I have a hydronic heat pump going in High Pressure lockout. The dealer told me to close 50% the in and out valves on the ground side. Doing so the pump is running, but I think is not the solution. In the manufacturer manual for HP lockout are 2 possbility: overcharged with refrigerant, or malfunction of Expansion valve and sensing bulb. Could someone help me in solving the problem?
90% Most of the high pressure issues we come across are flow issues: - short loop - low flow (air, small pump) on either source or load side
For sure is not a low flow problem. The pump was installed 2 years ago, and it worked properly till 2 month ago. If it was a problem of low flow, why is running only with the valves on the ground side closed 50%, that means only in low flow conditions?
It would be prudent to check entering and leaving temperatures on both the load and source side lines at the unit.
is this a water to water unit? we definately need to look at low side entering and leaving temps. are you saying that you are throttling flow to the ground loops? Joe
Friday, October 29, 2010 Yes it is a water to water unit. The Pump model is ECONAR Hydronic GEOSOURCE 2000 GW 670 23.9KW. It works only if the groung loop flow is throttling. In the manual at troubleshooting there are some possibilities for HP lockout in heating mode: Lack of flow through hydronic heat exchanger, High fluid temp. in the hydronic loop, Overcharged refrigerant circuit, Expansion valve / sensing bulb malfunction. Where to start searching?
In heating mode high source loop temps can cause HP lockout. Could be why throttling the flow helps keep things running. Before you start tearing into things I would get those temps first. Might save you a lot time and money.
Do you cool with this system as well? How old is the system. If it works in the fashion your installer suggests it should, why are you concerned? j
