Category Archives: Heating efficiency

Boiler Problems in Conjunction with Pump Sizing and Placement

People will often have a their cast iron boilers replaced with 90% efficiency boilers to save money . When these boilers are being installed you MUST follow the manufactures recommendations for piping methods and pump placement. These are extremely important to follow strenuously or else many other problems could arise. A lot of these problems may not be noticed or show up for up to 3 years. Which often times will be as the warranty expires. The problem with these issues is when they occur they often are confused with normal problems. Such as; Temperature and pressure relief valves (TNP’s) , Expansion Tanks, Fill Valves, Zone Valves and Air Separators.

When these problems are fixed they will keep rearing their head and will start to cost a lot of money. It may seem as if this issue will never go away. This is when you need to have a skilled boiler technician come in and take an extensive look at your system. The technician needs to be looking at all variables of your system. Starting from the very beginning.

First the technician will need to make sure that your boiler is properly sized for your home. This is extremely important because if your boiler is undersized it will not properly supply your home on a day when every zone is calling (all rooms need heat). And if your boiler is over sized you will be dealing with boiler short cycling (turning off without reaching peak efficiency)  when there aren’t enough zones calling. When your boiler is over sized you also risk over heating rooms, because your boiler is then heating up the water too quickly and not able to properly monitor the temperature of water it is sending to your zones.

The next variable to look at is your how the boiler is piped and if it is to manufacturers recommendations. This is one of the problems that goes unnoticed by many installers and technicians. This is important because if its not piped correctly your hot water may be mixing before serving the zones which will cut your efficiency down and in some cases in half. Sometimes this can be pricey to fix, but this is extremely important and worth the investment. Because if your boiler is running at max efficiency you will save more money each year on your utilities. Therefore you will get a return on your investment to re pipe your system.

The other very important part of your system are your pumps. If your pumps are in the improper location they will not properly serve your zones. Often times if your pump is placed incorrectly. The water will take the path of least resistance and can mix with cold water therefore crushing your efficiency or the water may push back to your boiler and overheat your heat exchanger causing it error out on high limit. When your boiler codes out on high limit this will make it so your heating or domestic needs are not met. This can go unnoticed in heating and DHW (Domestic Hot Water) often because if you have a really big zone calling. The Boiler still be distributing enough water so that your boiler will not error on high limit. When you have a call for a smaller zone it will then create that issue. When your boiler is supplying a DHW tank this can go unnoticed because you will still have the hot water you need and your tank will still be satisfied but not in the most efficient way possible.

The problems previously mentioned will sometimes take months or even years for the problem to go noticed. Making them very confusing and frustrating for the customer and also the technician. This is something that can be very hard to explain to a customer and often times ends up being blamed on a technician. Even when the original installer can be to blame. Hydronic systems can be very tricky to dial in once installed improperly.

 

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Troubleshooting Power Vent Water Heaters

Venting

When troubleshooting a Power Vent water heater the venting often goes unnoticed even if there is an issue. The venting is so important to inspect on Power Vent Water Heaters because if they are sloped the wrong direction condensation will makes its way to the blower and damage it. Power vents don’t always form condensation, but there are a couple different variables that do cause them to condensate.

-Ambient temperature and humidity of installation location

-Ambient temperature and humidity of venting space

-Vent distance, slope, and correct product usage

-Vent has slope minimum of 1/8″ AWAY from the blower – Horizontal Applications

-Know the proper vent lengths for the model water heater (see table below)

These are the variables you need to pay especially close attention to when inspecting the venting. If you do notice an issue where the Power Vent is condensating a condensate kit is available to install. This is a Fernco exhaust adapter with a drain outlet that you pipe to the drain using vinyl tubing. An inexpensive part that will solve the condensate problem.

Check for vent blockage and determine if the vent could become clogged by surrounding vegetation. If so, consult with the home owner on a solution to make sure the problem does not repeat itself.

