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Northeast HVAC
News
Cure Available for Ailing
Acadia Heat Pump.
Problem can be reversed by installing a $30 part
Hallowell International LLC, which
manufactured residential and commercial heat pumps, got its
start five years ago with financing help from the city of Bangor
ME. Its pumps, including the Acadia heating and cooling system
that was marketed specifically to colder climates, are among the
latest heating alternatives for a nation heavily dependent on
fossil fuels.
Although Hallowell grew fast in 2008, aided by increased fuel
costs, the company struggled over the last couple of years.
Those struggles have been compounded by customer frustration,
including from one of the company’s biggest customers, a
military housing project in New Jersey that purchased
1,370Hallowell units — 30 percent of which have failed — over
the past three years.
Hallowell International is now defunct and David Friedman, a
retired engineer from New Hampshire, said a majority of failures
of heat pumps made by the Company can essentially be reversed by
installing a $30 part.
Story
continues below ↓
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The 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 (https:// 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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