Argo 20KW electric boiler

Grant_2

I installed a new argo boiler and the electrical/control work was completed last Tuesday (Dec4). There is a total of about 40 feet of 1" copper pipe in the system. It is a hydro air system, with 2 zones (upstairs and downstairs)--each with their own tstats.

When a tstat calls for heat, the fan comes on, then the circ pump, then the elements themselves. The boiler specs indicate that the elements (4) will energize one at a time at 30 second intervals to bring the boiler to set point (160 degrees). If the heat demand is not satisfied, the boiler will energize only the # of elements required to maintain setpoint temp.

Here's what actually happens:
1. pump comes on and the 1st element comes on shortly after (30sec). The second and 3rd element come on at approx. 1.5 minute intervals. The 4th element will come on at approx. 14 minutes. Usually the tstat is satisfied before the boiler comes up to 160 degrees--at approx. 23 min. Elements shut off and the pump runs for approx 3 minutes before shutdown.

2. While testing the system, I turned the 2nd. tsat up about 5 minutes after the first one had been satisfied. The blower came on immediately. As the boiler temp drops, the 1st. element comes on - and that's it! Soon the boiler temp is <100 degrees and still only the 1st. element is on.

YESTERDAY, a new control board was installed. The scenario in #1 above is still the same. Scenario #2 now happens according to specs--element 1 comes on at differential point (-12 degrees), and the other elements energize at 30 second intervals - as required by demand. The tsat is still satisfied before the boiler reaches setpoint (160).

I will be getting the control guy back to put a timer relay on the fan so that the boiler has a chance to get up to temp before the fan kicks in.

What I need help with is scenario #1. I would like the boiler to energize the elements at 30 second intervals as the literature states it does. Most starts are from approx. 65 degrees, as the system is intended to be a back up for the wood heater which heats the main floor--hence the boiler system will only be used when I'm away or when the wood heater can't keep up.

Sorry to be so long winded!!! Any help would be appreciated.