Its extremely important to make sure there is adequate air for combustion and ventilation. An insufficient supply of air will cause re-circulation of combustion products resulting in air contamination that may be hazardous to life. In Such conditions you will notice a yellow,luminous burner flame, causing carbon build up or sooting of the combustion chamber, burners and flue tubes with possible damage to the water heater.

Vents are susceptible to freezing and can be very easy to overlook. If the burner wont stay lit you should check to make sure there are no obstructions and investigate the possibility of frozen vent.

Troubleshooting codes and Vent Length Table

The link below includes a table to troubleshoot any issues you may have

The link also includes Maximum vent length including number of allowed elbows

vent-length-table-troubleshooting-codes-and-cause

Proper Combustion Air

Combustion air is very important for a water heater to run correctly. All different variables should be considered. When an exhaust fan is installed in the same room with a water heater, sufficient openings for air must be provided in the walls. Undersized openings will cause air to be drawn into the room through the venting and causing circulation of combustion products. A very common solution to this problem is the installation of a louvered door.

The formula to correctly determine proper openings

All air coming from inside the building: an opening must have a minimum free area of 1 inch² (6.5 cm²) per 1000 BTU (0.29 kw) per hour of the total input rating of all gas utilization equipment in the confined space, but not less than 100 inches² (645 cm²). One opening must be within 12 inches (31 cm) of the top and one with 12 inches (31 cm) of the bottom of the enclosure.

All Air coming from Outdoors: The confined space must be provided with two permanent openings, one commencing within 12 inches (31 cm) of the top and one commencing within 12 inches (31 cm) from the bottom of the enclosure. The openings must communicate directly, or by ducts, with the outdoors or spaces (crawl or attic) that freely communicate with the outdoors.

  1. When directly communicating with the outdoors, each opening must have a minimum free area of 1 inch² (6.5 cm²) per 4000 BTU (1.2 kw) per hour of total input rating of all equipment in the enclosure.
  2. When communicating with the outdoors through vertical ducts, each opening must have a minimum free area of 1 inch² (6.5 cm²) per 4000 BTU (1.2 kw) per hour of total input rating of all equipment in the enclosure.
  3. When communicating with the outdoors through the horizontal ducts , each opening must have a minimum free area of 1 inch² (6.5 cm²)  per 2000 BTU (0.6 kw) per hour of total input rating of all equipment in the enclosure.
  4. When ducts are used, they must be of the same cross-sectional area as the free area of the openings to which the connect. The minimum dimensions of rectangular air ducts must be not less than 3 inches (7.5cm)

Specially Engineered Installations

The requirements noted under the CONFINED SPACES above must not necessarily govern when special engineering, approved by the authority having jurisdiction, provides an adequate supply of air for combustion, ventilation, and dilution of flue gases.

Sequence of Operation

The sequence of operation is important to know so you can properly diagnose the problem.

Control Sequence of Operation

Start up sequence

Upon powering up, the control checks for the presence of the resistive plug, if the resistance is in the expected range the control will begin normal operation after 5 to 8 seconds.

Normal Heating Sequence

  1. The thermostat senses a need for heat.
  2. The control checks the pressure switch condition.
  3. If the pressure switch is open, the control sends power to the blower motor.
  4. The blower starts moving combustion air through the combustion system.
  5. The pressure switches closes.
  6. The control senses the closed pressure switch and starts the ignition process by providing a spark at the pilot electrode and allowing gas to flow to the pilot.
  7. When the pilot is lit the gas control senses the pilot flame and opens the main gas valve.
  8. The main burner is lit.
  9. The main burner and blower continue to operate until the thermostat is satisfied.
  10. When the thermostat is satisfied the main and pilot gas valves close.
  11. The blower operates for a short post purge period before shutting down.
  12. The water heater remains in the stand-by mode until the next call for heat.
  13. Make sure Power Vent is plugged into a grounded outlet.
  14. Make sure you have correct continuinty

