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HomeMy WebLinkAboutLevelock Phone Logs MTG Notes Points of Contact 1990TRIP REPORT TO: David Denig-Chakroff Director, Rural Programs FROM: John R. Bulkow Rural Systems Engineer SUBJECT: Trip Report Manokotak, Clark’s Point, & Levelock DATE: February 20, 1990 PURPOSE The Alaska Energy Authority has agreements with the Southwest Region School District and the Lake & Peninsula School District to assist in the design and construction of waste heat systems in Manokotak & Clark’s Point and the redesign of the waste heat system in Levelock. This trip was made to obtain the required design information at all three sites. MANOKOTAK I left Anchorage on the morning of February 5 and travelled through Dillingham to Manokotak via Markair & Markair Express. On arrival in Manokotak I went directly to the school where I met with the principal, Kevin Hoyer. Mr. Hoyer indicated that the heating system of the school had recently been rebuilt and was working well. I then spent a few hours photographing and making as-built sketches of the school boiler room and fan room. There is ample room for waste heat recovery equipment in the boiler room. The return header of the school heating system already has valved and capped tees in place for future connection of a waste heat system. Next the power plant operator was contacted. He provided access to the powerhouse but did not have time to discuss connecting a waste heat recovery system. The powerhouse is an approximately 16’x50’ uninsulated wood frame structure with metal siding and a concrete floor. The building contains three 300 KW generators. At the time of my visit only one of the units was operating and one of the units was partially dismantled (presumably for repairs). Each generator set currently has a skid mounted radiator. Connecting a waste heat recovery system would require removing the skid mounted radiators and providing remote radiators, a heat exchanger, & header piping connecting the existing generator units to the new equipment. There is sufficient space inside the powerhouse for a waste heat recovery heat exchanger and space behind the powerhouse for remote radiators. After completing my inspection of the power plant I investigated the area between the school and the powerhouse for possible routes for the waste heat arctic piping. There are two logical routes for the piping to take. One route could follow the existing roadway easements. A more direct route would require obtaining a right-of-way across what appears to be private property. At 4:45 p.m. I took a Markair Express flight back to Dillingham where I spent the night at the Bristol Inn. The next morning I met with Don Ford, the maintenance supervisor for the Southwest Region School District. Mr. Ford took me to the school district maintenance building where I reviewed the Fryer/Pressley design for the Manokotak school heating renovation. Together with one of the school district welders we discussed Southwest Region School District criteria for waste heat recovery systems. In general they like our standard waste heat designs, however, rather than tying the arctic pipe directly to the school heating system as we sometimes do they would prefer to isolate the school heating system from the arctic piping with a heat exchanger. At this meeting they also indicated that they were down to about 400 ft of arctic pipe and completely out of arctic pipe fittings, foam packs, foam pads, etc. CLARK’S POINT At 11:00 a.m. Don Ford & I took a Peninsula Air flight to Clark’s Point. We first checked in with Richard (Dick) Montgomery, the school principal, and then went to the power plant. Sam Clark, the power plant operator, met us there. Don Ford spoke with Sam Clark in the plant office while I photographed and made as-built sketches of the generator cooling system. The plant has three generator sets: a 50 KW, a 60 KW, & a 100 KW. Sam Clark indicated that power is provided almost exclusively by the 60 KW unit. The generator engines at this site have already been connected to a common header and a remote radiator. Three unit heaters for heating the powerhouse are connected directly to the header and a shell & tube type heat exchanger was incorporated into the system for future connection of a waste heat recovery system. The system appears to function adequately despite the fact that in some places the cooling piping reduces in size for no apparent reason. Connecting a waste heat recovery system for the school would require a plate & frame type heat exchanger and replacing the undersized piping in the cooling system. After breaking for lunch we next inspected the school boiler room, fan room, and crawl space. The boiler room is congested and has little space available for a waste heat recovery heat exchanger. Capped tees terminating in the crawl space are already installed in the heating system return header for connection of a waste heat recovery system. Unfortunately, one of these tees is incorrectly placed to be utilized. The most viable location for a waste heat recovery heat exchanger