21
you're going to have a split in the
5:21
branches coming back and you want to
5:23
make sure that you keep the water
5:25
velocity within that pipe below an
5:26
erosive velocity and the only way that
5:29
you can do that is to see
5:31
literally what the gallons per minute
5:32
movement is sure
5:35
so mark
5:37
what are your top three issues that you
5:39
run into in the field
5:42
uh usually the top three complaints that
5:45
we get are shortages of hot water that
5:47
are time based and when you start
5:50
looking at what's occurring as it
5:51
pertains to
5:52
the load and the source of supply
5:56
again due diligence requires us to do a
5:58
load calculation not just for space
6:00
heating
6:01
but also for domestic hot water
6:03
and in sizing the domestic hot water
6:05
heating system if the boiler is too
6:07
small or the storage tank is too small
6:09
or the shower heads are flowing at a
6:11
rate that's excessive
6:13
then that will create a shortage of hot
6:15
water during peak demand conditions
6:17
and it's usually quick to recover as
6:19
long as people quit using hot water but
6:21
if the load calculations say you need
6:23
400 000 btus per hour and 120 gallons of
6:26
storage and you've got 200 000 btus and
6:30
80 gallons worth of storage
6:32
well there's your problems journey right
6:33
in the phrase right it's not a physical
6:35
plant problem it's a physical allocation
6:38
problem so you've got to do due
6:39
diligence on that side first few sources
6:42
capable of generating hot water
6:44
necessary to handle the loads
6:46
as it pertains to loads loads vary by
6:48
use
6:49
uh you get into an apartment complex
6:51
where people are working regular jobs
6:53
peak demand is going to be between six
6:55
and eight am in the morning
6:57
and then there will be another peak
6:58
command between four and six pm in the
7:00
afternoon when they return
7:01
and then there's a little spike lunch
7:03
when people are washing dishes
7:05
when you start looking at like senior
7:07
housing facilities
7:08
there is no demand unless there's a
7:10
bingo bus that night which case there
7:12
will be a demand right in most cases
7:15
they're randomly using hot water
7:17
throughout the day they don't shower on
7:18
a daily basis they don't have to work up
7:20
to go to work so there is no six day a
7:22
demand
7:23
but you have to look at the system as a
7:25
whole it's used make sure that
7:28
the necessary to use capacity plus the
7:30
storage to take capacity and that the
7:33
shower heads are not access it i've seen
7:35
our head flow rates in
7:37
six gallons per minute in some of these
7:38
little buildings
7:40
uh we're supposed to be at two and a
7:41
half gallons per minute right so our
7:43
recommendation at that point would be
7:45
number one absolutely as soon as
7:47
possible
7:48
replace all of these high flow tower
7:50
heads with a look low shower head
7:52
and a lot of problems with the weight
7:54
and a lot of problems that are
7:55
associated with uh hot water shortages
7:58
are usually addressed by somebody coming
8:00
in and putting in a high flow rate or
8:02
taking a restrictive orifice out of a
8:04
jar head which just compounds problem
8:07
again they're not looking at the problem
8:09
as a whole they're looking at that
8:11
minutiae problem within that unit itself
8:14
and thinking well if i put in a bigger
8:15
headline and more outlaw the complaint
8:17
should go away
8:18
oh yeah that will create a complaint
8:20
somewhere else down the line yeah
8:22
it does
8:23
yeah
8:24
absolutely dutch boy putting his finger
8:26
in the dam
8:28
exactly yeah
8:30
the other complaint is the uh
8:31
fluctuation of hot water usually on the
8:33
upper floors and again just through
8:35
experience and having walked into the
8:37
mechanic room and literally feeling the
8:39
pipes under a demand condition i can
8:42
tell you whether that system's working
8:43
correctly or not and if it's not i know
8:46
what the problem is you know people look
8:47
at a swing check
8:48
and they go well it's a swing check you
8:50
know it's gravity closed
8:51
it should be working
8:53
keyword should be yeah uh in reality if
8:56
there's not an aqua stat or a timer or
8:58
something that stops that circulation
9:00
return pump that check the swing check
9:03
is literally lined in the open position
9:06
so it can't activate it can't close if
9:09
it sees the backflow condition
9:10
so i like to avoid the use of swing
9:13
checks whenever possible but prefer to
9:15
use spring checks whenever possible but
9:18
i've seen spring checks fail too
9:20
and the only way that you can diagnose
9:21
that is with your hand or with an
9:23
infrared camera or with a battle auger
9:26
and you're feeling the pipes if the
9:28
circulation return pipe's coming back
9:29
hot constantly you've got a good flow if
9:32
it's fluctuating you've got cold water
9:34
running backwards through that
9:36
circulation return and even when the
9:38
pump is on that pump's only capable of
9:40
generating so much pressure
9:42
and if the pressure differential is
9:43
greater than what it's capable it will
9:45
run water through that pump backwards
9:47
even though the pump is in the on
9:48
position so that's the other complaint
9:51
and then the
9:52
third complaint is not very common but
9:55
it's a royal pain to find is that
9:57
cross-connected valve
9:59
and it could be something as simple as