Maintenance

  1. Annually check the operation of the thermostat
  2. The flow of combustion and ventilation air MUST NOT be restricted. Clear the combustion air openings of any dirt, dust, or other restrictions. WARNING! The ventilation air system may be HOT.
  3. At all times keep the water heater area clear and free from combustible materials, gasoline and other flammable vapors and liquids.
  4. Bi-annually conduct a visual check of the main and pilot burner flames to determine that they are burning properly. see Burner Flame Check. If sooting or other burner anomalies are evident, shut down the water heater by turning off the gas per the instructions listed in this manual or as listed on the water heater.
  5. Annually remove the inner door and main burner assembly to clean orifices and related parts of any dirt or other foreign material. Inspect the burner ports for obstructions or debris and clean with a wire brush as needed. Wire brush and/or vacuum clean the combustion chamber as needed to remove scale deposits and debris. NOTE: It is imperative for proper operation of the water that the inner door replaced in the original location.
  6. At least once a year, check the combination temperature and pressure relief valve to insure that the valve has not become encrusted with lime. Lift the lever at the top of the valve several times until the valve seats properly without leaking.
  7. Monthly drain off a gallon of water to remove silt and sediment.
  8. If the combination temperature and pressure relief valve on the appliance discharges periodically, this may be due to thermal expansion in a closed water supply system. Contact the Ace Hi Plumbing, Heating and Air to help correct this problem. Do not plug the combination temperature and pressure relief valve outlet.
  9. A combination sacrificial anode rod/hot water outlet nipple has been installed to extend tank life. The anode rod should be inspected annual and replaced when necessary to prolong tank life. Water conditions in your area will influence the time interval for inspection and replacement of the anode rod. The use of a water softener may increase the speed of anode consumption. More frequent inspection of the anode is needed when using softened (or phosphate treated) water.
  10. The blower has sealed motor bearings and does not require adding oil.

Short Cycling Boilers

Boiler Short Cycling is when the boiler overheats and shuts off before reaching peak efficiency. If your boiler just recently started short cycling, there can be many different factors causing this issue.

Thermostat

If your thermostat is out of calibration your burner will be bouncing on and off. If your thermostat has a mercury switch first make sure the thermostat hangs level on the wall. Also look to see if the thermostat is in a cold draft area or possibly hanging on a poorly insulated wall. These could all be contributing factors to your thermostat getting incorrect readings. Then causing your boiler to fire inconsistently.

Air Vents

Air vents are crucial to your system running correctly. If your vents are clogged air will become trapped in your system and it will pressurize causing an air bubble which water wont pass through. Your boiler wont be cycling the water at this point and will overheat quickly causing it to shutoff before being able to distribute hot water throughout the house. Often this will be caught in a boiler maintenance and fixed before causing any issues.

Over sized Boilers

If your boiler is over sized it will satisfy the space heating demands too quickly , then shut down until heat is required again. This is bad because the longer your boiler runs the more efficient it will be. This can often happen when you have multiple zones in a home but only one of them is calling for heat. Therefore the amount of water flowing through the boiler is a fraction of what was expected. When you have an on-off boiler (no modulation) this becomes more prevalent and the more the boiler is over-sized, the more often it will occur. A modulating boiler does good in this circumstance because it will adjust the flame according to the load, rather then just shutting down on high limit from lack of flow.

Circulating Pumps

Circulating pumps are used to force hot water from the boiler through the radiating devices such as hot water baseboards or radiators. The circulators are switched on as needed or in some cases they will be designed to run continuously. If your pump stops working it will no longer be able to circulate the water in the zone causing your boiler to overheat and begin short cycling.

Boiler Dry Cycling

When the boiler currently at the temperature set point and is in stand by mode as no further heat is required from the system load (no zones calling for heat). Due to the ambient radiated heat loses, together with the flue drought heat losses (standing losses) The boiler will naturally cool down over time which may cause the temperature controls to instruct the boiler to re fire and return the boiler back to the set point temperature. In this case the heat is not being used by the heating system it is only replacing the “standing heat loss” and therefore wasting energy.