is in the fan room located directly above the boiler room. At 4:00 p.m. Don Ford and I returned to Dillingham. LEVELOCK On the morning of February 7 I proceeded to Levelock via Peninsula Air. Chuck Beatie, maintenance supervisor for the Lake & Peninsula School District, met me at the airport and took me to the school. As noted by Peter Hansen on a previous visit to this site, the school boiler room piping is quite complicated. There are certainly more pumps than necessary for this type of system and some of these pumps may be oversized. Chuck Beatie indicated that he would like the system redesign to simplify the piping as much as possible. Chuck Beatie also indicated that he liked the Grundfos series 200 type pump but would rather not use the dual head version of this model. It should be noted that there are two domestic water lines in the boiler room that are insulated with asbestos insulation. The School District is aware of the asbestos problem and has the area posted. Care should be taken, however, to avoid disturbing this piping while working on the heating system piping. The power plant has three generator sets: two 130 KW units and a 50 KW unit. The 50 KW unit and one of the 130 KW units are connected to a common header. The piping of this common header runs through a shell and tube type heat exchanger, an AMOT valve, and then either back to the engines or through a remote radiator and back to the engines (depending on the operating position of the AMOT). Cooling piping for the third generator set is identical to the common header except there are no connections to the 50 KW unit. The two shell and tube heat exchangers capture the waste heat for the school. There are 2-way control valves in the secondary side piping coming from the heat exchangers. It appears that these 2-way valves shut when a temperature switch in the primary piping senses that the supply temperature from the engines has dropped below 145 degrees Fahrenheit. This protects the engines from being overcooled but leaves the waste heat pump trying to pump fluid through a blocked line when the valves close. No controls for the remote radiators were evident, apparently the remote radiator fan of whichever radiator is connected to the running generator set is allowed to run continuously. Work that should be done in the power plant includes replacing the two shell & tube type heat exchangers with a Single plate & frame heat exchanger, replacing the 2-way control valves with a 3-way control valve, and providing two speed controllers for the remote radiators. At 5:45 p.m. I returned via Peninsula Air to Dillingham where I took a Markair flight back to Anchorage. € php? 1% oO L | a3 K rag * 2-Uat WALES gS o » 2 F-O' Crest iF atr. e ww, your’ Surry Teme 2 Zz pest FAUS Second ys PIAOABNFA} Bey BSN AW CL sa7 ae SE : eh Nis | Lévetoce HY NGI tig ce ca ¢ Eee coud 5 int LD cuT rae as Bue _ ce Back $55 Errored 388 out Coup ST ate oat Fro Ux Beue Peocw we HOLD - gaEe2es SC-IOM-7 FS TeaettHe surest catyveiR iPstraestioe gd OrthaTI on Aru Ad Sar | 13:38; sg8 SUES EsguE > at 42-389 200 SHEETS 5 SQUARE A” 4 am’ ys, ae 7 i? ( x © Soro x< co airy? fas a PO YI “ owe, P yore) cw 3! 2072274237 “VOOR AS ap. sat f ale ‘er 1 oi XX VY 5 > Rear YAS Ge¥ %/60 Q shy ~N SS x = re ny iy at Levelok Schoo L 0 Bor her Reorr /1-1¥-€¢ a Yoo & jfoo t Tot Mo teoo > Sls Uoy w PL ducts SHA. | Boi ler Koon. 1-19-88 PRET oe ee Ars FSI ytoo cm |.§ °P Gan Moho oes py 0.41 0WF FE aysiu? ES Jah en~ stbeA! Fan F- C pre pyo him 2./6 N4P Ge. Lie OGRE A: Yee 4 TO: Don Shira, Director Program Development & Facilities Operations FROM: Pat Woodell \ Development Specialist Peter Hansen toy Rural Systems Engineer / SUBJECT: Trip Report Levelok & New Stuyahok DATE : November 23, 1988 LEVELOK On November 15-18 we traveled to Levelok and New Stuyahok to evaluate potential projects for the Rural Systems Efficiency Program. The trip, originally planned for two days, was extended to four days because ice fog grounded all air transportation in the Dillingham area. On November 15 we met with City Administrator Dave McClure and Levelok’s Village Council President, to discuss the Efficiency Program and solicit information on the community's energy needs. After a brief meeting, we looked at the the furnace, thermal and lighting systems in Levelok’s future recreation hall. This building has strong potential for complete retrofit work on all systems. In summary, floors have no insulation, ceiling insulation in one section is scarce and in another section is possibly water damaged. Two mobile home-style furnaces appear to be ill-suited for the building’s current use (noisy blower fan in conference room, poor stack exhaust). Many fluorescent tubes and ballasts are in disrepair. Complete notes and recommendations are presented in the attached energy audit. The Village Council has $6,000 in Suicide Prevention Funds that can leverage Power Authori- ty funds for the project. After completing a review of the recreation hall, we met with school principal Joe Scheiber to discuss the school’s high electri- cal