Explanation of an installation correction

Here is an explanation of a recent correction of an existing installation. The owner called us because the system was showing a fault and the heat was poor in both the owners and tenant units. 

There were two Viessmann 100W boilers installed. One for landlord and one for the tenant. The tenant's boiler was over sized. The landlord's boiler had 5 zones and was short cycling because the boiler was over sized for each zone. We removed the zones and piped the system for continuous flow and modulation of the temperature. 

Distribution piping was done with Pex. Pex should not be used in distribution system. While we couldn't change the pex that was inside the walls, we removed the pex in the basement and used rigid copper piping.

The original Plumber did not filed paperwork with DOB and did not pass plumbing inspection. 

Exhaust and fresh air intake piping was undersized and exceed maximum allowed length. Exhaust piping had reversed pitch, leading to condensate accumulation and further restriction of exhaust. Because of these conditions boilers were de-rated and could not output necessary heat to heat the house. We fixed the reversed pitch to remove the condensate accumulation. 

Outdoor sensor was not installed and boiler did not operate with outdoor reset as it was intended to work. We installed outdoor reset and set the system to work as intended. One boiler now services the entire house while the second boiler is used for peak load on very cold days. 

Condensing boilers produce acidic condensate during operation and this condensate must be neutralized. In this installation the acid neutralizer was missing. This is not only bad for the piping, it is also a code violation. Acid neutralizer was installed. 

Indirect fired domestic hot water heaters were installed without mixing valve. Which can lead to uncontrolled and excessive domestic hot water temperature. Also it is code violation. The domestic hot water was repiped to use only one tank for the whole house with a mixing valve and domestic hot water priority. 

Domestic hot water circulator was not installed. Water in hot water pipes cooled down when not used and cold water is discharged from hot water faucets before hot water comes out. A lot of water and time is wasted. Circulator eliminates this problem. This was installed. We installed a smart recirculating pump that remembers the usage and ensures that hot water is ready for use when needed. 

Distribution and near boiler piping was not insulated. We insulated the new rigid pipe. 

There was no hydrolic separation between boiler and heating loops. We installed the system properly with all necessary loops.

No water treatment had been done. We did a system cleaning to remove rust from the system and introduced a rust inhibitor.