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real issue for the thousands of stranded Acadia owners is
the fact that most HVAC companies have turned their backs on
their Acadia customers. Mr. Friedman’s inspiration- Gabe
Josephs (Josephs LLC , South Deerfi eld MA) - not only stuck
by his 30 initial customers - but also supplied daily
service information at no charge to any and all who
contacted him through the Google Acadia Site (http://
groups.google.com/group/ hallowell-acadia?lnk=srg). “It is
important for HVAC contractors to know that these units are
worth servicing - that help is available for technical
questions via www.savemyacadia.org and its principals - and
that if the FWO is not installed there is a high probability
that the compressor will fail --- a sad thing for any family
that made a recent investment in green technology” noted
Mr. David Friedman.
He added “The number of
people who have logged onto our savemyacadia.org is up to
about 150 and new high quality discussions continue to make
it an invaluable place for either HVAC suppliers or owners
to look to for advice”. There are reportedly 3,000 Acadia’s
in the field.
The goal of
SaveMyAcadia.org is to widely distribute technical and
service information to HVAC techs – allowing the Acadia
units to be routinely serviced. To that end the site will
have technical documentation, FWO’s, service guides and
general discussions about various performance issues.
Product users generally report that given quality
installation including proper sizing and ducting, they got
good energy efficiency when units were new. The major
failures were associated with a fl awed starting circuit
that has been redesigned and extensively tested for
reliability.
This fl awed circuit was
not present in the ACHP - an earlier version of the Acadia.
In addition, there have been widespread reports of improper
de-icing and various erratic heat mode problems. Mr.
Friedman noted “We believe that the core cause of these
issues was a combination of inferior temperature sensors,
some poor installation procedures for these sensors, and
perhaps a connector problem inhibiting their proper
connection to the PCB board which runs the Acadia”. Since
the starting circuit fix was released - some 25 people have
installed the FWO with no additional reported failures.
Reason for FWO:
(Applicability: The work order is applicable to all
Hallowell Acadia 2, 3 and 4 ton units.) The current dual
relay/dual contractor motor starting circuit has two
significant design faults. The electrical circuit uses two
contacts of a single contactor to both (with the first
contact) power the given direction of compressor operation,
and with the second to control a low level current coil of
the potential relay needed to control start cap disconnect
for that direction of spin.
Due to either arcing, or
due to environmental contamination if an open relay, or most
probably due to the uneven wear on the power verses the
logic contact – the logic contact has repeatedly failed
open. This failure propagates by preventing the potential
relay from operating, holding the start cap in the circuit,
often blowing the start cap and then damaging the
compressor.
A second and perhaps more
significant problem is that this circuit –although
specified and authorized by Bristol, produces very high
torque starting and we have been advised by Bristol that
they “prefer” that we use equalized start and PCTR start
method which limits starting surge to on the order of 10
amps. In the Acadia design, there is a 2-5 minute dwell time
between starts which allows for the differential pressure to
bleed to about 1/3 of max, and thus there is no need for the
maximum starting torque.
Source: Save my Acadia Org.
- Gabe Josephs and David Friedman David Friedman continues
to consider further improvements. He is testing ways to add
breaker protection to individually protect each of the three
possible compressor modes.
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