consumption. Last year’s PCE records showed a consumption of 90,320 kilowatt hours. A review of the boiler room and its waste heat system hookup identified the high usage problem. The system uses 2 each 417 MBTU output boilers rated at 4.25 gallons per hour. Water temperature registered at 118 F rather than the usual 180-190 F. Pumps and heat exchanger were inappropriately-sized, causing excessive electrical load. Specific details on problems with this system and photos will be documented in a separate report for the school district in Dillingham. Following our meeting at the school, we contacted the head of Levelok Electric Cooperative and requested permission to inspect the generator house. Information and photos on the plant will be forthcoming in a separate report. NEW STUYAHOK The trip to New Stuyahok was timed to assist with the installation of the waste heat system on AVEC’s generator house. Key materials were on-site when we arrived, and missing materials were ordered. Work was proceeding satisfactorily at the time of our departure. Dillingham school district administrator, Martin Myhre, had re- quested that we look at the grade school in New Stuyahok in conjuction with our visit. According the Myhre, the old BIA build- ing had some thermal problems. While Peter worked on the waste heat system, Pat previewed the grade school building and interviewed principal Nels Nichols about his concerns. We agreed that the building was structurally sound and not a great deal could be done to it insulation systems without a great deal of expenditure. The building's lighting system was good, and a few minor recommen- dations will be made for upgrading lighting levels. These comments will be included in our combined Levelok/New Stuyahok report to the school district. A separate lighting system audit has also been prepared on the New Stuyahok grade school. Principal Nels Nichols also requested that Pat look at two separate duplex buildings (teachers’ quarters), that are having condensation problems in the attic. An inspection of the two structures re- vealed multiple problems with ventilation systems, the manner in which insulation was installed and lack of vapor barriers. Recom- mendations for improvements to these buildings will be made in a report to the school district. No recommendations are made for work in New Stuyahok under the Rural Systems Efficiency Program. FIELD TRIP REPORT Date: 11/14/88 Site: Levelock Crew: Pat Woodell, Development Specialist Peter N. Hansen, Rural Systems Engineer Subject of report: High power consumption in Levelock school. We looked at all power consuming devices in the school, and it appeared that lighting loads were normal for a school of this type. No electric heating or water heating devices were found, and it appeared that fan loads were reasonable. Air handling fans were controlled by time clocks and while the fans certainly account for a significant part of the electric loads, we did not see any major problems. It appeared that pumping requirements in the boiler room were quite excessive, and the reason for this was traced back to the waste heat recovery system, which supplies heat from the local power plant to the school. Approximately 4 kw of pumping is operating continously in the boiler room, and the annual consumption for this could be as high as 25,000 kwh. While the boiler room piping is a sad example of engineering performed with no concern for operating costs, the real problem can be found in the design of the waste heat recapture system in the power plant. On the day of our visit the ambient temperature was approximately 0 degrees and the load on the power plant was approximately 55 kw. In spite of the waste heat recapture system only being capable of providing a supply temperature of 118 degrees to the school, the generators needed additional cooling as the AMOT thermostatic three way valve was providing flow to the remote radiators. The radiator fan (2 hp) was operating continously. The waste heat system piping in the power plant is unnecessarily complicated and the heat exchangers are of the wrong type. (Tube and shell type). It is recommended that the heat exchangers be replaced with an appropriate heat exchanger and that the piping be simplified. These changes would raise the temperature available to the school, thereby cutting the flow requirements in the waste heat system to a fraction of the current requirements. With higher supply temperatures available to the school, flow requirements could be significantly reduced throughout the school's heating system. The remote radiators in the power plant should be equipped with 2 speed motors and thermostatic controls. This would reduce the station service loads significantly. It is interesting to note that while the power plant's electric systems appear to be well designed and constructed, the mechanical systems are a mess. It is recommended fhat the piping layout in the school boiler room be changed to a more traditional and much more energy efficient system. The existing system uses separate pumps for circulation through each