Espar Hydronic Heaters
Espar Hydronic heaters are integrated into the cooling system of the engine and work independently of the engine, thus offers pre-heating of the engine and the vehicle’s passenger compartment. The thermal energy gained is then distributed through the vehicle’s own heat exchanger as forced hot air which heats the interior of the vehicle via existing air vents. The engine is warmed up with the residual heat in the cooling water.
Pre-Season Preventative Maintenance For Hydronic Heaters
Before the cold weather arrives, it’s recommended that your Espar HYDRONIC heaters receive a preseason check to ensure the heater is clean, free running and ready for a trouble-free season. Please use the recommended tools and follow the procedures as outlined in the heater manual while removing and reinstalling the different heater components.
The heaters should be inspected and repaired by an Espar trained Technician, as follows:
1. Check all electrical connections from the heater to the batteries. Check for wear and abrasion along the length of the harnesses. Repair or replace the harness whenever the harness insulation is broken or damaged. Check the battery connections. Clean any corrosion at the terminals. Replace the battery terminals if the corrosion is severe. Check the fuse for corrosion and the correct rating.
2. Check all clamps and hoses. Replace as required.
3. Check the condition of the exhaust system. Check for holes and breaks in the exhaust piping. Replace the exhaust as necessary.
4. Check the fuel pump filter ‐ clean or replace it as necessary. For heaters with external fuel pumps, ensure that the mounting angle of the fuel pump is in between 15‐35o. An incorrectly mounted fuel pump may lead to excessive carbon issues. Check the fuel lines for possible leaks, loose clamps, etc. Once the entire fuel system has been checked and issues, if any, are corrected, it is advisable to do a fuel quantity check.
5. Check and clear clogged weep holes on the side of the heater body. Look for any indication of coolant leakages. If leakage is suspected then remove the cover with water pump assembly and inspect and replace “O” rings on the water pump housing. Closely inspect the heater waterjacket for leakages and replace the “O” ring between waterjacket and heat exchanger. If the waterjacket is cracked, replace it.
6. Remove and replace the glow pin screen. Make sure that the new screen is installed correctly as outlined in the repair manual for the heater.
7. Remove and check the glow pin. If it shows signs of dissimilar colour or if the glow pin is in any way distorted, replace it.
8. The coolant pump should be removed and the impeller checked for damage. Any dirt or metal particles on the impeller magnet should be removed and the cavity in the pump should also be cleaned. Please Note: coolant pumps are not covered by warranty if the vehicle’s coolant system is excessively contaminated. Refer to Technical Circular 250.
9. Remove the flame tube and check the condition of the flame tube end. The flame tube should be light brown in colour with no excessive carbon at the end of the flame tube. Check for carbon build up on the burner “nose” at the cold end of the flame tube. Any carbon covering the air slots should be removed. Check the inside of the heat exchanger and scrape any loose carbon out from between the fins in the heat exchanger. Re‐install the flame tube replacing all gaskets.
10. Re‐assemble the heater and test operation. The heater should be bench tested for 15‐20 minutes before returning it to the vehicle.
11. Regardless of the season, run the heater every month for a minimum period of 15 minutes. This will help the heater burn away any combustion residue in the burner chamber and prevent corrosion in the waterjacket and decay of “O” rings
Arctic Traveler Canada is an MSD (Master Distributor) for Eberspaecher products and a technical leader actively involved in projects driving the mobility of tomorrow. Call 1-800-295-4156 for more information about mobile heating solutions.
When it comes to air conditioning, a good preventative maintenance program will increase operating time and save money by identifying concerns before they become problems. Once the hot weather arrives, implementing planned maintenance allows you to schedule repairs instead of reacting to sudden unexpected issues. A/C filters, coils, and fins require regular maintenance to ensure optimum performance and neglecting necessary maintenance results in a steady decline in performance and increased energy use.
Clogged, dirty filters restrict airflow and reduce a system’s efficiency. When airflow is restricted, the air that bypasses the filter will carry dirt directly into the evaporator coil and reduce the coil’s heat-absorbing abilities. To ensure efficiency, routinely clean or replace filters.