10:02
i've had people that were renting
10:04
uh hoover portable clothes washers that
10:07
they put into their apartment well if
10:09
they want to do a warm water fill they
10:11
have to open the hot and the cold water
10:14
that comes out of the spigot and give
10:15
you a little adapter like you use for
10:16
filling your water bed that basically
10:19
allows you to make one hose connection
10:21
to the washing machine itself so you
10:23
either get hot or cold or warm if you've
10:25
got bulbs open well if you've got both
10:28
valves open and the solenoid on the
10:30
machine closes you have a cross
10:32
connection
10:33
and that cross connection can come and
10:35
go so it's pretty tough to crack down
10:38
you have to ask that question of
10:39
management do you allow portable washing
10:41
machines in your apartments and if they
10:43
see yes and say i think that's probably
10:47
where the problem is and the only real
10:48
good solution would be to go and install
10:50
check valves on both the cold and sat
10:52
water supply
10:54
going through that kitchen sink faucet
10:55
itself
10:57
the cross-connected shower valve we've
10:59
already discussed that they're pretty
11:00
common right but there's also a
11:03
situation
11:04
where in a lot of these elderly senior
11:06
elderly housing projects that they will
11:08
do the road that you remotely want so
11:10
that they don't have to stand they can
11:11
sit in a
11:13
wheelchair and take a shower and a royal
11:15
shower okay so again if they close that
11:18
dumb valve that's on the remote shower
11:20
head but they don't close the hot cool
11:22
water supply going to that device and
11:25
there are not check valves
11:27
on either the hot or the cold water
11:28
supply going into that shower valve you
11:31
have a cross connection and again
11:33
it can come and go
11:35
so in those situations it becomes an
11:37
education process
11:39
you have to educate management to
11:42
educate the residents that they never
11:44
ever want to use that little remote
11:46
button on the one turn it off use the
11:49
share valve to turn it off
11:52
and then the problems go away
11:54
all right if they do that provided they
11:56
do that they do the other structure for
11:58
the time being
12:00
right right and you know residents
12:02
change we we use a lot of of
12:04
non-electrostatic radiators
12:07
there's education number one it's got
12:09
from zero to five on the number they
12:11
don't know what that means they're used
12:12
to looking at degrees fahrenheit right
12:14
so i tell them
12:16
three and a half is equivalent to 70
12:18
degrees fahrenheit set it and forget it
12:21
do not touch it right
12:23
and after we get done educating them
12:25
everybody works great and a new resident
12:27
comes in that doesn't understand what it
12:29
is or how it works
12:31
another first person to complain when it
12:33
gets a little cool outside hey there's
12:35
no heat coming out of my baseboard the
12:37
last place i lived in i could turn it up
12:39
in the fourth of july and it would
12:40
bother eat all over my body right
12:42
well you're in a different scenario here
12:44
our boiler changes the temperature based
12:46
on the temperature outside
12:48
and that thermostatic radiator valve
12:50
should be set for a maximum allowable
12:52
temperature
12:53
set it and forget it right turn it up
12:56
don't turn it down set it and forget it
12:58
yeah that's the beauty of that
13:00
management train that anytime they have
13:01
a new resident coming in that they hand
13:03
them
13:04
this letter of instructions that
13:05
explains to them how they're supposed to
13:07
operate their hitting system and then
13:08
again the complaints go away yeah that's
13:11
the beauty of outdoor resetting the
13:13
boiler
13:14
yeah
13:16
well you definitely have a lot of a lot
13:17
of good procedures in place on the front
13:20
side to evaluate these buildings and
13:23
and a lot of due diligence that you do
13:25
on the front end and i appreciate you
13:27
taking the time to share that with us
13:29
yeah
13:31
my pleasure i appreciate you guys giving
13:32
me the opportunity to do it i'm within a
13:35
year and a quarter of retirement and
13:37
when i retire i'll be
13:39
working diligently in my cnc shop i've
13:42
got cnc routers and cnc lasers okay and
13:46
so i'll be getting away from the
13:48
hydronics industry and getting into uh
13:50
making cool fun stuff yeah that's
13:52
awesome that sounds like a blast well we
13:54
certainly appreciate as many people as i
13:56
possibly can before i leave so yeah time
13:58
to get a chance to work with cliffy who
14:00
is fantastic for doing this
14:03
i'll be glad to do it yeah well we
14:04
appreciate that we appreciate your help
14:06
with coffee with caleffi and you taking
14:08
the time out of your day to join us here
14:11
all right
14:12
all right well gentlemen have a good day
14:14
and if there's any way that i can help
14:15
you or the industry feel free to give me
14:16
a call
14:18
we certainly will thank you mark
14:20
all right take care
14:21
thank you for tuning in if you ever need
14:24
help please feel free to contact our
14:26
tech support team anytime at
14:28
techsupport.usc
14:31
calefi.com
14:32
or call us during our business hours at
14:35
7 30 a.m to 4 30 p.m
14:38
central time
14:40
at
14:43
two 414-238-233 six zero
14:46
[Music]
15:03
you