boiler; this is a waste of energy as the head losses through the boilers are so low, that any pump used for this purpose will operate at a very low efficiency. Circulation should be provided with the main circuit pumps. With these changes, it should be possible to cut pumping costs by almost 75%. New Stuyahok Schools Review of Thermal and Lighting Systems (November 15-16, 1988) New Stuyahok Grade School Upon arriving in New Stuyahok I contacted principal Nels Nichols to discuss building age, insulation levels and any special problems experienced with operating the building. A preview of the building suggested that it was in excellent repair, with no major structural problems. It appears that this old BIA building was re-sided in 1981-82, but no insulating board was placed under the siding when it was in- stalled. The flat roof is enclosed and insulated, with some problem of water leakage in the east-west hallway on the south end of the building, where a new addition with a slightly-higher wall structure was appended. The flashing at this join may need to be evaluated. Floor insulation level are unknown as joists are enclosed with one to one-and-one half inch celotex board. Any insulation retrofits to this structure would be quite expensive because of the closed envelope systems, and nothing is recommended at this time. Windows in the grade school are combination fixed-pane with inside opening awning units. All but a few are fitted with metal clip-on storm windows. Two fixed-pane windows in the kitchen and two in the southeast classroom are single pane windows, and it is recom- mended that they be fitted with storms. Apparently there are some problems with the storm clips loosening in wind or when windows are slammed. There are a few minor infiltration problems, which can easily be corrected. Inner hallway double doors leading to exits have one-half inch gaps that could be closed by nylon brush weatherstrip (obtainable at overhead garage door companies). The fire exit door in the northeast classroom has a large threshold gap, which allows cold air infiltration from the adjacent outside doors. Again, this can be easily resolved with nylon brush weatherstrip. A review of classroom and hallway lighting revealed adequate levels in all but one classroom. This room, located on the west side of the building next to the handicapped restroom, has lighting in the 8-12 footcandle range in most parts of the room. By contrast, other classrooms average about 30-40 footcandles. The west wall activity area in the affected classroom appears to be underlit for most tasks. Hallway lighting is excellent throughout. The center of the north-south hallway could benefit by the addition of another fixture in an area that is a little dim. Lighting in the grade school kitchen is all incandescent; six suspended fixtures about 150 watts each. The pantry and range hood also have lower-wattage incandescent bulbs. This room could eventually benefit by changing out incandescent lighting to suspended fluorescent fixtures and slightly upgrading lighting levels in the center work area. The food service areas appear to have sufficient illumination. A discussion with the custodian revealed that 40 watt tube fluores- cent fixtures have recently been delamped to 32 watts. Principal Nels Nichols added that all new ballasts had been installed along with rewiring of circuits. Lighting circuits are well-divided to avoid putting large rooms or long hallways all on one circuit. The cafeteria/multi-purpose area, a 47’ x 34 ' room, has three separate circuits. The north-south hallway is on two separate circuits; classrooms and restrooms all have multiple switches. If security is not a consideration, timers could be installed on hallway lights, allowing them to switch off at night. Duplex Buildings According to Mr. Nichols and building residents, two duplex teach- ers’ quarters near the high school have experienced continuing, ceiling condensation problems. Although the two buildings are different in age and roof structure, lack of a vapor barrier ad inadequate roof ventilation appear to be the main contributors to ceiling water leakage. Older Duplex This building has a pitched roof with small gable end vents blocked by wind baffles on the exterior. Space between the baffle and the vent is approximately two inches. Eaves are vented by a series of circular 1.5 inch holes, open and visible from inside the attic. Net free vent space requirements do not appear to be high enough for the ceiling area of the building, particularly since a vapor barrier does not appear to be in place. Resident Chris Bergman noted a continual leaking problem in the hall closet. Visual inspection showed frost buildup over a two-inch area on the closet ceiling. This is apparently caused by loose-fitting insulation over the ceiling area, which formerly provided vent pipe access for the old heating system. Visual inspection of the roof deck showed some frost buildup on the roof deck and nail heads. While some frost buildup is to be expected, this situation appeared to be a little worse than normal. The