Boiler short cycling is unhealthy overall for your system. If you have any boiler issues in Northern Colorado, call Ace Hi Plumbing, Heating and Air Conditioning, Today and schedule an appointment with one of our heating specialists.

 

The Advantages of Installing a Boiler for Your Heating

Boilers were among the first of whole home heating systems, so they’ve been around a long time – but don’t let that imply they are not up to date with today’s standard for energy efficiency. Today’s boilers have average efficiency ratings of 89%, in addition to providing other benefits for your home heating. But quality installation is just as important as having good equipment, so if you are ready to install a boiler in Northern Colorado, make sure you call the people you can trust: Ace Hi Plumbing, Heating and Air.

Two Types of Boilers

Boilers are part of a hydronic system, meaning they use hot water or steam to heat your home. There are two ways in which the water can be heated

  • Water Tube
  • Fire Tube

With a water tube boiler, the water is held inside metal tubes that are heated on the outside via flames or hot gases. In a fire tube boiler, the opposite occurs : tubes are placed inside the water container; the tubes are then heated with combustion gases. and the heat from the tubes transfers into the water. The two most common fuels used are gas and oil, but other fuels like wood or wood pellets can also be used.

Advantages of Boiler Systems Comparative to Furnaces

Boiler systems have a few advantages that make them attractive to homeowners:

  • Good for allergy sufferers – hydronic systems do not rely on forced air distribution, instead utilizing radiant heating systems or radiators. As such, there is no circulating dust to worry about, which can be very beneficial should you have allergy sufferers in your home.
  • Even gradual heating – the heating of a boiler system is very gradual, as outlet points radiate the heat as opposed to blowing it out, as with a forced-air system.
  • Easy zoning – the piping used with a boiler system can be easily zoned then duct-work. Also allows for more comfort from room to room with designated zones.
  • Quiet operation – the only time you hear noise is when your boiler is heating the water in your system, otherwise, the operation is very quiet.
  • Retains heat longer for better over all efficiency. With a furnace, if you open your door you lose a lot of your heat and have to recover that gradually. With a boiler your heat stays retained within the pipes keeping your floors warmer with significantly less heat loss.

Hydronic heating is a safe, comfortable and economical way to heat your home. Hydronic systems circulate hot water through baseboards, radiators and or radiant tubing in your floors or ceilings. There are many advantages to heating your home using a hydronic system, whether it is a new install or retrofit for your existing system.

The Importance of Boiler Maintenance

One of the most significant reasons why good boiler maintenance is so important is because it helps prevent unexpected shutdowns which could not only be inconvenient but also costly for after hours calls. Getting set up on a scheduled boiler maintenance and inspection helps increase the life of your boiler and takes all the worry out of the last minute service calls.

This scheduled maintenance is especially important to check for leaks on your flues and heat exchanger. If your flue or heat exchanger is damaged from lack of maintenance you are putting you and your family at risk of Co2 exposure. Your boiler technician will check for Co2 levels to make sure your family is safe against this silent killer. This also goes for a heat exchanger on your furnace.

Side Arm Tanks

Side arms tanks are used so that the boiler can provide both space heating and domestic hot water (DHW). The tank stores a consistent temperature water similar to a hot water tank so when there is a call for heat in the home your hot water use will not be compromised. These can really make a huge difference in your home comfort if you already have a boiler without a sidearm that also provides DHW for your home. The thermal mass of the side arm tank stabilizes domestic hot water delivery temperature during long demand periods. This help reduce fluctuation in delivery temperature throughout your daily use.

 

 

Boilers have been around a long time for good reasons. If you think a boiler system in Loveland is a good fit for you, call Ace Hi Heating and Air Conditioning, Today and schedule an appointment with one of our installation specialists.