The condenser and evaporator coils collect dirt over time but a clean filter helps to keep the evaporator performing well. Debris reduces air flow, insulates the coil and reduces its ability to absorb heat. Being exposed to the elements, it is easy to see the dirt collecting on the fins. Cleaning the coil fins and removing any debris around the coil will ensure optimal performance.
The aluminum fins on evaporator and condenser coils are easily bent and can block airflow through the coil. Air conditioning wholesalers sell a tool called a “fin comb” that will comb these fins back into their original condition.Remember to always use caution when performing preventative system maintenance, as ambient conditions (heat load) will increase refrigerant hose temperatures and don’t forget, having the right quality parts on hand makes all the difference.
See How To and Which Components to Inspect and watch this video to learn more about Basic A/C Troubleshooting.
Heavy-duty A/C system components rarely fail. In fact, the system fails the components because of contaminated refrigerant oil and general lack of preventive maintenance.
Tech Tips From RedDot
One of the best ways to improve uptime and reduce maintenance costs for the customer is to promote a basic visual check of major A/C components, hose connections, and fittings at regular intervals, like with every engine-oil change. This inspection routine has another benefit: it can generate business for your parts and service department.
Many A/C components are consumable items. It’s more cost-effective to replace them than to repair them. So preventive maintenance is an opportunity to sell a range of OEM-quality all-makes replacement parts for the air conditioner. Here are some examples:
1. RECEIVER DRIERS
The receiver-drier’s moisture indicator provides a quick visual cue about the refrigerant’s condition: a blue dot means the refrigerant is dry; pink, white, or grey indicates acid or moisture in the system. Checking the sight glass during an oil change or any scheduled maintenance procedure means the truck can receive necessary service while it’s there in the shop, before moisture and acid damage critical A/C components and lead to a failure on the road.
Dust, bugs, feathers, and other debris collect on the face of fins and tubes and act as a thermal barrier, making it hard for the condenser to shed heat. Condensers also fail because of vibration, which can cause hose connections to come loose and fatigue the condenser tubing adjacent to the fittings. Every 12 months, the condenser should be cleaned (taking special care not to bend or damage the fins) and the hose connections securely clamped.
3. COMPRESSOR/CLUTCH ASSEMBLY
The compressor provides the mechanical energy to circulate refrigerant and manipulate the pressure inside the system. It’s the heart of the A/C system, and the No. 1 HVAC maintenance expense item. Excessive noise and poor cooling performance are the two most obvious symptoms that a compressor is failing. Replacing the compressor involves pulling down the system, which adds refrigerant recovery and recharge to the repair cost.
Next time you see, “A/C won’t blow cold air” on a work order, note that the repair and downtime probably could have been avoided with a simple visual inspection of the truck’s air conditioning system. Any time you change the truck’s oil, check the A/C.
Take these steps to inspect an A/C compressor to ensure it really needs replacing before you pull it from a heavy-duty vehicle:
1. Is The Compressor Rotation Smooth?
With the vehicle off, turn the compressor shaft with a 14-mm socket. If you feel grinding or hanging as you rotate the shaft, it’s probably due to broken components within the compressor. If the rotation is smooth, move on to Step 2.
2. Is The Coil Getting More Than 11.5 Volts?
Take a reading with the engine running and the clutch engaged. If there’s insufficient voltage, get to work on that. Otherwise, move on to Step 3.
3. Is The Coil Resistance Between 2.8 And 4.4 Ohms?
Any resistance outside this range will prevent the clutch from engaging or will cause used circuits to open. If the answer is yes, continue to Step 4.
4. Is The Compressor Able To Produce 350 Psig Or More?
If not, leave the compressor where it is. The system may have a low refrigerant charge because of a leak that needs repair, or a high-side blockage that limits refrigerant flow to the compressor.
Tech Tips from Red Dot
” We see lots of compressors that are returned fully functional and therefore not warrantable.
Get the diagnosis right. Inspect an A/C compressor before you pull the component from the vehicle.”
For expert insight into common failures and causes, watch Examining Compressor Failures on ATCTV
While there, check out How To and Which Components to Inspect and Basic A/C Troubleshooting to further your understanding of A/C Systems.
For more information about AC Compressors or any HVAC component, call the mobile HVAC specialist Arctic Traveler Canada at 800-295-4156.