arctic entry way to the duplex units have flat roofs with incandescent light fixtures built into a ceiling. Entry way ceilings are buckled and water damaged, showing approximately two inches of fiberglas insulation with a large airspace above. The airspace is not common to the attic, and the entryway ceiling appears to be acting as an unvented flat roof. Newer Duplex This building has a modified hip roof with peak gable venting and no soffit vents. Icing on the inside roof deck appears to be severe, particularly where roof trusses meet the top plate of the walls. The roof deck is black at this interface, suggesting a long-standing problem with moisture build up. The dryer vent through the attic is fully insulated and does not appear to be a contributing factor to the condensation problem. Water drips through light fixtures during spring warm up--the classic sign of a condensation problems. It also appears there has been water runoff to other parts of the ceiling in the past, as the insulation board in one of the units is buckled. One of the tenants noted that the school custodian sometimes places sheets of visqueen over fluorescent light fixtures in the attic during breakup. This practice only serves to re-route frost melting from the roof deck, allowing fiberglas to absorb the moisture and reduce its insulating value. Recommendations Insulation in both attics is thin in many areas and loosely in- stalled. Gaps between sections of insulation are creating cold spots on the ceiling, which results in problems such as the frost buildup in the hall closet. Moisture tunnels resulting from gaps between sections of insulation increase problems with frost buildup on the roof deck. The most economic solution to the condensation problem would be to remove existing insulation and install a new vapor barrier between ceiling joists. The barrier should extend up the sides of the ceiling joists, but leave the tops open to prevent water damage to wood. The custodian thought a vapor barrier might already be present, but it was not observed in the few areas that were hand-inspected. At this juncture, soffit venting for the newer duplex should be considered prior to reinstallation of fiberglas. This would improve the circulation flow of air in the attic, allowing moisture to be carried away before it has a chance to freeze on the roof deck. Insulation in both units should be re-installed with sec- tions carefully joined to prevent cold spots in the ceiling and moisture tunnels in the attic. Cardboard baffles should be-installed along the soffits to allow for free passage of air into the attic. These may be stapled to the rafters to prevent popping and blocking of the soffit vents. The arctic entry ways in the older duplex are not heated areas, and do not need to be insulated. An economic way of preventing further structural damage might be to rewire ceiling lighting fixtures to an inside arctic entry wall, remove water-damaged fiberglas and ceiling board, and nail in a new plywood ceiling. Holes could be drilled through the front and back sides of the entry way roof joists to allow any moisture to escape from this trapped area. Zone valves on the heating system in the older duplex might need checking. One of the residents noted that a thermostat turned up to 75 F still could not produce enought heat to keep the unit warm. New Stuyahok Grade School Electric Inventory Appliances and Motors The following is a list of appliances noted during a review of the grade school. List does not include furnace pumps and motors. Appliance/Motor Rating (KW)* Voltage 14 cu ft. refrigerator Un 115 Silver King Beverage Cooler 2.4 115 Propane warming oven 5.0 115 Traulson commmercial refer 7.1 115 Victory Raetone commercial 8.3 115 refrigerator McNurn vent fan (heat exchanger) Un 115 Modle unit heater Un Un Triumph mixer Un Un Lighting System Area Kitchen Range Fan Pantry Lunchroom North Hall N.E. Class Photocopy E. Class N/S Hall South Hall Library S.E. Class W. Class W. Class Annex Supply Closet Boiler Room Notes F: Fluoresce I: Incandesc Type No. Lamps/Fixture Watts Total Wattage I 6 1 150 900 I 2 1 75 75 I 2 2 75 150 F 24 2 32 1,536 F 3 2 32 192 F 6 2 32 384 F 2 2 32 128 F 14 2 32 896 F 5 2 32 320 F 3 2 32 192 F 18 4 32 2,304 F 18 4 32 2,304 F 8 2 32 512 F 4 2 32 256 I 1 1 100 100 I 2 1 75 150 nt ent Grade school, high school and duplexes all on one electric meter Boilers and Hot Water System Grade school is heated by two National U.S. 37 Series all fuel boilers. Name plate rating is 484 MBTU output, and 6.20 gallons per hour. Boilers appear to have been derated to 3.1 gallons per hour. Hot water tank is a Bock Model 72 E with a firing rate of 1.50 gallons per hour. Its recovery rate is listed as 180 GPH. Tank size is 68 gallons. | ta” | WE, Cass 94" Kae i ----| Kit Chen ‘ ot’ Wer ther _ IL; $= — f—— hfe Listy 4) OTA OA “~ —~) sev ott ~~ Ss Uggrede | \rent™ fevels | Anher J | ; _ Coset | APSA rms Be ler Mem < : Seep 'y ay ACS peeme a7 Pantry | tI Cafeterra Ju Apurpese 3y’ < gy > _/) N ere fo scales not achiral Compe ss < eH \ pow ¥ t XY 4 NM —> wv